497

Eaton Vance Management

Two International Place

Boston, MA  02110

(617)482-8260

www.eatonvance.com

January 3, 2013

Securities and Exchange Commission

100 F Street, NE  

Washington, DC  20549

Attn:  Office of Filings, Information & Consumer Services

Re:

Eaton Vance Special Investment Trust (the “Registrant”) (1933 Act File No. 002-90946)

on behalf of Eaton Vance Parametric Option Absolute Return Strategy (the “Fund”)

Ladies and Gentlemen:

On behalf of the Registrant and pursuant to Rule 497(e) under the Securities Act of 1933, as amended, attached for filing are exhibits containing interactive data format risk/return summary information that mirrors the risk/return summary information in a supplement dated December 13, 2012 to the Prospectus dated May 1, 2012 of the Fund.  The purpose of the filing is to submit the 497(e) filing dated December 13, 2012 in XBRL for the Fund.

If you have any questions concerning the foregoing, kindly call the undersigned at (617) 672-8055.

Very truly yours,

/s/ Deanna Foley

Deanna Foley

Paralegal

XML

Eaton Vance Parametric Option Absolute Return Strategy Fund

EATON VANCE PARAMETRIC OPTION ABSOLUTE RETURN STRATEGY FUND
Supplement to Prospectus dated May 1, 2012

The following replaces “Fees and Expenses of the Fund” under “Fund Summaries – Eaton Vance Parametric Option Absolute Return Strategy Fund”:

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund.  You may qualify for a reduced sales charge if you invest, or agree to invest over a 13-month period, at least $50,000 in Eaton Vance Funds.  More information about these and other discounts is available from your financial intermediary and in Sales Charges beginning on page 25 of the Fund's Prospectus and page 21 of the Fund’s Statement of Additional Information.  

Shareholder Fees (fees paid directly from your investment)	Class A	Class C	Class I
Maximum Sales Charge (Load) (as a percentage of offering price)	4.75%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at time of purchase or redemption)	None	1.00%	None

Annual Fund Operating Expenses (expenses you pay each year as a percentage of the value of your investment)	Class A	Class C	Class I
Management Fees	1.10%	1.10%	1.10%
Distribution and Service (12b-1) Fees	0.25%	1.00%	n/a
Other Expenses	0.45%	0.45%	0.45%
Total Annual Fund Operating Expenses	1.80%	2.55%	1.55%
Expense Reimbursement (1)	(0.35)%	(0.35)%	(0.35)%
Total Annual Fund Operating Expenses After Expense Reimbursement	1.45%	2.20%	1.20%

⁽¹⁾

The investment adviser, sub-adviser and administrator have agreed to reimburse the Fund’s expenses to the extent that Total Annual Fund Operating Expenses exceed 1.45% for Class A shares, 2.20% for Class C shares and 1.20% for Class I shares.  This expense reimbursement will continue through April 30, 2013.  Any amendment to or a termination of this reimbursement would require written approval of the Board of Trustees.  The expense reimbursement relates to ordinary operating expenses only and does not include expenses such as: brokerage commissions, acquired fund fees and expenses, interest expense, taxes or litigation expenses.  Amounts reimbursed may be recouped by the investment adviser, sub-adviser and administrator during the Fund’s current fiscal year to the extent actual expenses are less than the contractual expense cap during such year.

Example.  This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.  The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem 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 operating expenses remain the same.  Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	Expenses with Redemption				Expenses without Redemption
	1 Year	3 Years	5 Years	10 Years	1 Year	3 Years	5 Years	10 Years
Class A shares	$616	$982	$1,372	$2,463	$616	$982	$1,372	$2,463
Class C shares	$323	$760	$1,324	$2,859	$223	$760	$1,324	$2,859
Class I shares	$122	$455	$812	$1,816	$122	$455	$812	$1,816

December 13, 2012 6503-12/12   PPAOARCOMMPS

Shareholder Fees Eaton Vance Parametric Option Absolute Return Strategy Fund	Class A	Class C	Class I
Maximum Sales Charge (Load) (as a percentage of offering price)	4.75%	none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at purchase or redemption)	none	1.00%	none

Annual Fund Operating Expenses Eaton Vance Parametric Option Absolute Return Strategy Fund		Class A	Class C	Class I
Management Fees		1.10%	1.10%	1.10%
Distribution and Service (12b-1) Fees		0.25%	1.00%	none
Other Expenses		0.45%	0.45%	0.45%
Acquired Fund Fees and Expenses		1.80%	2.55%	1.55%
Expense Reimbursement	[1]	(0.35%)	(0.35%)	(0.35%)
Total Annual Fund Operating Expenses After Expense Reimbursement		1.45%	2.20%	1.20%

Expense Example Eaton Vance Parametric Option Absolute Return Strategy Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Class A	616	982	1,372	2,463
Class C	323	760	1,324	2,859
Class I	122	455	812	1,816

Expense Example, No Redemption Eaton Vance Parametric Option Absolute Return Strategy Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Class A	616	982	1,372	2,463
Class C	223	760	1,324	2,859
Class I	122	455	812	1,816

[1] The investment adviser, sub-adviser and administrator have agreed to reimburse the Fund's expenses to the extent that Total Annual Fund Operating Expenses exceed 1.45% for Class A shares, 2.20% for Class C shares and 1.20% for Class I shares. This expense reimbursement will continue through April 30, 2013. Any amendment to or a termination of this reimbursement would require written approval of the Board of Trustees. The expense reimbursement relates to ordinary operating expenses only and does not include expenses such as: brokerage commissions, acquired fund fees and expenses, interest expense, taxes or litigation expenses. Amounts reimbursed may be recouped by the investment adviser, sub-adviser and administrator during the Fund's current fiscal year to the extent actual expenses are less than the contractual expense cap during such year.

XML

Label

Element

Value

[RiskReturnAbstract]

rr_RiskReturnAbstract

Document Type

dei_DocumentType

Other

Document Period End Date

dei_DocumentPeriodEndDate

Dec. 31, 2011

Registrant Name

dei_EntityRegistrantName

Eaton Vance Special Investment Trust

Central Index Key

dei_EntityCentralIndexKey

0000031266

Amendment Flag

dei_AmendmentFlag

false

Document Creation Date

dei_DocumentCreationDate

Dec. 13, 2012

Document Effective Date

dei_DocumentEffectiveDate

Dec. 13, 2012

Prospectus Date

rr_ProspectusDate

May 01, 2012

Eaton Vance Parametric Option Absolute Return Strategy Fund

[RiskReturnAbstract]

rr_RiskReturnAbstract

Supplement [Text Block]

EVSIT_SupplementTextBlock

EATON VANCE PARAMETRIC OPTION ABSOLUTE RETURN STRATEGY FUND
Supplement to Prospectus dated May 1, 2012

The following replaces “Fees and Expenses of the Fund” under “Fund Summaries – Eaton Vance Parametric Option Absolute Return Strategy Fund”:

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund.  You may qualify for a reduced sales charge if you invest, or agree to invest over a 13-month period, at least $50,000 in Eaton Vance Funds.  More information about these and other discounts is available from your financial intermediary and in Sales Charges beginning on page 25 of the Fund's Prospectus and page 21 of the Fund’s Statement of Additional Information.  

Shareholder Fees (fees paid directly from your investment)	Class A	Class C	Class I
Maximum Sales Charge (Load) (as a percentage of offering price)	4.75%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at time of purchase or redemption)	None	1.00%	None

Annual Fund Operating Expenses (expenses you pay each year as a percentage of the value of your investment)	Class A	Class C	Class I
Management Fees	1.10%	1.10%	1.10%
Distribution and Service (12b-1) Fees	0.25%	1.00%	n/a
Other Expenses	0.45%	0.45%	0.45%
Total Annual Fund Operating Expenses	1.80%	2.55%	1.55%
Expense Reimbursement (1)	(0.35)%	(0.35)%	(0.35)%
Total Annual Fund Operating Expenses After Expense Reimbursement	1.45%	2.20%	1.20%

⁽¹⁾

The investment adviser, sub-adviser and administrator have agreed to reimburse the Fund’s expenses to the extent that Total Annual Fund Operating Expenses exceed 1.45% for Class A shares, 2.20% for Class C shares and 1.20% for Class I shares.  This expense reimbursement will continue through April 30, 2013.  Any amendment to or a termination of this reimbursement would require written approval of the Board of Trustees.  The expense reimbursement relates to ordinary operating expenses only and does not include expenses such as: brokerage commissions, acquired fund fees and expenses, interest expense, taxes or litigation expenses.  Amounts reimbursed may be recouped by the investment adviser, sub-adviser and administrator during the Fund’s current fiscal year to the extent actual expenses are less than the contractual expense cap during such year.

Example.  This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.  The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem 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 operating expenses remain the same.  Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	Expenses with Redemption				Expenses without Redemption
	1 Year	3 Years	5 Years	10 Years	1 Year	3 Years	5 Years	10 Years
Class A shares	$616	$982	$1,372	$2,463	$616	$982	$1,372	$2,463
Class C shares	$323	$760	$1,324	$2,859	$223	$760	$1,324	$2,859
Class I shares	$122	$455	$812	$1,816	$122	$455	$812	$1,816

December 13, 2012 6503-12/12   PPAOARCOMMPS

Eaton Vance Parametric Option Absolute Return Strategy Fund | Class A

[RiskReturnAbstract]

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

EOAAX

Maximum Sales Charge (Load) (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

4.75%

Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at purchase or redemption)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

1.10%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.45%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

1.80%

Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.35%)

^[1]

Total Annual Fund Operating Expenses After Expense Reimbursement

rr_NetExpensesOverAssets

1.45%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

616

3 Years

rr_ExpenseExampleYear03

982

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,372

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,463

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

616

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

982

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,372

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,463

Eaton Vance Parametric Option Absolute Return Strategy Fund | Class C

[RiskReturnAbstract]

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

EOACX

Maximum Sales Charge (Load) (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at purchase or redemption)

rr_MaximumDeferredSalesChargeOverOther

1.00%

Management Fees

rr_ManagementFeesOverAssets

1.10%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.45%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

2.55%

Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.35%)

^[1]

Total Annual Fund Operating Expenses After Expense Reimbursement

rr_NetExpensesOverAssets

2.20%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

323

3 Years

rr_ExpenseExampleYear03

760

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,324

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,859

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

223

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

760

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,324

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,859

Eaton Vance Parametric Option Absolute Return Strategy Fund | Class I

[RiskReturnAbstract]

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

EOAIX

Maximum Sales Charge (Load) (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at purchase or redemption)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

1.10%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.45%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

1.55%

Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.35%)

^[1]

Total Annual Fund Operating Expenses After Expense Reimbursement

rr_NetExpensesOverAssets

1.20%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

122

3 Years

rr_ExpenseExampleYear03

455

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

812

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,816

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

122

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

455

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

812

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

1,816

[1] The investment adviser, sub-adviser and administrator have agreed to reimburse the Fund's expenses to the extent that Total Annual Fund Operating Expenses exceed 1.45% for Class A shares, 2.20% for Class C shares and 1.20% for Class I shares. This expense reimbursement will continue through April 30, 2013. Any amendment to or a termination of this reimbursement would require written approval of the Board of Trustees. The expense reimbursement relates to ordinary operating expenses only and does not include expenses such as: brokerage commissions, acquired fund fees and expenses, interest expense, taxes or litigation expenses. Amounts reimbursed may be recouped by the investment adviser, sub-adviser and administrator during the Fund's current fiscal year to the extent actual expenses are less than the contractual expense cap during such year.

XML

Eaton Vance Parametric Option Absolute Return Strategy Fund

EATON VANCE PARAMETRIC OPTION ABSOLUTE RETURN STRATEGY FUND
Supplement to Prospectus dated May 1, 2012

The following replaces “Fees and Expenses of the Fund” under “Fund Summaries – Eaton Vance Parametric Option Absolute Return Strategy Fund”:

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund.  You may qualify for a reduced sales charge if you invest, or agree to invest over a 13-month period, at least $50,000 in Eaton Vance Funds.  More information about these and other discounts is available from your financial intermediary and in Sales Charges beginning on page 25 of the Fund's Prospectus and page 21 of the Fund’s Statement of Additional Information.  

Shareholder Fees (fees paid directly from your investment)	Class A	Class C	Class I
Maximum Sales Charge (Load) (as a percentage of offering price)	4.75%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at time of purchase or redemption)	None	1.00%	None

Annual Fund Operating Expenses (expenses you pay each year as a percentage of the value of your investment)	Class A	Class C	Class I
Management Fees	1.10%	1.10%	1.10%
Distribution and Service (12b-1) Fees	0.25%	1.00%	n/a
Other Expenses	0.45%	0.45%	0.45%
Total Annual Fund Operating Expenses	1.80%	2.55%	1.55%
Expense Reimbursement (1)	(0.35)%	(0.35)%	(0.35)%
Total Annual Fund Operating Expenses After Expense Reimbursement	1.45%	2.20%	1.20%

⁽¹⁾

The investment adviser, sub-adviser and administrator have agreed to reimburse the Fund’s expenses to the extent that Total Annual Fund Operating Expenses exceed 1.45% for Class A shares, 2.20% for Class C shares and 1.20% for Class I shares.  This expense reimbursement will continue through April 30, 2013.  Any amendment to or a termination of this reimbursement would require written approval of the Board of Trustees.  The expense reimbursement relates to ordinary operating expenses only and does not include expenses such as: brokerage commissions, acquired fund fees and expenses, interest expense, taxes or litigation expenses.  Amounts reimbursed may be recouped by the investment adviser, sub-adviser and administrator during the Fund’s current fiscal year to the extent actual expenses are less than the contractual expense cap during such year.

Example.  This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.  The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem 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 operating expenses remain the same.  Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	Expenses with Redemption				Expenses without Redemption
	1 Year	3 Years	5 Years	10 Years	1 Year	3 Years	5 Years	10 Years
Class A shares	$616	$982	$1,372	$2,463	$616	$982	$1,372	$2,463
Class C shares	$323	$760	$1,324	$2,859	$223	$760	$1,324	$2,859
Class I shares	$122	$455	$812	$1,816	$122	$455	$812	$1,816

December 13, 2012 6503-12/12   PPAOARCOMMPS

Shareholder Fees Eaton Vance Parametric Option Absolute Return Strategy Fund	Class A	Class C	Class I
Maximum Sales Charge (Load) (as a percentage of offering price)	4.75%	none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of net asset value at purchase or redemption)	none	1.00%	none

Annual Fund Operating Expenses Eaton Vance Parametric Option Absolute Return Strategy Fund		Class A	Class C	Class I
Management Fees		1.10%	1.10%	1.10%
Distribution and Service (12b-1) Fees		0.25%	1.00%	none
Other Expenses		0.45%	0.45%	0.45%
Acquired Fund Fees and Expenses		1.80%	2.55%	1.55%
Expense Reimbursement	[1]	(0.35%)	(0.35%)	(0.35%)
Total Annual Fund Operating Expenses After Expense Reimbursement		1.45%	2.20%	1.20%

Expense Example Eaton Vance Parametric Option Absolute Return Strategy Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Class A	616	982	1,372	2,463
Class C	323	760	1,324	2,859
Class I	122	455	812	1,816

Expense Example, No Redemption Eaton Vance Parametric Option Absolute Return Strategy Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Class A	616	982	1,372	2,463
Class C	223	760	1,324	2,859
Class I	122	455	812	1,816

[1] The investment adviser, sub-adviser and administrator have agreed to reimburse the Fund's expenses to the extent that Total Annual Fund Operating Expenses exceed 1.45% for Class A shares, 2.20% for Class C shares and 1.20% for Class I shares. This expense reimbursement will continue through April 30, 2013. Any amendment to or a termination of this reimbursement would require written approval of the Board of Trustees. The expense reimbursement relates to ordinary operating expenses only and does not include expenses such as: brokerage commissions, acquired fund fees and expenses, interest expense, taxes or litigation expenses. Amounts reimbursed may be recouped by the investment adviser, sub-adviser and administrator during the Fund's current fiscal year to the extent actual expenses are less than the contractual expense cap during such year.