497

August 7, 2017

James E. O’Connor, Esquire
Division of Investment Management
U.S. Securities & Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549

Re:T. Rowe Price Index Trust, Inc. (“Registrant”)

Dear Mr. O’Connor:

In accordance with the provisions of Rule 497 of the Securities Act of 1933, we are hereby filing the above-captioned sticker.

The information contained in these eXtensible Business Reporting Language (“XBRL”) exhibits relates to the prospectus sticker filed under Rule 497 on July 26, 2017.

Please contact me at 410-345-6628, or in my absence, Brian R. Poole at 410-345-6646, if we may be of further assistance.

Sincerely,

/s/Gina Hogan
Gina Hogan

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Document Type	dei_DocumentType	497
Document Period End Date	dei_DocumentPeriodEndDate	Dec. 31, 2016
Registrant Name	dei_EntityRegistrantName	T. Rowe Price Index Trust, Inc.
Central Index Key	dei_EntityCentralIndexKey	0000858581
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Jul. 26, 2017
Document Effective Date	dei_DocumentEffectiveDate	Jul. 26, 2017
Prospectus Date	rr_ProspectusDate	May 01, 2017

XML

May 01, 2017

T. Rowe Price Equity Index 500 Fund

Supplement to Prospectus Dated May 1, 2017

The fund’s Board of Directors approved lowering the fund’s management fee from 0.10% to 0.06%, and lowering the current limitation in the Investor Class’ total expense ratio from 0.25% to 0.21%, effective August 1, 2017. On pages 1-2, the fee table and expense example are revised as follows, effective August 1, 2017, to reflect the reduction of the management fee and Investor Class’ expense limitation:

Fees and Expenses of the Fund

	Investor Class		I Class
Shareholder fees (fees paid directly from your investment)
Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)	0.50	%	0.50%
Maximum account fee	$20	a	—
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
Management fees	0.06	%b	0.06	%b
Distribution and service (12b-1) fees	—		—
Other expenses	0.17		—
Total annual fund operating expenses	0.23	b	0.06	b
Fee waiver/expense reimbursement	(0.02	)b,c	—
Total annual fund operating expenses after fee waiver/expense reimbursement	0.21	b,c	0.06	b

a Subject to certain exceptions, accounts with a balance of less than $10,000 are charged an annual $20 fee.

b Restated to reflect current fees.

c T. Rowe Price Associates, Inc., has agreed (through April 30, 2020) to waive its fees and/or bear any expenses (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses) that would cause the class’ ratio of expenses to average daily net assets to exceed 0.21%. The agreement may be terminated at any time beyond April 30, 2020, with approval by the fund’s Board of Directors. Fees waived and expenses paid under this agreement (and previous limitations of 0.25% and 0.30%) are subject to reimbursement to T. Rowe Price Associates, Inc., by the fund whenever the class’ expense ratio is below 0.21%. However, no reimbursement will be made more than three years after the waiver or payment, or if it would result in the expense ratio exceeding 0.21% (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses).

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, that your investment has a 5% return each year, and that the fund’s operating expenses remain the same. The example also assumes that an expense limitation currently in place is not renewed; therefore, the figures have been adjusted to reflect fee waivers or expense reimbursements only in the periods for which the expense limitation arrangement is expected to continue. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 year	3 years	5 years	10 years
Investor Class	$22	$68	$124	$287
I Class	6	19	34	77

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

T. Rowe Price Index Trust, Inc.

Prospectus Date

rr_ProspectusDate

May 01, 2017

Supplement [Text Block]

trpiti_SupplementTextBlock

T. Rowe Price Equity Index 500 Fund

Supplement to Prospectus Dated May 1, 2017

The fund’s Board of Directors approved lowering the fund’s management fee from 0.10% to 0.06%, and lowering the current limitation in the Investor Class’ total expense ratio from 0.25% to 0.21%, effective August 1, 2017. On pages 1-2, the fee table and expense example are revised as follows, effective August 1, 2017, to reflect the reduction of the management fee and Investor Class’ expense limitation:

Fees and Expenses of the Fund

	Investor Class		I Class
Shareholder fees (fees paid directly from your investment)
Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)	0.50	%	0.50%
Maximum account fee	$20	a	—
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
Management fees	0.06	%b	0.06	%b
Distribution and service (12b-1) fees	—		—
Other expenses	0.17		—
Total annual fund operating expenses	0.23	b	0.06	b
Fee waiver/expense reimbursement	(0.02	)b,c	—
Total annual fund operating expenses after fee waiver/expense reimbursement	0.21	b,c	0.06	b

a Subject to certain exceptions, accounts with a balance of less than $10,000 are charged an annual $20 fee.

b Restated to reflect current fees.

c T. Rowe Price Associates, Inc., has agreed (through April 30, 2020) to waive its fees and/or bear any expenses (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses) that would cause the class’ ratio of expenses to average daily net assets to exceed 0.21%. The agreement may be terminated at any time beyond April 30, 2020, with approval by the fund’s Board of Directors. Fees waived and expenses paid under this agreement (and previous limitations of 0.25% and 0.30%) are subject to reimbursement to T. Rowe Price Associates, Inc., by the fund whenever the class’ expense ratio is below 0.21%. However, no reimbursement will be made more than three years after the waiver or payment, or if it would result in the expense ratio exceeding 0.21% (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses).

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, that your investment has a 5% return each year, and that the fund’s operating expenses remain the same. The example also assumes that an expense limitation currently in place is not renewed; therefore, the figures have been adjusted to reflect fee waivers or expense reimbursements only in the periods for which the expense limitation arrangement is expected to continue. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 year	3 years	5 years	10 years
Investor Class	$22	$68	$124	$287
I Class	6	19	34	77

T. Rowe Price Equity Index 500 Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

trpiti_SupplementTextBlock

T. Rowe Price Equity Index 500 Fund

Supplement to Prospectus Dated May 1, 2017

The fund’s Board of Directors approved lowering the fund’s management fee from 0.10% to 0.06%, and lowering the current limitation in the Investor Class’ total expense ratio from 0.25% to 0.21%, effective August 1, 2017. On pages 1-2, the fee table and expense example are revised as follows, effective August 1, 2017, to reflect the reduction of the management fee and Investor Class’ expense limitation:

Fees and Expenses of the Fund

	Investor Class		I Class
Shareholder fees (fees paid directly from your investment)
Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)	0.50	%	0.50%
Maximum account fee	$20	a	—
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
Management fees	0.06	%b	0.06	%b
Distribution and service (12b-1) fees	—		—
Other expenses	0.17		—
Total annual fund operating expenses	0.23	b	0.06	b
Fee waiver/expense reimbursement	(0.02	)b,c	—
Total annual fund operating expenses after fee waiver/expense reimbursement	0.21	b,c	0.06	b

a Subject to certain exceptions, accounts with a balance of less than $10,000 are charged an annual $20 fee.

b Restated to reflect current fees.

c T. Rowe Price Associates, Inc., has agreed (through April 30, 2020) to waive its fees and/or bear any expenses (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses) that would cause the class’ ratio of expenses to average daily net assets to exceed 0.21%. The agreement may be terminated at any time beyond April 30, 2020, with approval by the fund’s Board of Directors. Fees waived and expenses paid under this agreement (and previous limitations of 0.25% and 0.30%) are subject to reimbursement to T. Rowe Price Associates, Inc., by the fund whenever the class’ expense ratio is below 0.21%. However, no reimbursement will be made more than three years after the waiver or payment, or if it would result in the expense ratio exceeding 0.21% (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses).

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, that your investment has a 5% return each year, and that the fund’s operating expenses remain the same. The example also assumes that an expense limitation currently in place is not renewed; therefore, the figures have been adjusted to reflect fee waivers or expense reimbursements only in the periods for which the expense limitation arrangement is expected to continue. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 year	3 years	5 years	10 years
Investor Class	$22	$68	$124	$287
I Class	6	19	34	77

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Fees and Expenses of the Fund

Shareholder fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual fund operating expenses
(expenses that you pay each year as a
percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

April 30, 2020

Expenses Restated to Reflect Current [Text]

rr_ExpensesRestatedToReflectCurrent

Restated to reflect current fees.

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

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, that your investment has a 5% return each year, and that the fund’s operating expenses remain the same. The example also assumes that an expense limitation currently in place is not renewed; therefore, the figures have been adjusted to reflect fee waivers or expense reimbursements only in the periods for which the expense limitation arrangement is expected to continue. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

T. Rowe Price Equity Index 500 Fund | Investor Class

Risk/Return:

rr_RiskReturnAbstract

Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)

rr_RedemptionFeeOverRedemption

0.50%

Maximum account fee

rr_MaximumAccountFee

$ 20

^[1]

Management fees

rr_ManagementFeesOverAssets

0.06%

^[2]

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

Other expenses

rr_OtherExpensesOverAssets

0.17%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.23%

^[2]

Fee waiver/expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.02%)

^[2],[3]

Total annual fund operating expenses after fee waiver/expense reimbursement

rr_NetExpensesOverAssets

0.21%

^[2],[3]

1 year

rr_ExpenseExampleYear01

$ 22

3 years

rr_ExpenseExampleYear03

68

5 years

rr_ExpenseExampleYear05

124

10 years

rr_ExpenseExampleYear10

$ 287

T. Rowe Price Equity Index 500 Fund | I Class

Risk/Return:

rr_RiskReturnAbstract

Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)

rr_RedemptionFeeOverRedemption

0.50%

Maximum account fee

rr_MaximumAccountFee

Management fees

rr_ManagementFeesOverAssets

0.06%

^[2]

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

Other expenses

rr_OtherExpensesOverAssets

Total annual fund operating expenses

rr_ExpensesOverAssets

0.06%

^[2]

Fee waiver/expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

Total annual fund operating expenses after fee waiver/expense reimbursement

rr_NetExpensesOverAssets

0.06%

^[2]

1 year

rr_ExpenseExampleYear01

$ 6

3 years

rr_ExpenseExampleYear03

19

5 years

rr_ExpenseExampleYear05

34

10 years

rr_ExpenseExampleYear10

$ 77

[1] Subject to certain exceptions, accounts with a balance of less than $10,000 are charged an annual $20 fee.

[2] Restated to reflect current fees.

[3] T. Rowe Price Associates, Inc., has agreed (through April 30, 2020) to waive its fees and/or bear any expenses (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses) that would cause the class’ ratio of expenses to average daily net assets to exceed 0.21%. The agreement may be terminated at any time beyond April 30, 2020, with approval by the fund’s Board of Directors. Fees waived and expenses paid under this agreement (and previous limitations of 0.25% and 0.30%) are subject to reimbursement to T. Rowe Price Associates, Inc., by the fund whenever the class’ expense ratio is below 0.21%. However, no reimbursement will be made more than three years after the waiver or payment, or if it would result in the expense ratio exceeding 0.21% (excluding interest; expenses related to borrowings, taxes, and brokerage; nonrecurring, extraordinary expenses; and acquired fund fees and expenses).

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	T. Rowe Price Index Trust, Inc.
Prospectus Date	rr_ProspectusDate	May 01, 2017
Document Creation Date	dei_DocumentCreationDate	Jul. 26, 2017