497

December 6, 2017

Via EDGAR Electronic Transmission

Division of Investment Management

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Re: Pacific Funds Series Trust

(File Nos. 333-61366 and 811-10385)

Dear Sir or Madam:

On behalf of Pacific Funds Series Trust, transmitted herewith for filing pursuant to Rule 497 under the Securities Act of 1933, as amended (“Rule 497”), is the exhibit in the eXtensible Business Reporting Language (“XBRL”) format that reflects the risk/return summary information included in the prospectus supplement filed pursuant to Rule 497 on November 28, 2017 (accession number 0001193125-17-352709) to the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class Prospectus dated August 1, 2017, as supplemented. The supplements are incorporated by reference into this Rule 497 document.

If you have any questions or comments, please contact the undersigned at (949) 219-3224 or by e-mail at Mark.Karpe@PacificLife.com.

Sincerely,

/s/ Mark Karpe

Mark Karpe

Assistant Vice President and Counsel

cc: Laurene E. MacElwee, Pacific Life Fund Advisors LLC

Robin S. Yonis, Esq., Pacific Life Fund Advisors LLC

Audrey L. Cheng, Esq., Pacific Life Insurance Company

Anthony H. Zacharski, Esq., Dechert LLP

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Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Document Type	dei_DocumentType	497
Document Period End Date	dei_DocumentPeriodEndDate	Mar. 31, 2017
Registrant Name	dei_EntityRegistrantName	PACIFIC FUNDS SERIES TRUST
Central Index Key	dei_EntityCentralIndexKey	0001137761
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Nov. 28, 2017
Document Effective Date	dei_DocumentEffectiveDate	Nov. 28, 2017
Prospectus Date	rr_ProspectusDate	Aug. 01, 2017

XML

Aug. 01, 2017

SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Conservative		Pacific Funds Portfolio Optimization Moderate- Conservative		Pacific Funds Portfolio Optimization Moderate		Pacific Funds Portfolio Optimization Growth		Pacific Funds Portfolio Optimization Aggressive- Growth
Class A (before)		1.27%		1.31%		1.36%		1.41%		1.44%
Class A (after)		1.24%		1.24%		1.26%		1.28%		1.31%
Class A decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Class B (before)		2.02%		2.06%		2.11%		2.16%		2.19%
Class B (after)		1.99%		1.99%		2.01%		2.03%		2.06%
Class B decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Class C (before)		2.02%		2.06%		2.11%		2.16%		2.19%
Class C (after)		1.99%		1.99%		2.01%		2.03%		2.06%
Class C decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Class R (before)		1.52%		1.56%		1.61%		1.66%		1.69%
Class R (after)		1.49%		1.49%		1.51%		1.53%		1.56%
Class R decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Advisor Class (before)		1.02%		1.06%		1.11%		1.16%		1.19%
Advisor Class (after)		0.99%		0.99%		1.01%		1.03%		1.06%
Advisor Class decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Conservative

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.23%		0.23%		0.23%		0.23%		0.23%
Acquired Fund Fees and Expenses1		0.64%		0.64%		0.64%		0.64%		0.64%
Total Annual Fund Operating Expenses		1.32%		2.07%		2.07%		1.57%		1.07%
Less Expense Reimbursement2		(0.08%)		(0.08%)		(0.08%)		(0.08%)		(0.08%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.24%		1.99%		1.99%		1.49%		0.99%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	702	$	302	$	152	$	101
3 years	$	938	$	1,041	$	641	$	488	$	332
5 years	$	1,226	$	1,306	$	1,106	$	848	$	582
10 years	$	2,046	$	2,202	$	2,394	$	1,861	$	1,298

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	202	$	202	$	152	$	101
3 years	$	938	$	641	$	641	$	488	$	332
5 years	$	1,226	$	1,106	$	1,106	$	848	$	582
10 years	$	2,046	$	2,202	$	2,394	$	1,861	$	1,298

Pacific Funds Portfolio Optimization Moderate-Conservative

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.22%		0.22%		0.22%		0.22%		0.22%
Acquired Fund Fees and Expenses1		0.64%		0.64%		0.64%		0.64%		0.64%
Total Annual Fund Operating Expenses		1.31%		2.06%		2.06%		1.56%		1.06%
Less Expense Reimbursement2		(0.07%)		(0.07%)		(0.07%)		(0.07%)		(0.07%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.24%		1.99%		1.99%		1.49%		0.99%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	702	$	302	$	152	$	101
3 years	$	936	$	1,039	$	639	$	486	$	330
5 years	$	1,222	$	1,302	$	1,102	$	843	$	578
10 years	$	2,036	$	2,192	$	2,384	$	1,851	$	1,288

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	202	$	202	$	152	$	101
3 years	$	936	$	639	$	639	$	486	$	330
5 years	$	1,222	$	1,102	$	1,102	$	843	$	578
10 years	$	2,036	$	2,192	$	2,384	$	1,851	$	1,288

Pacific Funds Portfolio Optimization Moderate

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.21%		0.21%		0.21%		0.21%		0.21%
Acquired Fund Fees and Expenses1		0.66%		0.66%		0.66%		0.66%		0.66%
Total Annual Fund Operating Expenses		1.32%		2.07%		2.07%		1.57%		1.07%
Less Expense Reimbursement2		(0.06%)		(0.06%)		(0.06%)		(0.06%)		(0.06%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.26%		2.01%		2.01%		1.51%		1.01%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	671	$	704	$	304	$	154	$	103
3 years	$	940	$	1,043	$	643	$	490	$	334
5 years	$	1,228	$	1,308	$	1,108	$	849	$	584
10 years	$	2,048	$	2,203	$	2,395	$	1,862	$	1,300

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	671	$	204	$	204	$	154	$	103
3 years	$	940	$	643	$	643	$	490	$	334
5 years	$	1,228	$	1,108	$	1,108	$	849	$	584
10 years	$	2,048	$	2,203	$	2,395	$	1,862	$	1,300

Pacific Funds Portfolio Optimization Growth

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.22%		0.22%		0.22%		0.22%		0.22%
Acquired Fund Fees and Expenses1		0.68%		0.68%		0.68%		0.68%		0.68%
Total Annual Fund Operating Expenses		1.35%		2.10%		2.10%		1.60%		1.10%
Less Expense Reimbursement2		(0.07%)		(0.07%)		(0.07%)		(0.07%)		(0.07%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.28%		2.03%		2.03%		1.53%		1.03%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	673	$	706	$	306	$	156	$	105
3 years	$	948	$	1,051	$	651	$	498	$	343
5 years	$	1,242	$	1,322	$	1,122	$	864	$	599
10 years	$	2,079	$	2,234	$	2,426	$	1,894	$	1,334

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	673	$	206	$	206	$	156	$	105
3 years	$	948	$	651	$	651	$	498	$	343
5 years	$	1,242	$	1,122	$	1,122	$	864	$	599
10 years	$	2,079	$	2,234	$	2,426	$	1,894	$	1,334

Pacific Funds Portfolio Optimization Aggressive-Growth

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.23%		0.23%		0.23%		0.23%		0.23%
Acquired Fund Fees and Expenses1		0.71%		0.71%		0.71%		0.71%		0.71%
Total Annual Fund Operating Expenses		1.39%		2.14%		2.14%		1.64%		1.14%
Less Expense Reimbursement2		(0.08%)		(0.08%)		(0.08%)		(0.08%)		(0.08%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.31%		2.06%		2.06%		1.56%		1.06%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	676	$	709	$	309	$	159	$	108
3 years	$	958	$	1,062	$	662	$	509	$	354
5 years	$	1,261	$	1,342	$	1,142	$	884	$	620
10 years	$	2,120	$	2,275	$	2,466	$	1,937	$	1,379

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	676	$	209	$	209	$	159	$	108
3 years	$	958	$	662	$	662	$	509	$	354
5 years	$	1,261	$	1,142	$	1,142	$	884	$	620
10 years	$	2,120	$	2,275	$	2,466	$	1,937	$	1,379

Pacific Funds Portfolio Optimization Conservative – Sector Risk is deleted from and the following risk is added to the Principal Risks from Holdings in Underlying Funds subsection:

• Growth Companies Risk: The PF Multi-Asset Fund’s use of derivatives to gain exposure to the growth investment style subjects it to this risk. Growth companies have the potential for above-average or rapid growth but may be subject to greater price volatility risk than investments in “undervalued” companies.

Pacific Funds Portfolio Optimization Moderate-Conservative – Sector Risk is deleted from the Principal Risks from Holdings in Underlying Funds subsection.

Pacific Funds Portfolio Optimization Aggressive-Growth – Forward Commitments Risk is deleted from and the following risks are added to the Principal Risks from Holdings in Underlying Funds subsection:

• Credit Risk: An issuer or guarantor of a debt instrument might be unable or unwilling to meet its financial obligations and might not make interest or principal payments on an instrument when those payments are due (“default”). Defaults may potentially reduce an Underlying Fund’s income or ability to recover amounts due and may reduce the value of the debt instrument, sometimes dramatically.

• Debt Securities Risk: Debt securities and other debt instruments are subject to many risks, including interest rate risk, market and regulatory risk, credit risk, price volatility risk, and liquidity risk, which may affect their value.

• Interest Rate Risk: The value of fixed income investments may fall when interest rates rise. Debt instruments with longer durations tend to be more sensitive to changes in interest rates, making them more volatile than debt instruments with shorter durations or floating or adjustable interest rates.

• Mortgage-Related and Other Asset-Backed Securities Risk: Mortgage-related and other asset-backed securities are subject to certain risks. The value of these securities will be influenced by the factors affecting the housing market or the market for the assets underlying such securities. As a result, during periods of declining asset value, difficult or frozen credit markets, swings in interest rates, or deteriorating economic conditions, these securities may decline in value, become difficult to value, become more volatile and/or become illiquid. These securities are also subject to extension risk, where borrowers or issuers may pay principal later than expected, causing these securities to lengthen in duration and be more volatile in rising interest rate conditions. These securities are also subject to prepayment and call risk, where borrowers or issuers, respectively, may pay principal sooner than expected, causing proceeds to be reinvested at lower prevailing interest rates.

• Swap Agreements Risk: Swap agreements are derivative contracts where the parties agree to exchange the returns earned on specific assets, such as the return on, or increase in value of, an amount invested in a particular foreign currency, or in a “basket” of securities representing a certain index, or at a specific interest rate. As a derivative, it is subject to derivatives risk, including counterparty risk.

• U.S. Government Securities Risk: Not all U.S. government securities are backed or guaranteed by the U.S. government and different U.S. government securities are subject to varying degrees of credit risk. There is risk that the U.S. government will not make timely payments on its debt or provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if those entities are not able to meet their financial obligations.

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PACIFIC FUNDS SERIES TRUST

Prospectus Date

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Aug. 01, 2017

Supplement [Text Block]

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SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Conservative		Pacific Funds Portfolio Optimization Moderate- Conservative		Pacific Funds Portfolio Optimization Moderate		Pacific Funds Portfolio Optimization Growth		Pacific Funds Portfolio Optimization Aggressive- Growth
Class A (before)		1.27%		1.31%		1.36%		1.41%		1.44%
Class A (after)		1.24%		1.24%		1.26%		1.28%		1.31%
Class A decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Class B (before)		2.02%		2.06%		2.11%		2.16%		2.19%
Class B (after)		1.99%		1.99%		2.01%		2.03%		2.06%
Class B decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Class C (before)		2.02%		2.06%		2.11%		2.16%		2.19%
Class C (after)		1.99%		1.99%		2.01%		2.03%		2.06%
Class C decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Class R (before)		1.52%		1.56%		1.61%		1.66%		1.69%
Class R (after)		1.49%		1.49%		1.51%		1.53%		1.56%
Class R decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)
Advisor Class (before)		1.02%		1.06%		1.11%		1.16%		1.19%
Advisor Class (after)		0.99%		0.99%		1.01%		1.03%		1.06%
Advisor Class decrease		(0.03%)		(0.07%)		(0.10%)		(0.13%)		(0.13%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Conservative

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.23%		0.23%		0.23%		0.23%		0.23%
Acquired Fund Fees and Expenses1		0.64%		0.64%		0.64%		0.64%		0.64%
Total Annual Fund Operating Expenses		1.32%		2.07%		2.07%		1.57%		1.07%
Less Expense Reimbursement2		(0.08%)		(0.08%)		(0.08%)		(0.08%)		(0.08%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.24%		1.99%		1.99%		1.49%		0.99%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	702	$	302	$	152	$	101
3 years	$	938	$	1,041	$	641	$	488	$	332
5 years	$	1,226	$	1,306	$	1,106	$	848	$	582
10 years	$	2,046	$	2,202	$	2,394	$	1,861	$	1,298

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	202	$	202	$	152	$	101
3 years	$	938	$	641	$	641	$	488	$	332
5 years	$	1,226	$	1,106	$	1,106	$	848	$	582
10 years	$	2,046	$	2,202	$	2,394	$	1,861	$	1,298

Pacific Funds Portfolio Optimization Moderate-Conservative

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.22%		0.22%		0.22%		0.22%		0.22%
Acquired Fund Fees and Expenses1		0.64%		0.64%		0.64%		0.64%		0.64%
Total Annual Fund Operating Expenses		1.31%		2.06%		2.06%		1.56%		1.06%
Less Expense Reimbursement2		(0.07%)		(0.07%)		(0.07%)		(0.07%)		(0.07%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.24%		1.99%		1.99%		1.49%		0.99%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	702	$	302	$	152	$	101
3 years	$	936	$	1,039	$	639	$	486	$	330
5 years	$	1,222	$	1,302	$	1,102	$	843	$	578
10 years	$	2,036	$	2,192	$	2,384	$	1,851	$	1,288

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	202	$	202	$	152	$	101
3 years	$	936	$	639	$	639	$	486	$	330
5 years	$	1,222	$	1,102	$	1,102	$	843	$	578
10 years	$	2,036	$	2,192	$	2,384	$	1,851	$	1,288

Pacific Funds Portfolio Optimization Moderate

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.21%		0.21%		0.21%		0.21%		0.21%
Acquired Fund Fees and Expenses1		0.66%		0.66%		0.66%		0.66%		0.66%
Total Annual Fund Operating Expenses		1.32%		2.07%		2.07%		1.57%		1.07%
Less Expense Reimbursement2		(0.06%)		(0.06%)		(0.06%)		(0.06%)		(0.06%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.26%		2.01%		2.01%		1.51%		1.01%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	671	$	704	$	304	$	154	$	103
3 years	$	940	$	1,043	$	643	$	490	$	334
5 years	$	1,228	$	1,308	$	1,108	$	849	$	584
10 years	$	2,048	$	2,203	$	2,395	$	1,862	$	1,300

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	671	$	204	$	204	$	154	$	103
3 years	$	940	$	643	$	643	$	490	$	334
5 years	$	1,228	$	1,108	$	1,108	$	849	$	584
10 years	$	2,048	$	2,203	$	2,395	$	1,862	$	1,300

Pacific Funds Portfolio Optimization Growth

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.22%		0.22%		0.22%		0.22%		0.22%
Acquired Fund Fees and Expenses1		0.68%		0.68%		0.68%		0.68%		0.68%
Total Annual Fund Operating Expenses		1.35%		2.10%		2.10%		1.60%		1.10%
Less Expense Reimbursement2		(0.07%)		(0.07%)		(0.07%)		(0.07%)		(0.07%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.28%		2.03%		2.03%		1.53%		1.03%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	673	$	706	$	306	$	156	$	105
3 years	$	948	$	1,051	$	651	$	498	$	343
5 years	$	1,242	$	1,322	$	1,122	$	864	$	599
10 years	$	2,079	$	2,234	$	2,426	$	1,894	$	1,334

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	673	$	206	$	206	$	156	$	105
3 years	$	948	$	651	$	651	$	498	$	343
5 years	$	1,242	$	1,122	$	1,122	$	864	$	599
10 years	$	2,079	$	2,234	$	2,426	$	1,894	$	1,334

Pacific Funds Portfolio Optimization Aggressive-Growth

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.23%		0.23%		0.23%		0.23%		0.23%
Acquired Fund Fees and Expenses1		0.71%		0.71%		0.71%		0.71%		0.71%
Total Annual Fund Operating Expenses		1.39%		2.14%		2.14%		1.64%		1.14%
Less Expense Reimbursement2		(0.08%)		(0.08%)		(0.08%)		(0.08%)		(0.08%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.31%		2.06%		2.06%		1.56%		1.06%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	676	$	709	$	309	$	159	$	108
3 years	$	958	$	1,062	$	662	$	509	$	354
5 years	$	1,261	$	1,342	$	1,142	$	884	$	620
10 years	$	2,120	$	2,275	$	2,466	$	1,937	$	1,379

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	676	$	209	$	209	$	159	$	108
3 years	$	958	$	662	$	662	$	509	$	354
5 years	$	1,261	$	1,142	$	1,142	$	884	$	620
10 years	$	2,120	$	2,275	$	2,466	$	1,937	$	1,379

Pacific Funds Portfolio Optimization Conservative – Sector Risk is deleted from and the following risk is added to the Principal Risks from Holdings in Underlying Funds subsection:

• Growth Companies Risk: The PF Multi-Asset Fund’s use of derivatives to gain exposure to the growth investment style subjects it to this risk. Growth companies have the potential for above-average or rapid growth but may be subject to greater price volatility risk than investments in “undervalued” companies.

Pacific Funds Portfolio Optimization Moderate-Conservative – Sector Risk is deleted from the Principal Risks from Holdings in Underlying Funds subsection.

Pacific Funds Portfolio Optimization Aggressive-Growth – Forward Commitments Risk is deleted from and the following risks are added to the Principal Risks from Holdings in Underlying Funds subsection:

• Credit Risk: An issuer or guarantor of a debt instrument might be unable or unwilling to meet its financial obligations and might not make interest or principal payments on an instrument when those payments are due (“default”). Defaults may potentially reduce an Underlying Fund’s income or ability to recover amounts due and may reduce the value of the debt instrument, sometimes dramatically.

• Debt Securities Risk: Debt securities and other debt instruments are subject to many risks, including interest rate risk, market and regulatory risk, credit risk, price volatility risk, and liquidity risk, which may affect their value.

• Interest Rate Risk: The value of fixed income investments may fall when interest rates rise. Debt instruments with longer durations tend to be more sensitive to changes in interest rates, making them more volatile than debt instruments with shorter durations or floating or adjustable interest rates.

• Mortgage-Related and Other Asset-Backed Securities Risk: Mortgage-related and other asset-backed securities are subject to certain risks. The value of these securities will be influenced by the factors affecting the housing market or the market for the assets underlying such securities. As a result, during periods of declining asset value, difficult or frozen credit markets, swings in interest rates, or deteriorating economic conditions, these securities may decline in value, become difficult to value, become more volatile and/or become illiquid. These securities are also subject to extension risk, where borrowers or issuers may pay principal later than expected, causing these securities to lengthen in duration and be more volatile in rising interest rate conditions. These securities are also subject to prepayment and call risk, where borrowers or issuers, respectively, may pay principal sooner than expected, causing proceeds to be reinvested at lower prevailing interest rates.

• Swap Agreements Risk: Swap agreements are derivative contracts where the parties agree to exchange the returns earned on specific assets, such as the return on, or increase in value of, an amount invested in a particular foreign currency, or in a “basket” of securities representing a certain index, or at a specific interest rate. As a derivative, it is subject to derivatives risk, including counterparty risk.

• U.S. Government Securities Risk: Not all U.S. government securities are backed or guaranteed by the U.S. government and different U.S. government securities are subject to varying degrees of credit risk. There is risk that the U.S. government will not make timely payments on its debt or provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if those entities are not able to meet their financial obligations.

Pacific Funds Portfolio Optimization Conservative

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

plf_SupplementTextBlock

SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Conservative
Class A (before)		1.27%
Class A (after)		1.24%
Class A decrease		(0.03%)
Class B (before)		2.02%
Class B (after)		1.99%
Class B decrease		(0.03%)
Class C (before)		2.02%
Class C (after)		1.99%
Class C decrease		(0.03%)
Class R (before)		1.52%
Class R (after)		1.49%
Class R decrease		(0.03%)
Advisor Class (before)		1.02%
Advisor Class (after)		0.99%
Advisor Class decrease		(0.03%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Conservative

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.23%		0.23%		0.23%		0.23%		0.23%
Acquired Fund Fees and Expenses1		0.64%		0.64%		0.64%		0.64%		0.64%
Total Annual Fund Operating Expenses		1.32%		2.07%		2.07%		1.57%		1.07%
Less Expense Reimbursement2		(0.08%)		(0.08%)		(0.08%)		(0.08%)		(0.08%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.24%		1.99%		1.99%		1.49%		0.99%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	702	$	302	$	152	$	101
3 years	$	938	$	1,041	$	641	$	488	$	332
5 years	$	1,226	$	1,306	$	1,106	$	848	$	582
10 years	$	2,046	$	2,202	$	2,394	$	1,861	$	1,298

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	202	$	202	$	152	$	101
3 years	$	938	$	641	$	641	$	488	$	332
5 years	$	1,226	$	1,106	$	1,106	$	848	$	582
10 years	$	2,046	$	2,202	$	2,394	$	1,861	$	1,298

Pacific Funds Portfolio Optimization Conservative – Sector Risk is deleted from and the following risk is added to the Principal Risks from Holdings in Underlying Funds subsection:

• Growth Companies Risk: The PF Multi-Asset Fund’s use of derivatives to gain exposure to the growth investment style subjects it to this risk. Growth companies have the potential for above-average or rapid growth but may be subject to greater price volatility risk than investments in “undervalued” companies.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Your expenses (in dollars) if you SELL your shares at the end of each period.

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.

Pacific Funds Portfolio Optimization Conservative | Class A

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.32%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[2]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.24%

1 year

rr_ExpenseExampleYear01

$ 669

3 years

rr_ExpenseExampleYear03

938

5 years

rr_ExpenseExampleYear05

1,226

10 years

rr_ExpenseExampleYear10

2,046

1 year

rr_ExpenseExampleNoRedemptionYear01

669

3 years

rr_ExpenseExampleNoRedemptionYear03

938

5 years

rr_ExpenseExampleNoRedemptionYear05

1,226

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,046

Pacific Funds Portfolio Optimization Conservative | Class B

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.07%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[2]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.99%

1 year

rr_ExpenseExampleYear01

$ 702

3 years

rr_ExpenseExampleYear03

1,041

5 years

rr_ExpenseExampleYear05

1,306

10 years

rr_ExpenseExampleYear10

2,202

1 year

rr_ExpenseExampleNoRedemptionYear01

202

3 years

rr_ExpenseExampleNoRedemptionYear03

641

5 years

rr_ExpenseExampleNoRedemptionYear05

1,106

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,202

Pacific Funds Portfolio Optimization Conservative | Class C

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.07%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[2]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.99%

1 year

rr_ExpenseExampleYear01

$ 302

3 years

rr_ExpenseExampleYear03

641

5 years

rr_ExpenseExampleYear05

1,106

10 years

rr_ExpenseExampleYear10

2,394

1 year

rr_ExpenseExampleNoRedemptionYear01

202

3 years

rr_ExpenseExampleNoRedemptionYear03

641

5 years

rr_ExpenseExampleNoRedemptionYear05

1,106

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,394

Pacific Funds Portfolio Optimization Conservative | Class R

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.57%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[2]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.49%

1 year

rr_ExpenseExampleYear01

$ 152

3 years

rr_ExpenseExampleYear03

488

5 years

rr_ExpenseExampleYear05

848

10 years

rr_ExpenseExampleYear10

1,861

1 year

rr_ExpenseExampleNoRedemptionYear01

152

3 years

rr_ExpenseExampleNoRedemptionYear03

488

5 years

rr_ExpenseExampleNoRedemptionYear05

848

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,861

Pacific Funds Portfolio Optimization Conservative | Advisor Class

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.07%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[2]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

0.99%

1 year

rr_ExpenseExampleYear01

$ 101

3 years

rr_ExpenseExampleYear03

332

5 years

rr_ExpenseExampleYear05

582

10 years

rr_ExpenseExampleYear10

1,298

1 year

rr_ExpenseExampleNoRedemptionYear01

101

3 years

rr_ExpenseExampleNoRedemptionYear03

332

5 years

rr_ExpenseExampleNoRedemptionYear05

582

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,298

Pacific Funds Portfolio Optimization Moderate-Conservative

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

plf_SupplementTextBlock

SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Moderate- Conservative
Class A (before)		1.31%
Class A (after)		1.24%
Class A decrease		(0.07%)
Class B (before)		2.06%
Class B (after)		1.99%
Class B decrease		(0.07%)
Class C (before)		2.06%
Class C (after)		1.99%
Class C decrease		(0.07%)
Class R (before)		1.56%
Class R (after)		1.49%
Class R decrease		(0.07%)
Advisor Class (before)		1.06%
Advisor Class (after)		0.99%
Advisor Class decrease		(0.07%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Moderate-Conservative

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.22%		0.22%		0.22%		0.22%		0.22%
Acquired Fund Fees and Expenses1		0.64%		0.64%		0.64%		0.64%		0.64%
Total Annual Fund Operating Expenses		1.31%		2.06%		2.06%		1.56%		1.06%
Less Expense Reimbursement2		(0.07%)		(0.07%)		(0.07%)		(0.07%)		(0.07%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.24%		1.99%		1.99%		1.49%		0.99%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	702	$	302	$	152	$	101
3 years	$	936	$	1,039	$	639	$	486	$	330
5 years	$	1,222	$	1,302	$	1,102	$	843	$	578
10 years	$	2,036	$	2,192	$	2,384	$	1,851	$	1,288

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	669	$	202	$	202	$	152	$	101
3 years	$	936	$	639	$	639	$	486	$	330
5 years	$	1,222	$	1,102	$	1,102	$	843	$	578
10 years	$	2,036	$	2,192	$	2,384	$	1,851	$	1,288

Pacific Funds Portfolio Optimization Moderate-Conservative – Sector Risk is deleted from the Principal Risks from Holdings in Underlying Funds subsection.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Your expenses (in dollars) if you SELL your shares at the end of each period.

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.

Pacific Funds Portfolio Optimization Moderate-Conservative | Class A

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.31%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[4]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.24%

1 year

rr_ExpenseExampleYear01

$ 669

3 years

rr_ExpenseExampleYear03

936

5 years

rr_ExpenseExampleYear05

1,222

10 years

rr_ExpenseExampleYear10

2,036

1 year

rr_ExpenseExampleNoRedemptionYear01

669

3 years

rr_ExpenseExampleNoRedemptionYear03

936

5 years

rr_ExpenseExampleNoRedemptionYear05

1,222

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,036

Pacific Funds Portfolio Optimization Moderate-Conservative | Class B

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.06%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[4]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.99%

1 year

rr_ExpenseExampleYear01

$ 702

3 years

rr_ExpenseExampleYear03

1,039

5 years

rr_ExpenseExampleYear05

1,302

10 years

rr_ExpenseExampleYear10

2,192

1 year

rr_ExpenseExampleNoRedemptionYear01

202

3 years

rr_ExpenseExampleNoRedemptionYear03

639

5 years

rr_ExpenseExampleNoRedemptionYear05

1,102

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,192

Pacific Funds Portfolio Optimization Moderate-Conservative | Class C

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.06%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[4]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.99%

1 year

rr_ExpenseExampleYear01

$ 302

3 years

rr_ExpenseExampleYear03

639

5 years

rr_ExpenseExampleYear05

1,102

10 years

rr_ExpenseExampleYear10

2,384

1 year

rr_ExpenseExampleNoRedemptionYear01

202

3 years

rr_ExpenseExampleNoRedemptionYear03

639

5 years

rr_ExpenseExampleNoRedemptionYear05

1,102

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,384

Pacific Funds Portfolio Optimization Moderate-Conservative | Class R

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.56%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[4]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.49%

1 year

rr_ExpenseExampleYear01

$ 152

3 years

rr_ExpenseExampleYear03

486

5 years

rr_ExpenseExampleYear05

843

10 years

rr_ExpenseExampleYear10

1,851

1 year

rr_ExpenseExampleNoRedemptionYear01

152

3 years

rr_ExpenseExampleNoRedemptionYear03

486

5 years

rr_ExpenseExampleNoRedemptionYear05

843

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,851

Pacific Funds Portfolio Optimization Moderate-Conservative | Advisor Class

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.64%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.06%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[4]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

0.99%

1 year

rr_ExpenseExampleYear01

$ 101

3 years

rr_ExpenseExampleYear03

330

5 years

rr_ExpenseExampleYear05

578

10 years

rr_ExpenseExampleYear10

1,288

1 year

rr_ExpenseExampleNoRedemptionYear01

101

3 years

rr_ExpenseExampleNoRedemptionYear03

330

5 years

rr_ExpenseExampleNoRedemptionYear05

578

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,288

Pacific Funds Portfolio Optimization Moderate

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

plf_SupplementTextBlock

SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Moderate
Class A (before)		1.36%
Class A (after)		1.26%
Class A decrease		(0.10%)
Class B (before)		2.11%
Class B (after)		2.01%
Class B decrease		(0.10%)
Class C (before)		2.11%
Class C (after)		2.01%
Class C decrease		(0.10%)
Class R (before)		1.61%
Class R (after)		1.51%
Class R decrease		(0.10%)
Advisor Class (before)		1.11%
Advisor Class (after)		1.01%
Advisor Class decrease		(0.10%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Moderate

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.21%		0.21%		0.21%		0.21%		0.21%
Acquired Fund Fees and Expenses1		0.66%		0.66%		0.66%		0.66%		0.66%
Total Annual Fund Operating Expenses		1.32%		2.07%		2.07%		1.57%		1.07%
Less Expense Reimbursement2		(0.06%)		(0.06%)		(0.06%)		(0.06%)		(0.06%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.26%		2.01%		2.01%		1.51%		1.01%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	671	$	704	$	304	$	154	$	103
3 years	$	940	$	1,043	$	643	$	490	$	334
5 years	$	1,228	$	1,308	$	1,108	$	849	$	584
10 years	$	2,048	$	2,203	$	2,395	$	1,862	$	1,300

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	671	$	204	$	204	$	154	$	103
3 years	$	940	$	643	$	643	$	490	$	334
5 years	$	1,228	$	1,108	$	1,108	$	849	$	584
10 years	$	2,048	$	2,203	$	2,395	$	1,862	$	1,300

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Your expenses (in dollars) if you SELL your shares at the end of each period.

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.

Pacific Funds Portfolio Optimization Moderate | Class A

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.66%

^[5]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.32%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.06%)

^[6]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.26%

1 year

rr_ExpenseExampleYear01

$ 671

3 years

rr_ExpenseExampleYear03

940

5 years

rr_ExpenseExampleYear05

1,228

10 years

rr_ExpenseExampleYear10

2,048

1 year

rr_ExpenseExampleNoRedemptionYear01

671

3 years

rr_ExpenseExampleNoRedemptionYear03

940

5 years

rr_ExpenseExampleNoRedemptionYear05

1,228

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,048

Pacific Funds Portfolio Optimization Moderate | Class B

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.66%

^[5]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.07%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.06%)

^[6]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

2.01%

1 year

rr_ExpenseExampleYear01

$ 704

3 years

rr_ExpenseExampleYear03

1,043

5 years

rr_ExpenseExampleYear05

1,308

10 years

rr_ExpenseExampleYear10

2,203

1 year

rr_ExpenseExampleNoRedemptionYear01

204

3 years

rr_ExpenseExampleNoRedemptionYear03

643

5 years

rr_ExpenseExampleNoRedemptionYear05

1,108

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,203

Pacific Funds Portfolio Optimization Moderate | Class C

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.66%

^[5]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.07%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.06%)

^[6]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

2.01%

1 year

rr_ExpenseExampleYear01

$ 304

3 years

rr_ExpenseExampleYear03

643

5 years

rr_ExpenseExampleYear05

1,108

10 years

rr_ExpenseExampleYear10

2,395

1 year

rr_ExpenseExampleNoRedemptionYear01

204

3 years

rr_ExpenseExampleNoRedemptionYear03

643

5 years

rr_ExpenseExampleNoRedemptionYear05

1,108

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,395

Pacific Funds Portfolio Optimization Moderate | Class R

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.66%

^[5]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.57%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.06%)

^[6]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.51%

1 year

rr_ExpenseExampleYear01

$ 154

3 years

rr_ExpenseExampleYear03

490

5 years

rr_ExpenseExampleYear05

849

10 years

rr_ExpenseExampleYear10

1,862

1 year

rr_ExpenseExampleNoRedemptionYear01

154

3 years

rr_ExpenseExampleNoRedemptionYear03

490

5 years

rr_ExpenseExampleNoRedemptionYear05

849

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,862

Pacific Funds Portfolio Optimization Moderate | Advisor Class

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.66%

^[5]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.07%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.06%)

^[6]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.01%

1 year

rr_ExpenseExampleYear01

$ 103

3 years

rr_ExpenseExampleYear03

334

5 years

rr_ExpenseExampleYear05

584

10 years

rr_ExpenseExampleYear10

1,300

1 year

rr_ExpenseExampleNoRedemptionYear01

103

3 years

rr_ExpenseExampleNoRedemptionYear03

334

5 years

rr_ExpenseExampleNoRedemptionYear05

584

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,300

Pacific Funds Portfolio Optimization Growth

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

plf_SupplementTextBlock

SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Growth
Class A (before)		1.41%
Class A (after)		1.28%
Class A decrease		(0.13%)
Class B (before)		2.16%
Class B (after)		2.03%
Class B decrease		(0.13%)
Class C (before)		2.16%
Class C (after)		2.03%
Class C decrease		(0.13%)
Class R (before)		1.66%
Class R (after)		1.53%
Class R decrease		(0.13%)
Advisor Class (before)		1.16%
Advisor Class (after)		1.03%
Advisor Class decrease		(0.13%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Growth

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.22%		0.22%		0.22%		0.22%		0.22%
Acquired Fund Fees and Expenses1		0.68%		0.68%		0.68%		0.68%		0.68%
Total Annual Fund Operating Expenses		1.35%		2.10%		2.10%		1.60%		1.10%
Less Expense Reimbursement2		(0.07%)		(0.07%)		(0.07%)		(0.07%)		(0.07%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.28%		2.03%		2.03%		1.53%		1.03%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	673	$	706	$	306	$	156	$	105
3 years	$	948	$	1,051	$	651	$	498	$	343
5 years	$	1,242	$	1,322	$	1,122	$	864	$	599
10 years	$	2,079	$	2,234	$	2,426	$	1,894	$	1,334

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	673	$	206	$	206	$	156	$	105
3 years	$	948	$	651	$	651	$	498	$	343
5 years	$	1,242	$	1,122	$	1,122	$	864	$	599
10 years	$	2,079	$	2,234	$	2,426	$	1,894	$	1,334

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Your expenses (in dollars) if you SELL your shares at the end of each period.

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.

Pacific Funds Portfolio Optimization Growth | Class A

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.68%

^[7]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.35%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[8]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.28%

1 year

rr_ExpenseExampleYear01

$ 673

3 years

rr_ExpenseExampleYear03

948

5 years

rr_ExpenseExampleYear05

1,242

10 years

rr_ExpenseExampleYear10

2,079

1 year

rr_ExpenseExampleNoRedemptionYear01

673

3 years

rr_ExpenseExampleNoRedemptionYear03

948

5 years

rr_ExpenseExampleNoRedemptionYear05

1,242

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,079

Pacific Funds Portfolio Optimization Growth | Class B

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.68%

^[7]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.10%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[8]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

2.03%

1 year

rr_ExpenseExampleYear01

$ 706

3 years

rr_ExpenseExampleYear03

1,051

5 years

rr_ExpenseExampleYear05

1,322

10 years

rr_ExpenseExampleYear10

2,234

1 year

rr_ExpenseExampleNoRedemptionYear01

206

3 years

rr_ExpenseExampleNoRedemptionYear03

651

5 years

rr_ExpenseExampleNoRedemptionYear05

1,122

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,234

Pacific Funds Portfolio Optimization Growth | Class C

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.68%

^[7]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.10%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[8]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

2.03%

1 year

rr_ExpenseExampleYear01

$ 306

3 years

rr_ExpenseExampleYear03

651

5 years

rr_ExpenseExampleYear05

1,122

10 years

rr_ExpenseExampleYear10

2,426

1 year

rr_ExpenseExampleNoRedemptionYear01

206

3 years

rr_ExpenseExampleNoRedemptionYear03

651

5 years

rr_ExpenseExampleNoRedemptionYear05

1,122

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,426

Pacific Funds Portfolio Optimization Growth | Class R

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.68%

^[7]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.60%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[8]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.53%

1 year

rr_ExpenseExampleYear01

$ 156

3 years

rr_ExpenseExampleYear03

498

5 years

rr_ExpenseExampleYear05

864

10 years

rr_ExpenseExampleYear10

1,894

1 year

rr_ExpenseExampleNoRedemptionYear01

156

3 years

rr_ExpenseExampleNoRedemptionYear03

498

5 years

rr_ExpenseExampleNoRedemptionYear05

864

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,894

Pacific Funds Portfolio Optimization Growth | Advisor Class

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.22%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.68%

^[7]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.10%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.07%)

^[8]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.03%

1 year

rr_ExpenseExampleYear01

$ 105

3 years

rr_ExpenseExampleYear03

343

5 years

rr_ExpenseExampleYear05

599

10 years

rr_ExpenseExampleYear10

1,334

1 year

rr_ExpenseExampleNoRedemptionYear01

105

3 years

rr_ExpenseExampleNoRedemptionYear03

343

5 years

rr_ExpenseExampleNoRedemptionYear05

599

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,334

Pacific Funds Portfolio Optimization Aggressive-Growth

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

plf_SupplementTextBlock

SUPPLEMENT DATED NOVEMBER 28, 2017

TO THE PROSPECTUS DATED AUGUST 1, 2017

FOR PACIFIC FUNDS CLASS A, CLASS B, CLASS C, CLASS I, CLASS R,

ADVISOR CLASS and INVESTOR CLASS SHARES

This supplement revises the Pacific Funds Class A, Class B, Class C, Class I, Class R, Advisor Class and Investor Class shares prospectus dated August 1, 2017 (the “Prospectus”), and must be preceded or accompanied by the Prospectus. Unless otherwise noted, the changes within this supplement apply to Pacific Funds^SM Portfolio Optimization Conservative, Pacific Funds^SM Portfolio Optimization Moderate-Conservative, Pacific Funds^SM Portfolio Optimization Moderate, Pacific Funds^SM Portfolio Optimization Growth and Pacific Funds^SM Portfolio Optimization Aggressive-Growth (the “Portfolio Optimization Funds”) and will be effective on or about January 31, 2018. Remember to review the Prospectus for other important information. Capitalized terms not defined herein are as defined in the Prospectus.

As further described below, Pacific Life Fund Advisors LLC, the investment adviser to the Trust (“PLFA”), intends to allocate the Portfolio Optimization Funds’ assets away from certain Underlying Funds and invest those assets instead in one or both of two newly created Underlying Funds. These new Underlying Funds seek to obtain broad-based market exposure principally through the use of total return swap transactions. This change is expected to lower the Portfolio Optimization Funds’ net expenses. PLFA believes that the Portfolio Optimization Funds can achieve similar returns with lower expenses by investing in the new Underlying Funds in place of certain Underlying Funds.

New Underlying Funds

Two new Underlying Funds will be added as investment options for the Portfolio Optimization Funds: the PF Multi-Asset Fund and PF Multi-Fixed Income Fund (each a “Multi-Asset Fund” and together, the “Multi-Asset Funds”). The Multi-Asset Funds are intended to provide the Portfolio Optimization Funds with the ability to obtain exposure to certain broad asset class categories (or “market segments”) by using derivatives, principally total return swap agreements, at a lower cost than by investing in certain actively managed Underlying Funds that invest principally in securities of companies within these same market segments (the existing structure). By investing in the Multi-Asset Funds to obtain exposure to the desired market segments, and by actively allocating the Multi-Asset Funds’ investments in these market segments based on PLFA’s investment views, PLFA believes that the Portfolio Optimization Funds can achieve similar returns, at a lower cost, than by investing in the current Underlying Funds. Investing in the Multi-Asset Funds may also allow the Portfolio Optimization Funds to experience lower transaction costs when rebalancing their portfolios because PLFA will be able to adjust a Portfolio Optimization Fund’s market segment exposures through the use of swap transactions by the Multi-Asset Funds rather than by adjusting allocations to Underlying Funds. This is expected to reduce the purchases and sales of Underlying Fund shares by the Portfolio Optimization Funds and the purchases and sales of portfolio securities by the Underlying Funds.

Transitioning into the Multi-Asset Funds and out of Certain Underlying Funds

Once the PF Multi-Asset Fund has commenced operations on or about January 31, 2018, PLFA expects to redeem and reduce, and in some instances eliminate, the Portfolio Optimization Funds’ investments in certain existing Underlying Funds and invest those assets in the PF Multi-Asset Fund over a period of several months. It is anticipated that Pacific Funds Portfolio Optimization Moderate-Conservative, Pacific Funds Portfolio Optimization Moderate, Pacific Funds Portfolio Optimization Growth and Pacific Funds Portfolio Optimization Aggressive-Growth will each have a sizeable allocation to the PF Multi-Asset Fund (in excess of 25% of the applicable Portfolio Optimization Fund’s total assets).

The PF Multi-Fixed Income Fund may commence operations at a later date. At that time, PLFA may determine to allocate a portion of the Portfolio Optimization Funds’ assets away from certain existing Underlying Funds to the PF Multi-Fixed Income Fund, especially Pacific Funds Portfolio Optimization Conservative and Pacific Funds Portfolio Optimization Moderate-Conservative.

The percentages allocated by each Portfolio Optimization Fund to the two Multi-Asset Funds and the timing of those allocations will differ based on the Portfolio Optimization Fund’s specific risk/return profile and investment goal, as well as PLFA’s assessment of current and future market conditions. After the allocations to the Multi-Asset Funds are completed, the Portfolio Optimization Funds expect to remain broadly diversified with investment in approximately 18-22 actively managed Underlying Funds which engage in individual investment selection, though subsequent allocations are subject to PLFA’s investment views.

The Multi-Asset Funds’ investment strategies

The PF Multi-Asset Fund will enter into total return swap agreements to gain exposure to the large-capitalization and mid-capitalization market segments of the U.S. and developed non-U.S. equity markets, including growth and value styles. The PF Multi-Fixed Income Fund will enter into total return swap agreements to gain exposure to the market segments representing the broad U.S. investment grade bond and U.S. inflation-indexed debt securities markets, including U.S. Treasury Inflation Protected Securities. While PLFA currently believes the likelihood is low that it will use other instruments in place of the total return swaps, PLFA may purchase or sell futures or exchange-traded funds (or total return swaps on exchange-traded funds) as an alternative to the total return swaps if it determines that such instruments should be used to obtain these exposures.

PLFA allocates each Multi-Asset Fund’s assets among the abovementioned market segments based on its investment views, which take into account various factors that span across different time horizons. In determining the market outlook for each market segment across these factors, PLFA employs a combination of fundamental and quantitative research. Fundamental research covers macroeconomic, geopolitical, and asset-class specific topics. Quantitative research forms the basis for models that analyze a diverse array of economic and market data to produce actionable investment views. PLFA may increase or decrease a Fund’s exposure to a market segment in order to seek to capture upside opportunities, mitigate risk from disruptive market events, or for other reasons consistent with the Fund’s investment goal.

A significant portion of each Multi-Asset Fund’s assets serves as collateral for the Fund’s derivative positions. The collateral is managed by Pacific Asset Management and will normally be invested in investment grade debt securities, including corporate debt, asset-backed securities, mortgage-related securities, U.S. government securities and agency securities, and cash and cash equivalents. These holdings may earn some income for the Fund. Under normal circumstances, the derivatives collateral for each Fund is expected to maintain an average credit quality of A+ by Standard & Poor’s or of equivalent rating by Moody’s or Fitch and a weighted average duration between 1 and 2.75 years.

Please refer to the Multi-Asset Funds’ prospectus for additional information regarding the Funds’ principal investment strategies and risks.

No change to the Portfolio Optimization Funds’ investment goals or asset allocation process

PLFA will continue to actively manage the Portfolio Optimization Funds by investing in different market segments through various Underlying Funds, including the Multi-Asset Funds, to meet the existing investment goals of the Portfolio Optimization Funds. This includes increasing, decreasing or eliminating a Portfolio Optimization Fund’s exposure to a market segment or to a particular Underlying Fund, or changing allocations among all the Underlying Funds, based on various factors PLFA considers in making investment decisions for the Funds. PLFA will continue to use its proprietary multi-step process involving asset allocation, portfolio construction and investment risk management to position, rotate and adjust each Portfolio Optimization Fund’s positions among market segments.

Total Annual Fund Operating Expenses

The Total Annual Fund Operating Expenses after Expense Reimbursement for each Portfolio Optimization Fund are expected to decrease upon completion of the allocation of the Funds’ investments to the PF Multi-Asset Fund, as described in the following table. The revised Annual Fund Operating Expenses tables are shown further below in this supplement. The tables do not reflect any changes in expenses to the Portfolio Optimization Funds that may occur in connection with any future investment in the PF Multi-Fixed Income Fund because this Fund may commence operations at a later date. Further expense changes, if any, will be reflected in a subsequent prospectus supplement or update.

Total Annual Fund Operating Expenses after Expense Reimbursement (%) Before/After Allocation to the PF Multi-Asset Fund*	Pacific Funds Portfolio Optimization Aggressive- Growth
Class A (before)		1.44%
Class A (after)		1.31%
Class A decrease		(0.13%)
Class B (before)		2.19%
Class B (after)		2.06%
Class B decrease		(0.13%)
Class C (before)		2.19%
Class C (after)		2.06%
Class C decrease		(0.13%)
Class R (before)		1.69%
Class R (after)		1.56%
Class R decrease		(0.13%)
Advisor Class (before)		1.19%
Advisor Class (after)		1.06%
Advisor Class decrease		(0.13%)

* The expenses shown “After Allocation to the PF Multi-Asset Fund” are based on estimated expenses of the PF Multi-Asset Fund and do not reflect any changes in expenses that may occur in connection with any future investment in the PF Multi-Fixed Income Fund.

Disclosure Changes to the Fund Summaries section

Portfolio Optimization Funds – Effective upon the allocations to the PF Multi-Asset Fund being completed as discussed herein, the Annual Fund Operating Expenses tables and Examples tables are replaced with the tables below.

Pacific Funds Portfolio Optimization Aggressive-Growth

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Share Class
	A		B		C		R		Advisor
Management Fee		0.20%		0.20%		0.20%		0.20%		0.20%
Distribution (12b-1) and/or Service Fees		0.25%		1.00%		1.00%		0.50%		None
Other Expenses		0.23%		0.23%		0.23%		0.23%		0.23%
Acquired Fund Fees and Expenses1		0.71%		0.71%		0.71%		0.71%		0.71%
Total Annual Fund Operating Expenses		1.39%		2.14%		2.14%		1.64%		1.14%
Less Expense Reimbursement2		(0.08%)		(0.08%)		(0.08%)		(0.08%)		(0.08%)
Total Annual Fund Operating Expenses after Expense Reimbursement		1.31%		2.06%		2.06%		1.56%		1.06%

¹  Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

²  The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Your expenses (in dollars) if you SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	676	$	709	$	309	$	159	$	108
3 years	$	958	$	1,062	$	662	$	509	$	354
5 years	$	1,261	$	1,342	$	1,142	$	884	$	620
10 years	$	2,120	$	2,275	$	2,466	$	1,937	$	1,379

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.
	Share Class
	A		B		C		R		Advisor
1 year	$	676	$	209	$	209	$	159	$	108
3 years	$	958	$	662	$	662	$	509	$	354
5 years	$	1,261	$	1,142	$	1,142	$	884	$	620
10 years	$	2,120	$	2,275	$	2,466	$	1,937	$	1,379

Pacific Funds Portfolio Optimization Aggressive-Growth – Forward Commitments Risk is deleted from and the following risks are added to the Principal Risks from Holdings in Underlying Funds subsection:

• Credit Risk: An issuer or guarantor of a debt instrument might be unable or unwilling to meet its financial obligations and might not make interest or principal payments on an instrument when those payments are due (“default”). Defaults may potentially reduce an Underlying Fund’s income or ability to recover amounts due and may reduce the value of the debt instrument, sometimes dramatically.

• Debt Securities Risk: Debt securities and other debt instruments are subject to many risks, including interest rate risk, market and regulatory risk, credit risk, price volatility risk, and liquidity risk, which may affect their value.

• Interest Rate Risk: The value of fixed income investments may fall when interest rates rise. Debt instruments with longer durations tend to be more sensitive to changes in interest rates, making them more volatile than debt instruments with shorter durations or floating or adjustable interest rates.

• Mortgage-Related and Other Asset-Backed Securities Risk: Mortgage-related and other asset-backed securities are subject to certain risks. The value of these securities will be influenced by the factors affecting the housing market or the market for the assets underlying such securities. As a result, during periods of declining asset value, difficult or frozen credit markets, swings in interest rates, or deteriorating economic conditions, these securities may decline in value, become difficult to value, become more volatile and/or become illiquid. These securities are also subject to extension risk, where borrowers or issuers may pay principal later than expected, causing these securities to lengthen in duration and be more volatile in rising interest rate conditions. These securities are also subject to prepayment and call risk, where borrowers or issuers, respectively, may pay principal sooner than expected, causing proceeds to be reinvested at lower prevailing interest rates.

• Swap Agreements Risk: Swap agreements are derivative contracts where the parties agree to exchange the returns earned on specific assets, such as the return on, or increase in value of, an amount invested in a particular foreign currency, or in a “basket” of securities representing a certain index, or at a specific interest rate. As a derivative, it is subject to derivatives risk, including counterparty risk.

• U.S. Government Securities Risk: Not all U.S. government securities are backed or guaranteed by the U.S. government and different U.S. government securities are subject to varying degrees of credit risk. There is risk that the U.S. government will not make timely payments on its debt or provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if those entities are not able to meet their financial obligations.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Your expenses (in dollars) if you SELL your shares at the end of each period.

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

Your expenses (in dollars) if you DON’T SELL your shares at the end of each period.

Pacific Funds Portfolio Optimization Aggressive-Growth | Class A

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.71%

^[9]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.39%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[10]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.31%

1 year

rr_ExpenseExampleYear01

$ 676

3 years

rr_ExpenseExampleYear03

958

5 years

rr_ExpenseExampleYear05

1,261

10 years

rr_ExpenseExampleYear10

2,120

1 year

rr_ExpenseExampleNoRedemptionYear01

676

3 years

rr_ExpenseExampleNoRedemptionYear03

958

5 years

rr_ExpenseExampleNoRedemptionYear05

1,261

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,120

Pacific Funds Portfolio Optimization Aggressive-Growth | Class B

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.71%

^[9]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.14%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[10]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

2.06%

1 year

rr_ExpenseExampleYear01

$ 709

3 years

rr_ExpenseExampleYear03

1,062

5 years

rr_ExpenseExampleYear05

1,342

10 years

rr_ExpenseExampleYear10

2,275

1 year

rr_ExpenseExampleNoRedemptionYear01

209

3 years

rr_ExpenseExampleNoRedemptionYear03

662

5 years

rr_ExpenseExampleNoRedemptionYear05

1,142

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,275

Pacific Funds Portfolio Optimization Aggressive-Growth | Class C

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.71%

^[9]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.14%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[10]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

2.06%

1 year

rr_ExpenseExampleYear01

$ 309

3 years

rr_ExpenseExampleYear03

662

5 years

rr_ExpenseExampleYear05

1,142

10 years

rr_ExpenseExampleYear10

2,466

1 year

rr_ExpenseExampleNoRedemptionYear01

209

3 years

rr_ExpenseExampleNoRedemptionYear03

662

5 years

rr_ExpenseExampleNoRedemptionYear05

1,142

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 2,466

Pacific Funds Portfolio Optimization Aggressive-Growth | Class R

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.71%

^[9]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.64%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[10]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.56%

1 year

rr_ExpenseExampleYear01

$ 159

3 years

rr_ExpenseExampleYear03

509

5 years

rr_ExpenseExampleYear05

884

10 years

rr_ExpenseExampleYear10

1,937

1 year

rr_ExpenseExampleNoRedemptionYear01

159

3 years

rr_ExpenseExampleNoRedemptionYear03

509

5 years

rr_ExpenseExampleNoRedemptionYear05

884

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,937

Pacific Funds Portfolio Optimization Aggressive-Growth | Advisor Class

Risk/Return:

rr_RiskReturnAbstract

Management Fee

rr_ManagementFeesOverAssets

0.20%

Distribution (12b-1) and/or Service Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.71%

^[9]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.14%

Less Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[10]

Total Annual Fund Operating Expenses after Expense Reimbursement

rr_NetExpensesOverAssets

1.06%

1 year

rr_ExpenseExampleYear01

$ 108

3 years

rr_ExpenseExampleYear03

354

5 years

rr_ExpenseExampleYear05

620

10 years

rr_ExpenseExampleYear10

1,379

1 year

rr_ExpenseExampleNoRedemptionYear01

108

3 years

rr_ExpenseExampleNoRedemptionYear03

354

5 years

rr_ExpenseExampleNoRedemptionYear05

620

10 years

rr_ExpenseExampleNoRedemptionYear10

$ 1,379

[1] Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

[2] The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

[3] Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

[4] The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

[5] Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

[6] The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

[7] Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

[8] The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

[9] Acquired Fund Fees and Expenses are expenses incurred indirectly by the Fund through its ownership of shares in other investment companies. As such, they are not reflected in the total annual operating expenses in the Fund’s financial statements.

[10] The investment adviser has agreed to limit certain “Other Expenses” incurred by the Fund that exceed an annual rate of 0.15% through 7/31/2018, and 0.30% from 8/1/2018 through 7/31/2023 for Class A, B, C, R and Advisor Class shares. The agreement is terminable upon approval of the Board of Trustees and prior written notice to the investment adviser. The investment adviser may recoup from the Fund amounts reimbursed in future periods, not to exceed three years from the date on which the reimbursement took place, provided that such recoupment would be limited to the lesser of: (i) the expense cap in effect at the time of the reimbursement or (ii) the expense cap in effect at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	PACIFIC FUNDS SERIES TRUST
Prospectus Date	rr_ProspectusDate	Aug. 01, 2017
Document Creation Date	dei_DocumentCreationDate	Nov. 28, 2017