485BPOS

As filed with the Securities and Exchange Commission on October 9, 2018

File No. 333-146827

File No. 811-22135

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM  N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933		[	X	]
Pre-Effective Amendment No.		[		]
Post-Effective Amendment No.	178	[	X	]

and/or

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940		[	X	]
Amendment No.	179	[	X	]

Innovator ETFs Trust

(Exact Name of Registrant as Specified in Charter)

120 North Hale Street, Suite 200

Wheaton, Illinois 60187

(Address of Principal Executive Offices) (Zip Code)

Registrant's Telephone Number, including Area Code: (800) 621-1675

Corporation Service Company

2711 Centerville Road, Suite 400

Wilmington, Delaware 19808

(Name and Address of Agent for Service)

With Copies to:

Morrison C. Warren, Esq.

Chapman and Cutler LLP

111 West Monroe Street

Chicago, Illinois 60603

It is proposed that this filing will become effective (check appropriate box):

[ X]	immediately upon filing pursuant to paragraph (b).
[    ]	on (date) pursuant to paragraph (b).
[    ]	60 days after filing pursuant to paragraph (a)(1).
[    ]	on (date) pursuant to paragraph (a)(1).
[    ]	75 days after filing pursuant to paragraph (a)(2).
[    ]	on (date) pursuant to paragraph (a)(2) of rule 485.

If appropriate check the following box:

[    ] This post-effective amendment designates a new effective date for a previously filed post-effective amendment.

Explanatory Note:

This Post-Effective Amendment (“PEA”) No. 178 to the Registration Statement of Innovator ETFs Trust (the “Trust”) on Form N-1A hereby incorporates Parts A, B and C from the Trust’s PEA No. 175 on Form N‑1A filed on October 1, 2018.  This PEA No. 178 is filed for the sole purpose of submitting the XBRL exhibit for the risk/return summary first provided in PEA No. 175 to the Trust’s Registration Statement.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended (the “1933 Act”), and the Investment Company Act of 1940, as amended, the Registrant certifies that it meets all of the requirements for effectiveness of this Amendment to the Registration Statement under Rule 485(b) under the 1933 Act, and has duly caused this Amendment to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Wheaton and State of Illinois on October 9, 2018.

Innovator ETFs Trust

By: /s/ H. Bruce Bond

H. Bruce Bond

President

Pursuant to the requirements of the 1933 Act, this Registration Statement has been signed below by the following persons in the capacities and on the date(s) indicated:

Signature	Title	Date
/s/ H. Bruce Bond	Chief Executive Officer, President and Trustee	October 9, 2018
H. Bruce Bond
/s/ John Southard	Vice President, Treasurer and Principal Financial Accounting Officer	October 9, 2018
John Southard
Mark Berg*	Trustee	October 9, 2018
Mark Berg
Joe Stowell*	Trustee	October 9, 2018
Joe Stowell
Brian Wildman*	Trustee	October 9, 2018
Brian Wildman

*By:	/s/ H. Bruce Bond
	H. Bruce Bond
	Attorney-in-Fact pursuant to Powers of Attorney previously filed and incorporated by reference.

INDEX TO EXHIBITS

Exhibit	Exhibit No.
Instance Document	EX-101.INS
Schema Document	EX-101.SCH
Calculation Linkbase Document	EX-101.CAL
Definition Linkbase Document	EX-101.DEF
Label Linkbase Document	EX-101.LAB
Presentation Linkbase Document	EX-101.PRE

XML

Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Oct. 01, 2018
Registrant Name	Innovator ETFs Trust
Central Index Key	0001415726
Amendment Flag	false
Document Creation Date	Oct. 01, 2018
Document Effective Date	Oct. 01, 2018
Prospectus Date	Oct. 01, 2018
Innovator S&P 500 Buffer ETF - October | Innovator S&P 500 Buffer ETF - October
Prospectus:
Trading Symbol	BOCT

XML

Innovator S&P 500 Buffer ETF - October

Innovator S&P 500 Buffer ETF - October

Investment Objective

The Fund seeks to provide investors with returns that match those of the S&P 500 Price Index, up to the upside cap of 15.30% (prior to taking into account management fees and other fees) and 14.51% (after taking into account management fees and other fees) while providing a buffer against the first 9% of S&P 500 Price Index losses, over the period from October 1, 2018 to September 30, 2019.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund (“Shares”). Investors may pay brokerage commissions on their purchases and sales of Shares, which are not reflected in the table or the example below.

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

Annual Fund Operating Expenses	Innovator S&P 500 Buffer ETF - October Innovator S&P 500 Buffer ETF - October
Management Fees	0.79%
Distribution and Service (12b-1) Fees	none
Other Expenses	none	[1]
Total Annual Fund Operating Expenses	0.79%

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds.

This example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your Shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain at current levels. This example does not include the brokerage commissions that investors may pay to buy and sell Shares.

Although your actual costs may be higher or lower, your costs, based on these assumptions, would be:

Expense Example	1 Year	3 Years
Innovator S&P 500 Buffer ETF - October | Innovator S&P 500 Buffer ETF - October | USD ($)	80	251

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it purchases and sells securities (or “turns over” its portfolio). A higher portfolio turnover will cause the Fund to incur additional transaction costs and may result in higher taxes when Shares are held in a taxable account. These costs, which are not reflected in Total Annual Fund Operating Expenses or in the example, may affect the Fund’s performance. Because the Fund has not yet commenced investment operations, no portfolio turnover information is available at this time.

Principal Investment Strategies

General Strategy Description. The Fund invests at least 80% of its net assets in FLexible EXchange^® Options (“FLEX Options”) that reference the S&P 500 Price Return Index (“S&P 500 Price Index”). FLEX Options are exchange-traded options contracts with uniquely customizable terms. Although guaranteed for settlement by the Options Clearing Corporation (the “OCC”), FLEX Options are still subject to counterparty risk with the OCC and may be less liquid than more traditional exchange-traded options. Due to the unique mechanics of the Fund’s strategy, the return an investor can expect to receive from an investment in the Fund has characteristics that are distinct from many other investment vehicles. It is important that an investor understand these characteristics before making an investment in the Fund.

In general, an option contract is an agreement between a buyer and seller that gives the purchaser of the option the right to buy or sell a particular asset at a specified future date at an agreed upon price. The reference asset for all of the Fund’s FLEX Options is the S&P 500 Price Index, a large-cap, market-weighted, U.S. equities index that tracks the price (excluding dividends) of the 500 leading companies in leading industries.

The pre-determined outcomes sought by the Fund, which include the buffer and Cap discussed below, are based upon the performance of the S&P 500 Price Index over the period of October 1, 2018 through September 30, 2019. This period is referred to as the initial “Outcome Period.” Following the initial Outcome Period, each subsequent Outcome Period will be a one-year period from October 1 to September 30. In the event that the S&P 500 Price Index experiences gains over the Outcome Period, the strategy seeks to provide investment returns that match the performance of the S&P 500 Price Index, up to an upside return cap that represents the maximum percentage return an investor can achieve from an investment in the Fund for the Outcome Period (the “Cap”). The Cap is set on the first day of the Outcome Period and is 15.30% prior to taking into account any fees or expenses charged to shareholders. When the Fund’s annual Fund management fee of 0.79% of the Fund’s average daily net assets is taken into account, the Cap is 14.51%. The Cap will be further reduced by any shareholder transaction fees and any extraordinary expenses incurred by the Fund. The date stipulated in all of the Fund’s FLEX Options is the approximate termination date of the Outcome Period, at which time the Fund will invest in a new set of FLEX Options for the next Outcome Period.

The Fund’s investment sub-adviser, Milliman Financial Risk Management LLC (“Milliman” or the “Sub-Adviser”), has constructed a portfolio principally composed of seven FLEX Options on the S&P 500 Price Index that are each set to expire on the last day of the Outcome Period. The customizable nature of FLEX Options allows the Sub-Adviser to select the price at which the S&P 500 Price Index will be exercised at the expiration of each FLEX Option. This is commonly known as the “strike price.” At the commencement of the Outcome Period, the Sub-Adviser specifically selects the strike price for each FLEX Option such that when the FLEX Options are exercised on the final day of the Outcome Period, the Outcomes may be obtained, depending on the performance of the S&P 500 Price Index over the duration of the Outcome Period.

The Fund seeks to generate returns that match the S&P 500 Price Index, up to the Cap (discussed in detail below), while limiting downside losses. The two hypothetical graphical illustrations provided below are designed to illustrate the Outcomes based upon the hypothetical performance of the S&P 500 Price Index for a shareholder that holds Shares for the entirety of the Outcome Period. Additional hypothetical graphical representations of the Outcomes are provided in “Additional Information Regarding the Fund’s Principal Investment Strategies.” There is no guarantee that the Fund will be successful in its attempt to provide the Outcomes for an Outcome Period. The returns that the Fund seeks to provide do not include the costs associated with purchasing shares of the Fund and certain expenses incurred by the Fund.

[graphics omitted]

Use of FLEX Options. The Outcomes may be achieved by purchasing and selling call and put FLEX Options to create layers within the Fund’s portfolio. One layer is designed to produce returns that match those of the S&P 500 Price Index for the Outcome Period if the S&P 500 Price Index has experienced gains during that time. To achieve these returns, the Fund will purchase a call option (giving the Fund the right to receive the cash value of the S&P 500 Price Index) and a put option (giving the Fund the right to deliver the cash value of the S&P 500 Price Index), while simultaneously selling a call option (giving the Fund the obligation to deliver the cash value of the S&P 500 Price Index) and a put option (giving the Fund the obligation to receive the cash value of the S&P 500 Price Index). Each of these FLEX Options has a specifically selected strike price. The effect created by these four positions is that if the S&P 500 Price Index has increased in value over the course of the Outcome Period, when the amount of cash the Fund receives and delivers pursuant to the terms of its positions is netted out, the Fund seeks to provide a gain that matches the gain experienced by the S&P 500 Price Index. This gain is subject to the Cap, a maximum investment return level, which is discussed below.

A separate layer is designed to produce the Fund’s objective to provide returns that are buffered by up to 9% if the S&P 500 Price Index experiences a loss during the course of the Outcome Period. There is no guarantee that the Fund will be successful in its attempt to provide buffered returns. The buffer that the Fund seeks to provide is only operative against the first 9% of S&P 500 Price Index losses for the Outcome Period. After the S&P 500 Price Index has decreased in value by more than 9%, the Fund will experience all subsequent losses on a one-to-one basis. In seeking to achieve the buffer, the Fund sells both a call option and a put option. Both of these FLEX Options have a specifically selected strike price. The effect created by these two positions is that if the S&P 500 Price Index has decreased in value over the course of the Outcome Period, when the amount of cash the Fund receives and delivers pursuant to the terms of its positions is netted out, the Fund seeks to be returned the amount of its principal investment (if the S&P 500 Price Return Index decreased in value by 9% or less) or experience a loss that is 9% less than the loss experienced by the S&P 500 Price Index (if the S&P 500 Price Return Index decreased in value by more than 9%).

Each of the FLEX Options purchased and sold throughout the Outcome Period will have the same terms (i.e., strike price and expiration) as the corresponding FLEX Options purchased and sold on the first day of the Outcome Period. A detailed explanation regarding the terms of the FLEX Options and the mechanics of the Fund’s strategy can be found in “Additional Information Regarding the Fund’s Principal Investment Strategies.”

The Outcome Period. The Outcomes sought by the Fund are based upon the value of the underlying FLEX Options at the time they may be exercised at the conclusion of the Outcome Period. During the Outcome Period, the value of the FLEX Options, and Fund’s net asset value (“NAV”), may be significantly different than their value at the commencement and/or conclusion of the Outcome Period. An investor that purchases Shares after the Outcome Period has commenced or sells Shares prior to the conclusion of the Outcome Period may experience Outcomes very different from those sought by the Fund for the Outcome Period. To achieve the Outcomes sought by the Fund for the Outcome Period, an investor must be holding Shares on the day that the Fund enters into the FLEX Options and on the day those FLEX Options expire. During the Outcome Period, both the Cap and buffer are fixed numbers that are calculated based upon the Fund’s NAV (which is in turn based upon the S&P 500 Price Index). As the Outcome Period transpires and the Fund’s NAV changes, an investor purchasing Shares will likely have a different return potential than the investor who purchased Shares at the beginning of the Outcome Period. This is because while the Cap and buffer for the Outcome Period remain constant, an investor purchasing Shares during the Outcome Period likely purchased Shares at a price that is different from the Fund’s NAV at the commencement of the Outcome Period.

The value of the underlying FLEX Options on any given day will be reflected in the Fund’s NAV. However, due to the way that options contracts are valued, during the Outcome Period the value of the underlying FLEX Options, and thus the Fund’s NAV, will not correlate one-to-one with the returns being experienced by the S&P 500 Price Index (for example, if the S&P 500 Price Index has decreased in value by 20% the Fund’s NAV will not necessarily have decreased by 11%). The value of the FLEX Options depends on the amount of time remaining prior to their expiration. Accordingly, the non-correlation between the Fund’s NAV and the S&P 500 Price Index may be more pronounced earlier in the Outcome Period.

Cap on Potential Upside Returns. Unlike other investment products, the potential returns an investor can receive from an investment in the Fund are subject to an upside return cap. This means that if the Fund experiences gains for the Outcome Period beyond the Cap, a shareholder will not experience those excess gains. Therefore, regardless of the performance of the S&P 500 Price Index, the Cap is the maximum return an investor can achieve from an investment in the Fund for the Outcome Period. The Cap is set on the first day of the Outcome Period and is 15.30% prior to taking into account any fees or expenses charged to shareholders. When the Fund’s annual Fund management fee of 0.79% of the Fund’s average daily net assets is taken into account, the Cap is 14.51%. The Cap will be further reduced by any shareholder transaction fees and any extraordinary expenses incurred by the Fund. The definitive Cap will be set forth on the Fund’s website at www.innovatoretfs.com/boct.

The Cap will change for each Outcome Period based upon prevailing market conditions at the beginning of the Outcome Period. The Cap, and the Fund’s position relative to it, should be considered before investing in the Fund. If an investor is considering purchasing Shares during the Outcome Period, and the Fund has already increased in value to a level near to the Cap, an investor purchasing Shares at that price has limited to no gains available for the remainder of the Outcome Period but remains vulnerable to significant downside risks.

The Cap level is a result of the design of the Fund’s principal investment strategy. In order to provide the buffer, the Fund purchases a series of put and call FLEX Options. As the purchaser of these FLEX Options, the Fund is obligated to pay a premium to the seller of those FLEX Options. However, the strategy is designed so that any premiums that the Fund is obligated to pay are offset by premiums it receives in connection with the selling of FLEX Options. On the first day of the Outcome Period when the Fund enters into its other FLEX Options positions, the portfolio managers will calculate the amount of premiums that the Fund will owe and will then go into the market and sell a FLEX Option with terms that entitle the Fund to receive a premium in an amount equal to the amount that the Fund would otherwise owe. The Cap is the strike price of that sold FLEX Option. The strike price is determined based upon prevailing market conditions at the time the Fund enters into the FLEX Options, most notably current interest rate levels, S&P 500 Price Index volatility and dividend yield, and the relationship of put and calls on the underlying FLEX Options.

Buffer. The buffer that the Fund seeks to provide is only operative against the first 9% of S&P 500 Price Index losses for the Outcome Period. There is no guarantee that the Fund will be successful in its attempt to provide buffered returns. After the S&P 500 Price Index has decreased in value by more than 9%, the Fund will experience all subsequent losses on a one-to-one basis. The buffer is provided prior to taking into account annual Fund management fees equal to 0.79% of the Fund’s daily net assets, transaction fees and any extraordinary expenses incurred by the Fund. If an investor is considering purchasing Shares during the Outcome Period, and the Fund has already decreased in value by an amount equal to or greater than 9%, an investor purchasing Shares at that price will have increased gains available prior to reaching the Cap but may not benefit from the buffer that the Fund seeks to offer for the remainder of the Outcome Period. Conversely, if an investor is considering purchasing Shares during the Outcome Period, and the Fund has already increased in value, then a shareholder may experience losses prior to gaining the protection offered by the buffer. A shareholder that purchases Shares at the beginning of the Outcome Period may lose their entire investment. While the Fund seeks to limit losses to 91% for shareholders who hold Shares for the entire Outcome Period, there is no guarantee it will successfully do so. Depending upon market conditions at the time of purchase, a shareholder that purchases Shares after the Outcome Period has begun may also lose their entire investment. An investment in the Fund is only appropriate for shareholders willing to bear those losses.

Fund Rebalance. The Fund is a continuous investment vehicle. It does not terminate and distribute its assets at the conclusion of each Outcome Period. On the termination date of an Outcome Period, the Sub-Adviser will invest in a new set of FLEX Options and another Outcome Period will commence.

The Fund’s website, www.innovatoretfs.com/boct, provides information relating to the Outcomes, including the Fund’s position relative to the Cap and buffer, of an investment in the Fund on a daily basis.

The Fund is classified as “non-diversified” under the Investment Company Act of 1940, as amended (the “1940 Act”).

Principal Risks

You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund’s investment objectives will be achieved.

Active Markets Risk. Although the Shares are listed for trading on the Exchange, there can be no assurance that an active trading market for the Shares will develop or be maintained. Shares trade on the Exchange at market prices that may be below, at or above the Fund’s NAV. Securities, including the Shares, are subject to market fluctuations and liquidity constraints that may be caused by such factors as economic, political, or regulatory developments, changes in interest rates, and/or perceived trends in securities prices. Shares of the Fund could decline in value or underperform other investments.

Authorized Participation Concentration Risk. Only an authorized participant may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as authorized participants on an agency basis (i.e., on behalf of other market participants). To the extent that authorized participants exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other authorized participant is able to step forward to create or redeem “Creation Units” (as defined in “Purchase and Sale of Shares,”) Shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts and/or delisting.

Buffered Loss Risk. There can be no guarantee that the Fund will be successful in its strategy to buffer against S&P 500 Price Index losses if the S&P 500 Price Index decreases over the Outcome Period by 9% or less. A shareholder may lose their entire investment. The Fund’s strategy seeks to deliver returns that match the S&P 500 Price Index (up to the Cap), while limiting downside losses, if Shares are bought on the day on which the Fund enters into the FLEX Options and held until those FLEX Options expire at the end of each Outcome Period. In the event an investor purchases Shares after the date on which the FLEX Options were entered into or sells Shares prior to the expiration of the FLEX Options, the buffer that the Fund seeks to provide may not be available.

Cap Change Risk. A new Cap is established at the beginning of each Outcome Period and is dependent on prevailing market conditions. As such, the Cap may rise or fall from one Outcome Period to the next and is unlikely to remain the same for consecutive Outcome Periods.

Capped Upside Return Risk. The Fund’s strategy seeks to provide returns that are subject to the Cap. In the event that the S&P 500 Price Index has gains in excess of the Cap for the Outcome Period, the Fund will not participate in those gains beyond the Cap. The Fund’s strategy seeks to deliver returns that match those of the S&P 500 Price Index if Shares are bought on the day on which the Fund enters into the FLEX Options and held until those FLEX Options expire at the end of the Outcome Period. In the event an investor purchases Shares after the date on which the FLEX Options were entered into and the Fund has risen in value to a level near to the Cap, there may be little or no ability for that investor to experience an investment gain on their Shares.

Cash Transactions Risk. The Fund intends to effectuate creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an exchange-traded fund (“ETF”) that effects its creations and redemption for in-kind securities. Because the Fund will effect redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of Shares may result in capital gains or losses and may also result in higher brokerage costs. Consequently, an investment in the Fund may be less tax-efficient than investments in other ETFs. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to purchasers and redeemers of Shares in the form of creation and redemption transaction fees. In addition, these factors may result in wider spreads between the bid and the offered prices of Shares than for other ETFs.

Correlation Risk. The FLEX Options held by the Fund will be exercisable at the strike price only on their expiration date. Prior to the expiration date, the value of the FLEX Options will be determined based upon market quotations or using other recognized pricing methods. The value of the FLEX Options prior to the expiration date may vary because of related factors other than the value of the S&P 500 Price Index. Factors that may influence the value of the FLEX Options include interest rate changes and implied volatility levels of the S&P 500 Price Index, among others.

Counterparty Risk. Counterparty risk is the risk an issuer, guarantor or counterparty of a security in the Fund is unable or unwilling to meet its obligation on the security. The OCC acts as guarantor and central counterparty with respect to the FLEX Options. As a result, the ability of the Fund to meet its objective depends on the OCC being able to meet its obligations. In the unlikely event that the OCC becomes insolvent or is otherwise unable to meet its settlement obligations, the Fund could suffer significant losses.

Cyber Security Risk. As the use of Internet technology has become more prevalent in the course of business, the investment industry has become more susceptible to potential operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund’s digital information systems through “hacking” or malicious software coding, but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the Fund’s third-party service providers, such as its administrator, transfer agent, custodian, or issuers in which the Fund invests, can also subject the Fund to many of the same risks associated with direct cyber security breaches. The Fund has established risk management systems designed to reduce the risks associated with cyber security. However, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third-party service providers.

FLEX Options Risk. The Fund will utilize FLEX Options issued and guaranteed for settlement by the OCC. The Fund bears the risk that the OCC will be unable or unwilling to perform its obligations under the FLEX Options contracts. In the unlikely event that the OCC becomes insolvent or is otherwise unable to meet its settlement obligations, the Fund could suffer significant losses. Additionally, FLEX Options may be less liquid than certain other securities such as standardized options. In less liquid market for the FLEX Options, the Fund may have difficulty closing out certain FLEX Options positions at desired times and prices. The values of FLEX Options do not increase or decrease at the same rate as the reference asset and may vary due to factors other than the price of reference asset.

Fluctuation of Net Asset Value Risk. The Fund’s Shares trade on the Exchange at their market price rather than their NAV. The market price may be at, above or below the Fund’s NAV. Differences in market price and NAV may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for Shares will be closely related to, but not identical to, the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. These differences can be especially pronounced during times of market volatility or stress. During these periods, the demand for Shares may decrease considerably and cause the market price of Shares to deviate significantly from the Fund’s NAV.

Investment Objective Risk. Certain circumstances under which the Fund might not achieve its objective include, but are not limited, to (i) if the Fund disposes of FLEX Options, (ii) if the Fund is unable to maintain the proportional relationship based on the number of FLEX Options in the Fund’s portfolio, (iii) significant accrual of Fund expenses in connection with effecting the Fund’s principal investment strategy or (iv) adverse tax law changes affecting the treatment of FLEX Options.

Limitations of Intraday Indicative Value Risk. The Exchange intends to disseminate the approximate per share value of the Fund’s published basket of portfolio securities every 15 seconds (the ‘‘intraday indicative value’’ or ‘‘IIV’’). The IIV should not be viewed as a ‘‘real-time’’ update of the NAV per Share because (i) the IIV may not be calculated in the same manner as the NAV, which is computed once a day, generally at the end of the business day, (ii) the calculation of NAV may be subject to fair valuation at different prices than those used in the calculations of the IIV, (iii) unlike the calculation of NAV, the IIV does not take into account Fund expenses, and (iv) the IIV is based on the published basket of portfolio securities and not on the Fund’s actual holdings. The IIV calculations are based on local market prices and may not reflect events that occur subsequent to the local market’s close, which could affect premiums and discounts between the IIV and the market price of the Shares. The Fund, Adviser, Sub-Adviser, and their affiliates, are not involved in, or responsible for, any aspect of the calculation or dissemination of the Fund’s IIV, and the Fund, Adviser, Sub-Adviser, and their affiliates, do not make any warranty as to the accuracy of these calculations.

Liquidity Risk. In the event that trading in the underlying FLEX Options is limited or absent, the value of the Fund’s FLEX Options may decrease. There is no guarantee that a liquid secondary trading market will exist for the FLEX Options. The trading in FLEX Options may be less deep and liquid than the market for certain other securities. FLEX Options may be less liquid than certain non-customized options. In a less liquid market for the FLEX Options, terminating the FLEX Options may require the payment of a premium or acceptance of a discounted price and may take longer to complete. In a less liquid market for the FLEX Options, the liquidation of a large number of options may more significantly impact the price. A less liquid trading market may adversely impact the value of the FLEX Options and the value of your investment.

Management Risk. The Fund is subject to management risk because it is an actively managed portfolio. The Sub-Adviser will apply investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that the Fund will meet its investment objective.

Market Maker Risk. If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of Shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s NAV and the price at which the Shares are trading on the Exchange, which could result in a decrease in value of the Shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Shares trading at a discount to NAV and also in greater than normal intra-day bid-ask spreads for Shares.

Market Risk. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns. Assets may decline in value due to factors affecting financial markets generally or particular asset classes or industries represented in the markets. The value of a FLEX Options or other asset may also decline due to general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or due to factors that affect a particular issuer or issuers, country, group of countries, region, market, industry, group of industries, sector or asset class. During a general market downturn, multiple asset classes may be negatively affected. Changes in market conditions and interest rates will not have the same impact on all types of securities.

Non-Diversification Risk. The Fund is classified as “non-diversified” under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended (the “Code”). The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error in the calculation of the Cap, processing and communication errors, errors of the Fund’s service providers, counterparties or other third-parties, failed or inadequate processes and technology or systems failures. The Fund and its investment adviser and Sub-adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address these risks.

Options Risk. The value of the underlying FLEX Options will be affected by, among others, changes in the value of the S&P 500 Price Index, changes in interest rates, changes in the actual and implied volatility, as well as in dividend yields, of the S&P 500 Price Index and the remaining time to until the FLEX Options expire. The value of the FLEX Options does not increase or decrease at the same rate as the level of the S&P 500 Price Index (although they generally move in the same direction). However, as a FLEX Option approaches its expiration date, its value typically increasingly moves with the value of the S&P 500 Price Index. The Fund may experience substantial downside from specific FLEX Option positions and certain FLEX Option positions may expire worthless.

Outcome Period Risk. The Fund’s investment strategy is designed to deliver returns that match the S&P 500 Price Index if Shares are bought on the day on which the Fund enters into the FLEX Options and held until those FLEX Options expire at the end of the Outcome Period. In the event an investor purchases Shares after the date on which the FLEX Options were entered into or sells Shares prior to the expiration of the FLEX Options, the returns realized by the investor will not match those that the Fund seeks to achieve.

Tax Risk. The Fund intends to elect and to qualify each year to be treated as a regulated investment company (“RIC”) under Subchapter M of the Code. As a RIC, the Fund will not be subject to U.S. federal income tax on the portion of its net investment income and net capital gain that it distributes to unitholders, provided that it satisfies certain requirements of the Code. If the Fund does not qualify as a RIC for any taxable year and certain relief provisions are not available, the Fund’s taxable income will be subject to tax at the Fund level and to a further tax at the shareholder level when such income is distributed.

Additionally, buying securities shortly before the record date for a taxable dividend or capital gain distribution is commonly known as “buying the dividend.” In the event a shareholder purchases Shares shortly before such a distribution, the entire distribution may be taxable to the shareholder even though a portion of the distribution effectively represents a return of the purchase price.

Trading Issues Risk. Although the Shares are listed for trading on the Exchange, there can be no assurance that an active trading market for such Shares will develop or be maintained. Trading in Shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in Shares inadvisable. In addition, trading in Shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange “circuit breaker” rules. Market makers are under no obligation to make a market in the Shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. Initially, due to the small asset size of the Fund, it may have difficulty maintaining its listings on the Exchange.

Upside Participation Risk. There can be no guarantee that the Fund will be successful in its strategy to provide shareholders with a total return that matches the increase of the S&P 500 Price Index over the Outcome Period, up to the maximum return imposed by the Cap. In the event an investor purchases Shares after the date on which the FLEX Options were entered into or does not stay invested in the Fund for the entirety of the Outcome Period, the returns realized by the investor may not match those that the Fund seeks to achieve.

Valuation Risk. During periods of reduced market liquidity or in the absence of readily available market quotations for the holdings of the Fund, the ability of the Fund to value the FLEX Options becomes more difficult and the judgment of the Fund’s investment adviser (employing the fair value procedures adopted by the Board of Trustees of the Trust may play a greater role in the valuation of the Fund’s holdings due to reduced availability of reliable objective pricing data. Consequently, while such determinations may be made in good faith, it may nevertheless be more difficult for the Fund to accurately assign a daily value.

The Shares will change in value, and you could lose money by investing in the Fund. The Fund may not achieve its investment objective.

Performance

As of the date of this prospectus, the Fund has not commenced operations and therefore does not have a performance history. Once available, the Fund’s performance information will be accessible on the Fund’s website at www.innovatoretfs.com and will provide some indication of the risks of investing in the Fund.

[1] "Other Expenses" are estimates based on the expenses the Fund expects to incur for the current fiscal year.

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Innovator S&P 500 Buffer ETF - October

Risk/Return:

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Risk/Return [Heading]

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Innovator S&P 500 Buffer ETF - October

Objective [Heading]

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Investment Objective

Objective, Primary [Text Block]

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The Fund seeks to provide investors with returns that match those of the S&P 500 Price Index, up to the upside cap of 15.30% (prior to taking into account management fees and other fees) and 14.51% (after taking into account management fees and other fees) while providing a buffer against the first 9% of S&P 500 Price Index losses, over the period from October 1, 2018 to September 30, 2019.

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund (“Shares”). Investors may pay brokerage commissions on their purchases and sales of Shares, which are not reflected in the table or the example below.

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it purchases and sells securities (or “turns over” its portfolio). A higher portfolio turnover will cause the Fund to incur additional transaction costs and may result in higher taxes when Shares are held in a taxable account. These costs, which are not reflected in Total Annual Fund Operating Expenses or in the example, may affect the Fund’s performance. Because the Fund has not yet commenced investment operations, no portfolio turnover information is available at this time.

Expense Exchange Traded Fund Commissions [Text]

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Investors may pay brokerage commissions on their purchases and sales of Shares, which are not reflected in the table or the example below.

Other Expenses, New Fund, Based on Estimates [Text]

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“Other Expenses” are estimates based on the expenses the Fund expects to incur for the current fiscal year.

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds.

This example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your Shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain at current levels. This example does not include the brokerage commissions that investors may pay to buy and sell Shares.

Expense Example by, Year, Caption [Text]

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Although your actual costs may be higher or lower, your costs, based on these assumptions, would be:

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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General Strategy Description. The Fund invests at least 80% of its net assets in FLexible EXchange^® Options (“FLEX Options”) that reference the S&P 500 Price Return Index (“S&P 500 Price Index”). FLEX Options are exchange-traded options contracts with uniquely customizable terms. Although guaranteed for settlement by the Options Clearing Corporation (the “OCC”), FLEX Options are still subject to counterparty risk with the OCC and may be less liquid than more traditional exchange-traded options. Due to the unique mechanics of the Fund’s strategy, the return an investor can expect to receive from an investment in the Fund has characteristics that are distinct from many other investment vehicles. It is important that an investor understand these characteristics before making an investment in the Fund.

In general, an option contract is an agreement between a buyer and seller that gives the purchaser of the option the right to buy or sell a particular asset at a specified future date at an agreed upon price. The reference asset for all of the Fund’s FLEX Options is the S&P 500 Price Index, a large-cap, market-weighted, U.S. equities index that tracks the price (excluding dividends) of the 500 leading companies in leading industries.

The pre-determined outcomes sought by the Fund, which include the buffer and Cap discussed below, are based upon the performance of the S&P 500 Price Index over the period of October 1, 2018 through September 30, 2019. This period is referred to as the initial “Outcome Period.” Following the initial Outcome Period, each subsequent Outcome Period will be a one-year period from October 1 to September 30. In the event that the S&P 500 Price Index experiences gains over the Outcome Period, the strategy seeks to provide investment returns that match the performance of the S&P 500 Price Index, up to an upside return cap that represents the maximum percentage return an investor can achieve from an investment in the Fund for the Outcome Period (the “Cap”). The Cap is set on the first day of the Outcome Period and is 15.30% prior to taking into account any fees or expenses charged to shareholders. When the Fund’s annual Fund management fee of 0.79% of the Fund’s average daily net assets is taken into account, the Cap is 14.51%. The Cap will be further reduced by any shareholder transaction fees and any extraordinary expenses incurred by the Fund. The date stipulated in all of the Fund’s FLEX Options is the approximate termination date of the Outcome Period, at which time the Fund will invest in a new set of FLEX Options for the next Outcome Period.

The Fund’s investment sub-adviser, Milliman Financial Risk Management LLC (“Milliman” or the “Sub-Adviser”), has constructed a portfolio principally composed of seven FLEX Options on the S&P 500 Price Index that are each set to expire on the last day of the Outcome Period. The customizable nature of FLEX Options allows the Sub-Adviser to select the price at which the S&P 500 Price Index will be exercised at the expiration of each FLEX Option. This is commonly known as the “strike price.” At the commencement of the Outcome Period, the Sub-Adviser specifically selects the strike price for each FLEX Option such that when the FLEX Options are exercised on the final day of the Outcome Period, the Outcomes may be obtained, depending on the performance of the S&P 500 Price Index over the duration of the Outcome Period.

The Fund seeks to generate returns that match the S&P 500 Price Index, up to the Cap (discussed in detail below), while limiting downside losses. The two hypothetical graphical illustrations provided below are designed to illustrate the Outcomes based upon the hypothetical performance of the S&P 500 Price Index for a shareholder that holds Shares for the entirety of the Outcome Period. Additional hypothetical graphical representations of the Outcomes are provided in “Additional Information Regarding the Fund’s Principal Investment Strategies.” There is no guarantee that the Fund will be successful in its attempt to provide the Outcomes for an Outcome Period. The returns that the Fund seeks to provide do not include the costs associated with purchasing shares of the Fund and certain expenses incurred by the Fund.

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Use of FLEX Options. The Outcomes may be achieved by purchasing and selling call and put FLEX Options to create layers within the Fund’s portfolio. One layer is designed to produce returns that match those of the S&P 500 Price Index for the Outcome Period if the S&P 500 Price Index has experienced gains during that time. To achieve these returns, the Fund will purchase a call option (giving the Fund the right to receive the cash value of the S&P 500 Price Index) and a put option (giving the Fund the right to deliver the cash value of the S&P 500 Price Index), while simultaneously selling a call option (giving the Fund the obligation to deliver the cash value of the S&P 500 Price Index) and a put option (giving the Fund the obligation to receive the cash value of the S&P 500 Price Index). Each of these FLEX Options has a specifically selected strike price. The effect created by these four positions is that if the S&P 500 Price Index has increased in value over the course of the Outcome Period, when the amount of cash the Fund receives and delivers pursuant to the terms of its positions is netted out, the Fund seeks to provide a gain that matches the gain experienced by the S&P 500 Price Index. This gain is subject to the Cap, a maximum investment return level, which is discussed below.

A separate layer is designed to produce the Fund’s objective to provide returns that are buffered by up to 9% if the S&P 500 Price Index experiences a loss during the course of the Outcome Period. There is no guarantee that the Fund will be successful in its attempt to provide buffered returns. The buffer that the Fund seeks to provide is only operative against the first 9% of S&P 500 Price Index losses for the Outcome Period. After the S&P 500 Price Index has decreased in value by more than 9%, the Fund will experience all subsequent losses on a one-to-one basis. In seeking to achieve the buffer, the Fund sells both a call option and a put option. Both of these FLEX Options have a specifically selected strike price. The effect created by these two positions is that if the S&P 500 Price Index has decreased in value over the course of the Outcome Period, when the amount of cash the Fund receives and delivers pursuant to the terms of its positions is netted out, the Fund seeks to be returned the amount of its principal investment (if the S&P 500 Price Return Index decreased in value by 9% or less) or experience a loss that is 9% less than the loss experienced by the S&P 500 Price Index (if the S&P 500 Price Return Index decreased in value by more than 9%).

Each of the FLEX Options purchased and sold throughout the Outcome Period will have the same terms (i.e., strike price and expiration) as the corresponding FLEX Options purchased and sold on the first day of the Outcome Period. A detailed explanation regarding the terms of the FLEX Options and the mechanics of the Fund’s strategy can be found in “Additional Information Regarding the Fund’s Principal Investment Strategies.”

The Outcome Period. The Outcomes sought by the Fund are based upon the value of the underlying FLEX Options at the time they may be exercised at the conclusion of the Outcome Period. During the Outcome Period, the value of the FLEX Options, and Fund’s net asset value (“NAV”), may be significantly different than their value at the commencement and/or conclusion of the Outcome Period. An investor that purchases Shares after the Outcome Period has commenced or sells Shares prior to the conclusion of the Outcome Period may experience Outcomes very different from those sought by the Fund for the Outcome Period. To achieve the Outcomes sought by the Fund for the Outcome Period, an investor must be holding Shares on the day that the Fund enters into the FLEX Options and on the day those FLEX Options expire. During the Outcome Period, both the Cap and buffer are fixed numbers that are calculated based upon the Fund’s NAV (which is in turn based upon the S&P 500 Price Index). As the Outcome Period transpires and the Fund’s NAV changes, an investor purchasing Shares will likely have a different return potential than the investor who purchased Shares at the beginning of the Outcome Period. This is because while the Cap and buffer for the Outcome Period remain constant, an investor purchasing Shares during the Outcome Period likely purchased Shares at a price that is different from the Fund’s NAV at the commencement of the Outcome Period.

The value of the underlying FLEX Options on any given day will be reflected in the Fund’s NAV. However, due to the way that options contracts are valued, during the Outcome Period the value of the underlying FLEX Options, and thus the Fund’s NAV, will not correlate one-to-one with the returns being experienced by the S&P 500 Price Index (for example, if the S&P 500 Price Index has decreased in value by 20% the Fund’s NAV will not necessarily have decreased by 11%). The value of the FLEX Options depends on the amount of time remaining prior to their expiration. Accordingly, the non-correlation between the Fund’s NAV and the S&P 500 Price Index may be more pronounced earlier in the Outcome Period.

Cap on Potential Upside Returns. Unlike other investment products, the potential returns an investor can receive from an investment in the Fund are subject to an upside return cap. This means that if the Fund experiences gains for the Outcome Period beyond the Cap, a shareholder will not experience those excess gains. Therefore, regardless of the performance of the S&P 500 Price Index, the Cap is the maximum return an investor can achieve from an investment in the Fund for the Outcome Period. The Cap is set on the first day of the Outcome Period and is 15.30% prior to taking into account any fees or expenses charged to shareholders. When the Fund’s annual Fund management fee of 0.79% of the Fund’s average daily net assets is taken into account, the Cap is 14.51%. The Cap will be further reduced by any shareholder transaction fees and any extraordinary expenses incurred by the Fund. The definitive Cap will be set forth on the Fund’s website at www.innovatoretfs.com/boct.

The Cap will change for each Outcome Period based upon prevailing market conditions at the beginning of the Outcome Period. The Cap, and the Fund’s position relative to it, should be considered before investing in the Fund. If an investor is considering purchasing Shares during the Outcome Period, and the Fund has already increased in value to a level near to the Cap, an investor purchasing Shares at that price has limited to no gains available for the remainder of the Outcome Period but remains vulnerable to significant downside risks.

The Cap level is a result of the design of the Fund’s principal investment strategy. In order to provide the buffer, the Fund purchases a series of put and call FLEX Options. As the purchaser of these FLEX Options, the Fund is obligated to pay a premium to the seller of those FLEX Options. However, the strategy is designed so that any premiums that the Fund is obligated to pay are offset by premiums it receives in connection with the selling of FLEX Options. On the first day of the Outcome Period when the Fund enters into its other FLEX Options positions, the portfolio managers will calculate the amount of premiums that the Fund will owe and will then go into the market and sell a FLEX Option with terms that entitle the Fund to receive a premium in an amount equal to the amount that the Fund would otherwise owe. The Cap is the strike price of that sold FLEX Option. The strike price is determined based upon prevailing market conditions at the time the Fund enters into the FLEX Options, most notably current interest rate levels, S&P 500 Price Index volatility and dividend yield, and the relationship of put and calls on the underlying FLEX Options.

Buffer. The buffer that the Fund seeks to provide is only operative against the first 9% of S&P 500 Price Index losses for the Outcome Period. There is no guarantee that the Fund will be successful in its attempt to provide buffered returns. After the S&P 500 Price Index has decreased in value by more than 9%, the Fund will experience all subsequent losses on a one-to-one basis. The buffer is provided prior to taking into account annual Fund management fees equal to 0.79% of the Fund’s daily net assets, transaction fees and any extraordinary expenses incurred by the Fund. If an investor is considering purchasing Shares during the Outcome Period, and the Fund has already decreased in value by an amount equal to or greater than 9%, an investor purchasing Shares at that price will have increased gains available prior to reaching the Cap but may not benefit from the buffer that the Fund seeks to offer for the remainder of the Outcome Period. Conversely, if an investor is considering purchasing Shares during the Outcome Period, and the Fund has already increased in value, then a shareholder may experience losses prior to gaining the protection offered by the buffer. A shareholder that purchases Shares at the beginning of the Outcome Period may lose their entire investment. While the Fund seeks to limit losses to 91% for shareholders who hold Shares for the entire Outcome Period, there is no guarantee it will successfully do so. Depending upon market conditions at the time of purchase, a shareholder that purchases Shares after the Outcome Period has begun may also lose their entire investment. An investment in the Fund is only appropriate for shareholders willing to bear those losses.

Fund Rebalance. The Fund is a continuous investment vehicle. It does not terminate and distribute its assets at the conclusion of each Outcome Period. On the termination date of an Outcome Period, the Sub-Adviser will invest in a new set of FLEX Options and another Outcome Period will commence.

The Fund’s website, www.innovatoretfs.com/boct, provides information relating to the Outcomes, including the Fund’s position relative to the Cap and buffer, of an investment in the Fund on a daily basis.

The Fund is classified as “non-diversified” under the Investment Company Act of 1940, as amended (the “1940 Act”).

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund’s investment objectives will be achieved.

Active Markets Risk. Although the Shares are listed for trading on the Exchange, there can be no assurance that an active trading market for the Shares will develop or be maintained. Shares trade on the Exchange at market prices that may be below, at or above the Fund’s NAV. Securities, including the Shares, are subject to market fluctuations and liquidity constraints that may be caused by such factors as economic, political, or regulatory developments, changes in interest rates, and/or perceived trends in securities prices. Shares of the Fund could decline in value or underperform other investments.

Authorized Participation Concentration Risk. Only an authorized participant may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as authorized participants on an agency basis (i.e., on behalf of other market participants). To the extent that authorized participants exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other authorized participant is able to step forward to create or redeem “Creation Units” (as defined in “Purchase and Sale of Shares,”) Shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts and/or delisting.

Buffered Loss Risk. There can be no guarantee that the Fund will be successful in its strategy to buffer against S&P 500 Price Index losses if the S&P 500 Price Index decreases over the Outcome Period by 9% or less. A shareholder may lose their entire investment. The Fund’s strategy seeks to deliver returns that match the S&P 500 Price Index (up to the Cap), while limiting downside losses, if Shares are bought on the day on which the Fund enters into the FLEX Options and held until those FLEX Options expire at the end of each Outcome Period. In the event an investor purchases Shares after the date on which the FLEX Options were entered into or sells Shares prior to the expiration of the FLEX Options, the buffer that the Fund seeks to provide may not be available.

Cap Change Risk. A new Cap is established at the beginning of each Outcome Period and is dependent on prevailing market conditions. As such, the Cap may rise or fall from one Outcome Period to the next and is unlikely to remain the same for consecutive Outcome Periods.

Capped Upside Return Risk. The Fund’s strategy seeks to provide returns that are subject to the Cap. In the event that the S&P 500 Price Index has gains in excess of the Cap for the Outcome Period, the Fund will not participate in those gains beyond the Cap. The Fund’s strategy seeks to deliver returns that match those of the S&P 500 Price Index if Shares are bought on the day on which the Fund enters into the FLEX Options and held until those FLEX Options expire at the end of the Outcome Period. In the event an investor purchases Shares after the date on which the FLEX Options were entered into and the Fund has risen in value to a level near to the Cap, there may be little or no ability for that investor to experience an investment gain on their Shares.

Cash Transactions Risk. The Fund intends to effectuate creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an exchange-traded fund (“ETF”) that effects its creations and redemption for in-kind securities. Because the Fund will effect redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of Shares may result in capital gains or losses and may also result in higher brokerage costs. Consequently, an investment in the Fund may be less tax-efficient than investments in other ETFs. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to purchasers and redeemers of Shares in the form of creation and redemption transaction fees. In addition, these factors may result in wider spreads between the bid and the offered prices of Shares than for other ETFs.

Correlation Risk. The FLEX Options held by the Fund will be exercisable at the strike price only on their expiration date. Prior to the expiration date, the value of the FLEX Options will be determined based upon market quotations or using other recognized pricing methods. The value of the FLEX Options prior to the expiration date may vary because of related factors other than the value of the S&P 500 Price Index. Factors that may influence the value of the FLEX Options include interest rate changes and implied volatility levels of the S&P 500 Price Index, among others.

Counterparty Risk. Counterparty risk is the risk an issuer, guarantor or counterparty of a security in the Fund is unable or unwilling to meet its obligation on the security. The OCC acts as guarantor and central counterparty with respect to the FLEX Options. As a result, the ability of the Fund to meet its objective depends on the OCC being able to meet its obligations. In the unlikely event that the OCC becomes insolvent or is otherwise unable to meet its settlement obligations, the Fund could suffer significant losses.

Cyber Security Risk. As the use of Internet technology has become more prevalent in the course of business, the investment industry has become more susceptible to potential operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund’s digital information systems through “hacking” or malicious software coding, but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the Fund’s third-party service providers, such as its administrator, transfer agent, custodian, or issuers in which the Fund invests, can also subject the Fund to many of the same risks associated with direct cyber security breaches. The Fund has established risk management systems designed to reduce the risks associated with cyber security. However, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third-party service providers.

FLEX Options Risk. The Fund will utilize FLEX Options issued and guaranteed for settlement by the OCC. The Fund bears the risk that the OCC will be unable or unwilling to perform its obligations under the FLEX Options contracts. In the unlikely event that the OCC becomes insolvent or is otherwise unable to meet its settlement obligations, the Fund could suffer significant losses. Additionally, FLEX Options may be less liquid than certain other securities such as standardized options. In less liquid market for the FLEX Options, the Fund may have difficulty closing out certain FLEX Options positions at desired times and prices. The values of FLEX Options do not increase or decrease at the same rate as the reference asset and may vary due to factors other than the price of reference asset.

Fluctuation of Net Asset Value Risk. The Fund’s Shares trade on the Exchange at their market price rather than their NAV. The market price may be at, above or below the Fund’s NAV. Differences in market price and NAV may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for Shares will be closely related to, but not identical to, the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. These differences can be especially pronounced during times of market volatility or stress. During these periods, the demand for Shares may decrease considerably and cause the market price of Shares to deviate significantly from the Fund’s NAV.

Investment Objective Risk. Certain circumstances under which the Fund might not achieve its objective include, but are not limited, to (i) if the Fund disposes of FLEX Options, (ii) if the Fund is unable to maintain the proportional relationship based on the number of FLEX Options in the Fund’s portfolio, (iii) significant accrual of Fund expenses in connection with effecting the Fund’s principal investment strategy or (iv) adverse tax law changes affecting the treatment of FLEX Options.

Limitations of Intraday Indicative Value Risk. The Exchange intends to disseminate the approximate per share value of the Fund’s published basket of portfolio securities every 15 seconds (the ‘‘intraday indicative value’’ or ‘‘IIV’’). The IIV should not be viewed as a ‘‘real-time’’ update of the NAV per Share because (i) the IIV may not be calculated in the same manner as the NAV, which is computed once a day, generally at the end of the business day, (ii) the calculation of NAV may be subject to fair valuation at different prices than those used in the calculations of the IIV, (iii) unlike the calculation of NAV, the IIV does not take into account Fund expenses, and (iv) the IIV is based on the published basket of portfolio securities and not on the Fund’s actual holdings. The IIV calculations are based on local market prices and may not reflect events that occur subsequent to the local market’s close, which could affect premiums and discounts between the IIV and the market price of the Shares. The Fund, Adviser, Sub-Adviser, and their affiliates, are not involved in, or responsible for, any aspect of the calculation or dissemination of the Fund’s IIV, and the Fund, Adviser, Sub-Adviser, and their affiliates, do not make any warranty as to the accuracy of these calculations.

Liquidity Risk. In the event that trading in the underlying FLEX Options is limited or absent, the value of the Fund’s FLEX Options may decrease. There is no guarantee that a liquid secondary trading market will exist for the FLEX Options. The trading in FLEX Options may be less deep and liquid than the market for certain other securities. FLEX Options may be less liquid than certain non-customized options. In a less liquid market for the FLEX Options, terminating the FLEX Options may require the payment of a premium or acceptance of a discounted price and may take longer to complete. In a less liquid market for the FLEX Options, the liquidation of a large number of options may more significantly impact the price. A less liquid trading market may adversely impact the value of the FLEX Options and the value of your investment.

Management Risk. The Fund is subject to management risk because it is an actively managed portfolio. The Sub-Adviser will apply investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that the Fund will meet its investment objective.

Market Maker Risk. If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of Shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s NAV and the price at which the Shares are trading on the Exchange, which could result in a decrease in value of the Shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Shares trading at a discount to NAV and also in greater than normal intra-day bid-ask spreads for Shares.

Market Risk. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns. Assets may decline in value due to factors affecting financial markets generally or particular asset classes or industries represented in the markets. The value of a FLEX Options or other asset may also decline due to general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or due to factors that affect a particular issuer or issuers, country, group of countries, region, market, industry, group of industries, sector or asset class. During a general market downturn, multiple asset classes may be negatively affected. Changes in market conditions and interest rates will not have the same impact on all types of securities.

Non-Diversification Risk. The Fund is classified as “non-diversified” under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended (the “Code”). The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error in the calculation of the Cap, processing and communication errors, errors of the Fund’s service providers, counterparties or other third-parties, failed or inadequate processes and technology or systems failures. The Fund and its investment adviser and Sub-adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address these risks.

Options Risk. The value of the underlying FLEX Options will be affected by, among others, changes in the value of the S&P 500 Price Index, changes in interest rates, changes in the actual and implied volatility, as well as in dividend yields, of the S&P 500 Price Index and the remaining time to until the FLEX Options expire. The value of the FLEX Options does not increase or decrease at the same rate as the level of the S&P 500 Price Index (although they generally move in the same direction). However, as a FLEX Option approaches its expiration date, its value typically increasingly moves with the value of the S&P 500 Price Index. The Fund may experience substantial downside from specific FLEX Option positions and certain FLEX Option positions may expire worthless.

Outcome Period Risk. The Fund’s investment strategy is designed to deliver returns that match the S&P 500 Price Index if Shares are bought on the day on which the Fund enters into the FLEX Options and held until those FLEX Options expire at the end of the Outcome Period. In the event an investor purchases Shares after the date on which the FLEX Options were entered into or sells Shares prior to the expiration of the FLEX Options, the returns realized by the investor will not match those that the Fund seeks to achieve.

Tax Risk. The Fund intends to elect and to qualify each year to be treated as a regulated investment company (“RIC”) under Subchapter M of the Code. As a RIC, the Fund will not be subject to U.S. federal income tax on the portion of its net investment income and net capital gain that it distributes to unitholders, provided that it satisfies certain requirements of the Code. If the Fund does not qualify as a RIC for any taxable year and certain relief provisions are not available, the Fund’s taxable income will be subject to tax at the Fund level and to a further tax at the shareholder level when such income is distributed.

Additionally, buying securities shortly before the record date for a taxable dividend or capital gain distribution is commonly known as “buying the dividend.” In the event a shareholder purchases Shares shortly before such a distribution, the entire distribution may be taxable to the shareholder even though a portion of the distribution effectively represents a return of the purchase price.

Trading Issues Risk. Although the Shares are listed for trading on the Exchange, there can be no assurance that an active trading market for such Shares will develop or be maintained. Trading in Shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in Shares inadvisable. In addition, trading in Shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange “circuit breaker” rules. Market makers are under no obligation to make a market in the Shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. Initially, due to the small asset size of the Fund, it may have difficulty maintaining its listings on the Exchange.

Upside Participation Risk. There can be no guarantee that the Fund will be successful in its strategy to provide shareholders with a total return that matches the increase of the S&P 500 Price Index over the Outcome Period, up to the maximum return imposed by the Cap. In the event an investor purchases Shares after the date on which the FLEX Options were entered into or does not stay invested in the Fund for the entirety of the Outcome Period, the returns realized by the investor may not match those that the Fund seeks to achieve.

Valuation Risk. During periods of reduced market liquidity or in the absence of readily available market quotations for the holdings of the Fund, the ability of the Fund to value the FLEX Options becomes more difficult and the judgment of the Fund’s investment adviser (employing the fair value procedures adopted by the Board of Trustees of the Trust may play a greater role in the valuation of the Fund’s holdings due to reduced availability of reliable objective pricing data. Consequently, while such determinations may be made in good faith, it may nevertheless be more difficult for the Fund to accurately assign a daily value.

The Shares will change in value, and you could lose money by investing in the Fund. The Fund may not achieve its investment objective.

Risk Lose Money [Text]

rr_RiskLoseMoney

You could lose money by investing in the Fund.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The Fund is classified as “non-diversified” under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended (the “Code”). The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

As of the date of this prospectus, the Fund has not commenced operations and therefore does not have a performance history. Once available, the Fund’s performance information will be accessible on the Fund’s website at www.innovatoretfs.com and will provide some indication of the risks of investing in the Fund.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

Once available, the Fund’s performance information will be accessible on the Fund’s website at www.innovatoretfs.com and will provide some indication of the risks of investing in the Fund.

Performance One Year or Less [Text]

rr_PerformanceOneYearOrLess

As of the date of this prospectus, the Fund has not commenced operations and therefore does not have a performance history.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.innovatoretfs.com

Innovator S&P 500 Buffer ETF - October | Innovator S&P 500 Buffer ETF - October

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.79%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

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none

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.79%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 80

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

$ 251

[1] "Other Expenses" are estimates based on the expenses the Fund expects to incur for the current fiscal year.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Prospectus Date	rr_ProspectusDate	Oct. 01, 2018