Label

Element

Value

Risk/Return:

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Registrant Name

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FIDELITY SALEM STREET TRUST

Prospectus Date

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Oct. 30, 2014

Inst Adv Inst | Spartan U.S. Bond Index Fund

Risk/Return:

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Supplement [Text Block]

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Supplement to the
Spartan^® U.S. Bond Index Fund
Institutional Class and Fidelity Advantage^® Institutional Class
October 30, 2014
Prospectus

The following information replaces similar information found in the "Fund Summary" section under the heading "Fee Table" on page 3.

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

	Institutional Class	Fidelity Advantage® Institutional Class
Management fee	0.05%	0.05%
Distribution and/or Service (12b-1) fees	None	None
Other expenses	0.02%	0.00%
Total annual operating expenses	0.07%	0.05%
Fee waiver and/or expense reimbursementA	0.01%	0.00%
Total annual operating expenses after fee waiver and/or expense reimbursement	0.06%	0.05%

^A Fidelity Management & Research Company (FMR) has contractually agreed to reimburse Institutional Class and Fidelity Advantage Institutional Class of the fund to the extent that total operating expenses (excluding interest, certain taxes, certain securities lending costs, brokerage commissions, extraordinary expenses, and acquired fund fees and expenses, if any), as a percentage of its average net assets, exceed 0.06% and 0.05%, respectively. These arrangements will remain in effect through October 31, 2016. FMR may not terminate these arrangements before the expiration date without the approval of the Board of Trustees.

The following information replaces similar information found in the "Fund Summary" section under the heading "Fee Table" on page 4.

	Institutional Class	Fidelity Advantage Institutional Class
1 year	$ 6	$ 5
3 years	$ 20	$ 16
5 years	$ 37	$ 28
10 years	$ 88	$ 64