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</b>
<h1 align="left"><a name="fid80676"> </a>Fund Summary</h1>
<p align="left"> </p>Fund/Class:<br /><b>Spartan</b><sup>®</sup><b> U.S. Bond Index Fund</b>/Institutional, Fidelity Advantage Institutional
<p> </p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 2
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<h3 align="left">Investment Objective</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1
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-Name Form
-Number N-1A
-Chapter A
-Section 2
-Subsection a
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<p align="left">The fund seeks to provide investment results that correspond to the aggregate price and interest performance of the debt securities in the Barclays Capital<sup>®</sup> U.S. Aggregate Bond Index. </p></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 2
-Subsection a
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<h3 align="left">Fee Table</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph d
-Subsection instructions
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<p style="margin-top: 0px; margin-bottom: 0px;" align="left">The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.</p></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph b
-Subsection instructions
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<p style="margin-top: 0px; margin-bottom: 0px;" align="left"><b>Shareholder fees</b></p>
<p style="margin-top: 0px; margin-bottom: 0px;" align="left"><b><font class="_mt" size="-2">(fees paid directly from your investment)</font></b> </p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringShareholder Fees (fees paid directly from your investment).Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subsection table
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-Publisher SEC
-Name Form
-Number N-1A
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Adv
Spartan U.S. Bond Index Fund
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<p align="left"><b>Annual class operating expenses<br /><font class="_mt" size="-2">(expenses that you pay each year as a % of the value of your investment)</font></b> </p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 3
-Subparagraph a
-Subsection instructions
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph 9
-Subsection table
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
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Adv
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<p align="left">This <b>example</b> helps compare the cost of investing in the fund with the cost of investing in other mutual funds. </p>
<p align="left">Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated: </p></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph 1
-Subsection example
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 4
-Subsection instructions
falsefalseUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear01truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue77falsefalsefalsetruefalse2truefalsetrue55falsefalsefalsetruefalseOthernanafalsefalse2falseRowprimaryElement*RowunitUnit*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue2323falsefalsefalsetruefalse2truefalsetrue1616falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph 2
-Subsection example
falsefalseUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear03truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue2323falsefalsefalsetruefalse2truefalsetrue1616falsefalsefalsetruefalseOthernanafalsefalse3falseRowprimaryElement*RowunitUnit*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue4040falsefalsefalsetruefalse2truefalsetrue2828falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
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-Section 3
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-Subparagraph 2
-Subsection example
falsefalseUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear05truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue4040falsefalsefalsetruefalse2truefalsetrue2828falsefalsefalsetruefalseOthernanafalsefalse4falseRowprimaryElement*RowunitUnit*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue9090falsefalsefalsetruefalse2truefalsetrue6464falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
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-Section 3
-Paragraph 1
-Subparagraph 2
-Subsection example
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Adv
Spartan U.S. Bond Index Fund
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<h3 align="left">Portfolio Turnover</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1
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<p align="left">The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was <font class="_mt">165%</font> of the average value of its portfolio. </p></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 3
-Subsection example
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<h3 align="left">Principal Investment Strategies</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection a
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<ul>
<li>Normally investing at least 80% of the fund's assets in bonds included in the Barclays Capital<sup>®</sup> U.S. Aggregate Bond Index (the Index).
</li>
<li>Using statistical sampling techniques based on duration, maturity, interest rate sensitivity, security structure, and credit quality to attempt to replicate the returns of the Index using a smaller number of securities.
</li>
<li>Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default) and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
</li>
<li>Investing in Fidelity's central funds (specialized investment vehicles used by Fidelity funds to invest in particular security types or investment disciplines). </li></ul></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection a
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<h3 align="left">Principal Investment Risks</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1
-Publisher SEC
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-Subsection b
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<ul>
<li><i>Interest Rate Changes.</i> Interest rate increases can cause the price of a debt security to decrease.
</li>
<li><i>Foreign Exposure.</i> Entities located in foreign countries can be affected by adverse political, regulatory, market, or economic developments in those countries.
</li>
<li><i>Prepayment.</i> The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
</li>
<li><i>Issuer-Specific Changes.</i> The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support or a maturity-shortening structure for a security can cause the price of a security to decrease.
</li>
<li><i>Leverage Risk.</i> Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. </li></ul>
<p align="left"><font class="_mt">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 government agency. </font>Unlike individual debt securities, which typically pay principal at maturity, the value of an investment in the fund will fluctuate. <font class="_mt">You could lose money by investing in the fund.</font> </p></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 1
-Subparagraph i
-Clause instruction
-Subsection b
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<h3 align="left">Performance</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1
-Publisher SEC
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-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
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<p align="left"><font class="_mt">The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time. </font>The index description appears in the Additional Information about the Index section of the prospectus. <font class="_mt">Past performance (before and after taxes) is not an indication of future performance.</font> </p>
<p align="left">Visit <font class="_mt">www.401k.com</font> (log in, choose plan, select Investment Choices & Research, and then pick investment option) for updated return information. </p>
<div class="MetaData">
<p align="left">Performance history will be available for Institutional Class and Fidelity Advantage Institutional Class after Institutional Class and Fidelity Advantage Institutional Class have been in operation for one calendar year. </p></div></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
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-Section 4
-Paragraph 2
-Subsection b
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<p style="line-height: normal; margin: 0in 0in 10pt;" class="MsoNormal"><font class="_mt"><strong>Year-by-Year Returns</strong><sup>[1]</sup></font>
</p>
<div>
<p style="line-height: normal; margin: 0in 0in 10pt;" class="MsoNormal"><strong><font size="3" class="_mt"> </font></strong></p></div>
<p> </p><font size="1" class="_mt">Calendar Years</font>
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-Publisher SEC
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-Number N-1A
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph instructions
-Clause 3
-Exhibit a
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph instructions
-Clause 3
-Exhibit a
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph instructions
-Clause 3
-Exhibit a
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph instructions
-Clause 3
-Exhibit a
-Subsection b
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-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*ColumnprimaryElement*ColumnunitUnit*Rowdei_DocumentInformationDocumentAxisAxiscik000035315_AdvMemberRowdei_LegalEntityAxisAxiscik000035315_S000017676MemberRowrr_ProspectusShareClassAxisAxis*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalse24false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData">
<table border="1" width="95%">
<tr><td valign="bottom" align="left">
<p align="left"><i><font class="_mt" size="-1">During the periods shown in the chart:</font></i> </p></td>
<td valign="bottom" align="center">
<p align="center"><i><font class="_mt" size="-2">Returns</font></i> </p></td>
<td valign="bottom" align="center">
<p align="center"><i><font class="_mt" size="-2">Quarter ended</font></i> </p></td></tr>
<tr><td valign="bottom" align="left">
<p align="left"><i><font class="_mt" size="-1">Highest Quarter Return</font></i> </p></td>
<td valign="bottom" align="left">
<p align="center"><i><font class="_mt" size="-1">4.86%</font></i> </p></td>
<td valign="bottom" align="left">
<p align="center"><i><font class="_mt" size="-1">September 30, 2001</font></i> </p></td></tr>
<tr><td valign="bottom" align="left">
<p align="left"><i><font class="_mt" size="-1">Lowest Quarter Return</font></i> </p></td>
<td valign="bottom" align="left">
<p align="center"><i><font class="_mt" size="-1">-2.56%</font></i> </p></td>
<td valign="bottom" align="left">
<p align="center"><i><font class="_mt" size="-1">June 30, 2004</font></i> </p></td></tr>
<tr><td valign="top" align="left">
<p align="left"><i><font class="_mt" size="-1">Year to Date Return</font></i> </p></td>
<td valign="top" align="left">
<p align="center"><i><font class="_mt" size="-1">0.30%</font></i> </p></td>
<td valign="top" align="left">
<p align="center"><i><font class="_mt" size="-1">March 31, 2011</font></i> </p></td></tr></table></div> </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
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-Section 4
-Paragraph 2
-Subparagraph ii
-Subsection b
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<p style="margin-top: 0px; margin-bottom: 0px;" align="left"><b>Average Annual Returns</b> </p>
<p style="margin-top: 0px; margin-bottom: 0px;" align="left"><font size="1" class="_mt">For the periods ended<br />December 31, 2010</font></p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
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-Paragraph 2
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-Clause 3
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-Publisher SEC
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The returns shown above are for Investor Class, a class of shares of the fund that is not offered through this prospectus. Institutional Class and Fidelity Advantage Institutional Class would have substantially similar annual returns to Investor Class because the classes are invested in the same portfolio of securities. Institutional Class's and Fidelity Advantage Institutional Class's returns would differ from Investor Class's returns to the extent that the classes do not have the same expenses.32Average Annual Total Returns -
Adv
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