XML 15 R1.htm IDEA: XBRL DOCUMENT

Total

American Century Government Income Trust | CAPITAL PRESERVATION FUND

Capital Preservation Fund

Investment Objective

The fund is a money market fund that seeks maximum safety and liquidity.

Its secondary objective is to seek to pay shareholders the highest rate of return consistent with safety and liquidity.

Fees and Expenses

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	USD ($)
Maximum Account Fee \| American Century Government Income Trust \| CAPITAL PRESERVATION FUND \| INVESTOR CLASS	$ 25

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

Annual Fund Operating Expenses	American Century Government Income Trust CAPITAL PRESERVATION FUND INVESTOR CLASS
Management Fees (as a percentage of Assets)	0.47%
Distribution and Service (12b-1) Fees	none
Other Expenses (as a percentage of Assets):	0.01%
Net Expenses (as a percentage of Assets)	0.48%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs 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 you earn a 5% return each year and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
American Century Government Income Trust \| CAPITAL PRESERVATION FUND \| INVESTOR CLASS \| USD ($)	49	154	269	604

Principal Investment Strategies

Under normal circumstances, Capital Preservation invests exclusively in short-term money market securities issued by the U.S. Treasury that are guaranteed by the direct full faith and credit pledge of the U.S. government. The income from these securities is exempt from state income tax. Examples of U.S. Treasury securities in which the fund may invest include Treasury bills and notes, and Treasury floating-rate notes.

Because this fund is a government money market fund, both retail and institutional shareholders may invest in the fund. This fund does not have the ability to impose a liquidity fee on the sale of shares or temporarily suspend redemptions in response to decreases in liquidity.

The fund may purchase U.S. Treasury securities through buy/sell back transactions. The fund may commit up to 35% of its total assets to such transactions.

Principal Risks

Because short-term money market securities are among the safest securities available, the interest they pay is among the lowest for income-paying securities. Accordingly, the yield on this fund will likely be lower than the yield on funds that invest in longer-term or lower-quality securities.

Investments in U.S. Treasury securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. The fund’s investments in short-term U.S. Treasury securities are designed to minimize this risk. However, a sharp and unexpected rise in interest rates could cause the fund’s share price to drop.

You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The fund’s sponsor has no legal obligation to provide financial support to the fund, and you should not expect that the sponsor will provide financial support to the fund at any time.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The fund’s past performance is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

(1Q 2019): 0.49% Lowest Performance Quarter (2Q 2015): 0.00%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 0.24%.

Average Annual Total Returns For the calendar year ended December 31, 2019

Average Annual Total Returns	Label	1 Year	5 Years	10 Years
American Century Government Income Trust \| CAPITAL PRESERVATION FUND \| INVESTOR CLASS	Investor Class	1.75%	0.71%	0.36%

American Century Government Income Trust | GINNIE MAE FUND

Ginnie Mae Fund

Investment Objective

Ginnie Mae seeks high current income while maintaining liquidity and safety of principal by investing primarily in GNMA certificates.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 30 of the fund’s prospectus, Appendix A of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees - American Century Government Income Trust - GINNIE MAE FUND - USD ($)	INVESTOR CLASS	I CLASS	A CLASS		C CLASS	R CLASS	R5 CLASS
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	none	none	4.50%		none	none	none
Maximum Deferred Sales Charge (as a percentage)	none	none	none	^[1]	1.00%	none	none
Maximum Account Fee	$ 25	none	none		none	none	none

[1]	Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase.

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

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example - American Century Government Income Trust - GINNIE MAE FUND - USD ($)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
INVESTOR CLASS	56	177	308	690
I CLASS	46	145	252	567
A CLASS	528	694	875	1,396
C CLASS	158	490	845	1,844
R CLASS	107	335	580	1,282
R5 CLASS	36	113	197	444

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 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 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 270% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the fund invests at least 80% of its net assets in securities issued by the Government National Mortgage Association (GNMA). GNMA certificates represent interests in pools of mortgage loans and in the cash flows from these loans. Unlike many other mortgage-backed securities, the timely payment of principal and interest on these certificates is guaranteed by GNMA. GNMA’s payment guarantee is stronger than most other government agencies’ because it is backed by the full faith and credit pledge of the U.S. government.

In addition, the fund may buy other U.S. government debt securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, these agencies or instrumentalities are authorized to borrow from the U.S. Treasury to meet their obligations.

To generate additional income, the fund may purchase securities, including mortgage dollar rolls, in advance through when-issued and forward commitment transactions. The fund may commit up to 35% of its total assets to such transactions.

The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts and swap agreements, or in mortgage- or asset-backed securities, provided that such investments are in keeping with the fund’s investment objective.

When determining whether to sell a security, the portfolio managers consider, among other things, current and anticipated changes in interest rates, current valuation relative to alternatives in the market, general market conditions and any other factors deemed relevant by the portfolio managers.

The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.

Principal Risks


•	Interest Rate Risk—Generally, when interest rates rise, the fund’s share value will decline. The opposite is true when interest rates decline. This risk is higher for the fund than for other funds that have shorter weighted average maturities, such as money market funds and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.


•	Prepayment Risk—The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds that have similar weighted average maturities.


•	Derivatives Risk—The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks including liquidity, interest rate, market, credit and correlation risk.

•

Market Risk—The value of the securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.

•

Redemption Risk—The fund may need to sell securities at times it would not otherwise do so in order to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.


•	Principal Loss—At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

(2Q 2010): 3.21% Lowest Performance Quarter (2Q 2013): -2.72%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 3.47%.

Average Annual Total Returns For the calendar year ended December 31, 2019

Average Annual Total Returns - American Century Government Income Trust - GINNIE MAE FUND		Label	1 Year	5 Years	10 Years
Bloomberg Barclays U.S. GNMA Index		Bloomberg Barclays U.S. GNMA Index (reflects no deduction for fees, expenses or taxes)	5.85%	2.32%	3.21%
INVESTOR CLASS		Investor Class Return Before Taxes	6.16%	1.90%	2.77%
INVESTOR CLASS \| After Taxes on Distributions		Return After Taxes on Distributions	5.00%	0.84%	1.61%
INVESTOR CLASS \| After Taxes on Distributions and Sales		Return After Taxes on Distributions and Sale of Fund Shares	3.63%	0.97%	1.65%
I CLASS	^[1]	I Class1 Return Before Taxes	6.27%	2.01%	2.87%
A CLASS	^[2]	A Class2 Return Before Taxes	1.14%	0.72%	2.05%
C CLASS	^[3]	C Class3 Return Before Taxes	5.11%	0.89%	1.75%
R CLASS		R Class Return Before Taxes	5.64%	1.39%	2.25%
R5 CLASS		R5 Class Return Before Taxes	6.37%	2.10%	2.98%

[1]	Historical performance for the I Class prior to its inception (April 10, 2017) is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[2]	Prior to March 1, 2010, the A Class was referred to as the Advisor Class and did not have a front-end sales charge. Performance prior to that date has been restated to reflect this charge.
[3]	Historical performance for the C Class prior to its inception (March 1, 2010) is based on the performance of Investor Class shares. C Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes.

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

American Century Government Income Trust | GOVERNMENT BOND FUND

Government Bond Fund

Investment Objective

The fund seeks high current income.

Fees and Expenses

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees - American Century Government Income Trust - GOVERNMENT BOND FUND - USD ($)	INVESTOR CLASS	I CLASS	A CLASS		C CLASS	R CLASS	R5 CLASS
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	none	none	4.50%		none	none	none
Maximum Deferred Sales Charge (as a percentage)	none	none	none	^[1]	1.00%	none	none
Maximum Account Fee	$ 25	none	none		none	none	none

[1]	Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase.

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

Annual Fund Operating Expenses - American Century Government Income Trust - GOVERNMENT BOND FUND	INVESTOR CLASS	I CLASS	A CLASS	C CLASS	R CLASS	R5 CLASS
Management Fees (as a percentage of Assets)	0.46%	0.36%	0.46%	0.46%	0.46%	0.26%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%	none
Other Expenses (as a percentage of Assets):	0.01%	0.01%	0.01%	0.01%	0.01%	0.01%
Net Expenses (as a percentage of Assets)	0.47%	0.37%	0.72%	1.47%	0.97%	0.27%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example - American Century Government Income Trust - GOVERNMENT BOND FUND - USD ($)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
INVESTOR CLASS	48	151	264	592
I CLASS	38	119	208	469
A CLASS	520	670	833	1,305
C CLASS	150	466	803	1,756
R CLASS	99	310	537	1,190
R5 CLASS	28	87	152	344

Portfolio Turnover

Principal Investment Strategies

Under normal market conditions, the fund invests at least 80% of its net assets in U.S. government debt securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities.

Securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities, such as the Government National Mortgage Association (Ginnie Mae), are supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, these agencies or instrumentalities are authorized to borrow from the U.S. Treasury to meet their obligations.

Principal Risks


•	Interest Rate Risk—Generally, when interest rates rise, the fund’s share value will decline. The opposite is true when interest rates decline. This risk is higher for the fund than for other funds that have shorter weighted average maturities, such as money market funds or short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.


•	Prepayment Risk—The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds that have similar weighted average maturities.


•	Derivatives Risk—The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks including liquidity, interest rate, market, credit and correlation risk.

•


•	Principal Loss—At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

(3Q 2011): 4.45% Lowest Performance Quarter (4Q 2016): -3.17%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 6.47%.

Average Annual Total Returns For the calendar year ended December 31, 2019

Average Annual Total Returns - American Century Government Income Trust - GOVERNMENT BOND FUND		Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
Bloomberg Barclays U.S. Government/MBS Index		Bloomberg Barclays U.S. Government/MBS Index (reflects no deduction for fees, expenses or taxes)	6.63%	2.45%	3.07%
INVESTOR CLASS		Investor Class Return Before Taxes	6.16%	2.02%	2.65%		May 16, 1980
INVESTOR CLASS \| After Taxes on Distributions		Return After Taxes on Distributions	5.08%	1.09%	1.67%		May 16, 1980
INVESTOR CLASS \| After Taxes on Distributions and Sales		Return After Taxes on Distributions and Sale of Fund Shares	3.63%	1.12%	1.64%		May 16, 1980
I CLASS	^[1]	I Class1 Return Before Taxes	6.27%	2.11%		2.63%	Apr. 10, 2017
A CLASS	^[2]	A Class2 Return Before Taxes	1.09%	0.85%	1.92%		Oct. 09, 1997
C CLASS	^[3]	C Class3 Return Before Taxes	5.21%	1.03%	1.63%		Mar. 01, 2010
R CLASS	^[3]	R Class3 Return Before Taxes	5.63%	1.53%	2.14%		Mar. 01, 2010
R5 CLASS		R5 Class Return Before Taxes	6.37%	2.24%		2.75%	Mar. 01, 2010

[1]	Historical performance for the I Class prior to its inception is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable. Since inception performance for the I Class is based on the R5 Class inception date.
[2]	Prior to March 1, 2010, the A Class was referred to as the Advisor Class and did not have a front-end sales charge. Performance prior to that date has been restated to reflect this charge.
[3]	Historical performance for the C and R Classes prior to their inception is based on the performance of Investor Class shares. C and R Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes.

American Century Government Income Trust | SHORT-TERM GOVERNMENT FUND

Short-Term Government Fund

Investment Objective

The fund seeks high current income while maintaining safety of principal.

Fees and Expenses

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees - American Century Government Income Trust - SHORT-TERM GOVERNMENT FUND - USD ($)	INVESTOR CLASS	I CLASS	A CLASS		C CLASS	R CLASS	R5 CLASS
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	none	none	2.25%		none	none	none
Maximum Deferred Sales Charge (as a percentage)	none	none	none	^[1]	1.00%	none	none
Maximum Account Fee	$ 25	none	none		none	none	none

[1]	Purchases of $500,000 or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase.

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

Annual Fund Operating Expenses - American Century Government Income Trust - SHORT-TERM GOVERNMENT FUND	INVESTOR CLASS	I CLASS	A CLASS	C CLASS	R CLASS	R5 CLASS
Management Fees (as a percentage of Assets)	0.54%	0.44%	0.54%	0.54%	0.54%	0.34%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%	none
Other Expenses (as a percentage of Assets):	0.01%	0.01%	0.01%	0.01%	0.01%	0.01%
Net Expenses (as a percentage of Assets)	0.55%	0.45%	0.80%	1.55%	1.05%	0.35%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example - American Century Government Income Trust - SHORT-TERM GOVERNMENT FUND - USD ($)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
INVESTOR CLASS	56	177	308	690
I CLASS	46	145	252	567
A CLASS	305	475	660	1,193
C CLASS	158	490	845	1,844
R CLASS	107	335	580	1,282
R5 CLASS	36	113	197	444

Portfolio Turnover

Principal Investment Strategies

Under normal market conditions, the fund buys short-term debt securities and will invest at least 80% of its net assets in U.S. government securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. In addition, the fund may invest a portion of its assets in investment-grade debt securities, including debt securities of U.S. companies, and non-U.S. government mortgage-backed, asset-backed and other fixed-income securities. Under normal market conditions, the portfolio managers maintain a weighted average maturity of three years or less.

The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swap agreements), or in mortgage- or asset-backed securities, provided that such investments are in keeping with the fund’s investment objective.

Principal Risks


•	Interest Rate Risk—Generally, when interest rates rise, the fund’s share value will decline. The opposite is true when interest rates decline. This risk is higher for the fund than for other funds that have shorter weighted average maturities, such as money market funds. A period of rising interest rates may negatively affect the fund’s performance.


•	Prepayment Risk—The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds that have similar weighted average maturities.


•	Derivatives Risk—The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks including liquidity, interest rate, market, credit and correlation risk.

•


•	Principal Loss—At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Return

(2Q 2010): 1.30% Lowest Performance Quarter (2Q 2013): -0.53%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 3.01%.

Average Annual Total Returns For the calendar year ended December 31, 2019

Average Annual Total Returns - American Century Government Income Trust - SHORT-TERM GOVERNMENT FUND		Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
Bloomberg Barclays U.S. 1-3 Year Government Bond Index		Bloomberg Barclays U.S. 1-3 Year Government Bond Index (reflects no deduction for fees, expenses or taxes)	3.59%	1.40%	1.25%
INVESTOR CLASS		Investor Class Return Before Taxes	2.91%	0.95%	0.87%		Dec. 15, 1982
INVESTOR CLASS \| After Taxes on Distributions		Return After Taxes on Distributions	2.15%	0.46%	0.48%		Dec. 15, 1982
INVESTOR CLASS \| After Taxes on Distributions and Sales		Return After Taxes on Distributions and Sale of Fund Shares	1.72%	0.51%	0.52%		Dec. 15, 1982
I CLASS	^[1]	I Class1 Return Before Taxes	3.01%	1.05%		0.90%	Apr. 10, 2017
A CLASS	^[2]	A Class2 Return Before Taxes	0.32%	0.26%	0.40%		Jul. 08, 1998
C CLASS	^[3]	C Class3 Return Before Taxes	1.91%	(0.03%)	(0.12%)		Mar. 01, 2010
R CLASS	^[3]	R Class3 Return Before Taxes	2.40%	0.46%	0.38%		Mar. 01, 2010
R5 CLASS		R5 Class Return Before Taxes	3.22%	1.17%		1.01%	Mar. 01, 2010

[1]	Historical performance for the I Class prior to its inception is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable. Since inception performance for the I Class is based on the R5 Class inception date.
[2]	Prior to March 1, 2010, the A Class was referred to as the Advisor Class and did not have a front-end sales charge. Performance prior to that date has been restated to reflect this charge.
[3]	Historical performance for the C and R Classes prior to their inception is based on the performance of Investor Class shares. C and R Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes.

American Century Government Income Trust | INFLATION-ADJUSTED BOND FUND

Inflation-Adjusted Bond Fund

Investment Objective

The fund seeks to provide total return and inflation protection consistent with investment in inflation-indexed securities.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 15 of the fund’s prospectus, Appendix A of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees - American Century Government Income Trust - INFLATION-ADJUSTED BOND FUND - USD ($)	INVESTOR CLASS	I CLASS	Y CLASS	A CLASS		C CLASS	R CLASS	R5 CLASS	R6 CLASS	G CLASS
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	none	none	none	4.50%		none	none	none	none	none
Maximum Deferred Sales Charge (as a percentage)	none	none	none	none	^[1]	1.00%	none	none	none	none
Maximum Account Fee	$ 25	none	none	none		none	none	none	none	none

[1]	Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase.

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

Annual Fund Operating Expenses - American Century Government Income Trust - INFLATION-ADJUSTED BOND FUND	INVESTOR CLASS	I CLASS	Y CLASS	A CLASS	C CLASS	R CLASS	R5 CLASS	R6 CLASS	G CLASS
Management Fees (as a percentage of Assets)	0.46%	0.36%	0.26%	0.46%	0.46%	0.46%	0.26%	0.21%	0.21%
Distribution and Service (12b-1) Fees	none	none	none	0.25%	1.00%	0.50%	none	none	none
Other Expenses (as a percentage of Assets):	0.01%	0.01%	0.01%	0.01%	0.01%	0.01%	0.01%	0.01%	0.01%
Expenses (as a percentage of Assets)	0.47%	0.37%	0.27%	0.72%	1.47%	0.97%	0.27%	0.22%	0.22%
Fee Waiver or Reimbursement	none	none	none	none	none	none	none	none	(0.21%)	^[1]
Net Expenses (as a percentage of Assets)	0.47%	0.37%	0.27%	0.72%	1.47%	0.97%	0.27%	0.22%	0.01%

[1]	The advisor has agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees.

Example

The example below is intended to help you compare the costs of investing in the fund with the costs 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, and that you earn a 5% return each year. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - American Century Government Income Trust - INFLATION-ADJUSTED BOND FUND - USD ($)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
INVESTOR CLASS	48	151	264	592
I CLASS	38	119	208	469
Y CLASS	28	87	152	344
A CLASS	520	670	833	1,305
C CLASS	150	466	803	1,756
R CLASS	99	310	537	1,190
R5 CLASS	28	87	152	344
R6 CLASS	23	71	124	281
G CLASS	1	3	6	13

Portfolio Turnover

Principal Investment Strategies

Under normal market conditions, the fund invests at least 80% of its net assets in inflation-adjusted bonds. The advisor considers inflation-adjusted bonds to include inflation-indexed bonds, notes, commercial paper, short-term instruments and other debt securities issued by the U.S. Treasury, by other U.S. government agencies and instrumentalities, and by other, non-U.S. government entities such as corporations and foreign governments. Inflation-indexed securities are designed to protect the future purchasing power of the money invested in them; their principal value may be indexed for changes in inflation. In addition, the fund may invest a portion of its assets in traditional U.S. Treasury, U.S. government agency or other non-U.S. government securities that are not inflation-indexed.

The fund invests primarily in investment-grade securities, but may also invest a portion of its assets in high-yield securities, or junk bonds. A high-yield security is one that has been rated below the four highest categories by a nationally recognized rating organization.

There are no maturity or duration restrictions for the securities in which the fund may invest.

Although the fund invests primarily in U.S. dollar-denominated securities, the fund also may invest in securities denominated in foreign currencies.

The fund also may invest in derivative instruments such as futures contracts and swap agreements (including, but not limited to, inflation swap agreements and credit default swap agreements), bank loans, securities backed by mortgages or other assets and collateralized debt obligations (including collateralized loan obligations). The fund may invest in U.S. Treasury futures, inflation swap agreements and credit default swap agreements to manage duration, inflation and credit exposure.

Principal Risks

•

Inflation-Indexed Bonds Risk—If the index measuring inflation falls, the principal value of inflation-indexed bonds will be adjusted downward, and consequently the interest payable on these securities will be reduced. In addition, interest payments on inflation-indexed bonds may be difficult to predict and may vary as the principal and/or interest is adjusted for inflation. In periods of deflation, the fund may have no income at all from such investments.

•

Interest Rate Risk—Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. The fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.


•	Credit Risk—The value of the fund’s debt securities will be affected adversely by the inability or perceived inability of the issuers of these securities to make interest and principal payments as they become due. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.

•

High-Yield Risk—Issuers of high-yield securities, or junk bonds, are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations. High-yield securities (junk bonds) are also inherently speculative.

•

Liquidity Risk—During periods of market turbulence or unusually low trading activity, in order to meet redemptions it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund’s share price. The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.


•	Foreign Securities Risk—Foreign securities have certain unique risks, such as currency risk, social, political and economic risk, and foreign market and trading risk. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.

•

Bank Loan Risk — The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.

•

Collateralized Debt Obligations Risk — Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.

•

Derivatives Risk—The use of derivative instruments involves risks different from the risks associated with investing directly in securities and other traditional instruments. The fund’s use of derivatives, and in particular its use of inflation swap agreements and credit default swap agreements, are subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation. Derivatives are also subject to a number of additional risks including liquidity, interest rate, market, credit and correlation risk. In addition, gains or losses involving some futures and other derivatives may be substantial - in part because a relatively small price movement in these securities may result in an immediate and substantial gain or loss for the fund.

•

When-Issued and Forward Commitment Risk—When-issued and forward commitments involve the risk that the security the fund buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the fund may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security’s price.


•	Mortgage- and Asset-Backed Securities Risks—Mortgage- and asset backed securities are subject to credit, interest rate, prepayment and extension risks. These securities also are subject to risk of default on the underlying mortgage or asset, particularly during periods of economic downturn.

•

Mortgage Dollar Rolls Risk—If the counterparty to whom the fund sells the security becomes insolvent, the fund’s right to repurchase the security may be restricted. Other risks involved in entering into mortgage dollar rolls include the risk that the value of the security may change adversely over the term of the mortgage dollar roll and that the security the fund is required to repurchase may be worth less than the security that the fund originally held.


•	Principal Loss—At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

(3Q 2011): 4.66% Lowest Performance Quarter (2Q 2013): -7.52%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 5.09%.

Average Annual Total Returns For the calendar year ended December 31, 2019

Average Annual Total Returns - American Century Government Income Trust - INFLATION-ADJUSTED BOND FUND		Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index		Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (reflects no deduction for fees, expenses or taxes)	8.43%	2.61%	3.36%
INVESTOR CLASS		Investor Class Return Before Taxes	7.85%	2.12%	2.80%		Feb. 10, 1997
INVESTOR CLASS \| After Taxes on Distributions		Return After Taxes on Distributions	6.79%	1.22%	1.81%		Feb. 10, 1997
INVESTOR CLASS \| After Taxes on Distributions and Sales		Return After Taxes on Distributions and Sale of Fund Shares	4.64%	1.22%	1.80%		Feb. 10, 1997
I CLASS	^[1]	I Class1 Return Before Taxes	7.87%	2.19%	2.89%		Apr. 10, 2017
Y CLASS	^[1]	Y Class1 Return Before Taxes	7.98%	2.30%	2.99%		Apr. 10, 2017
A CLASS	^[2]	A Class2 Return Before Taxes	2.65%	0.93%	2.07%		Jun. 15, 1998
C CLASS	^[3]	C Class3 Return Before Taxes	6.77%	1.10%	1.77%		Mar. 01, 2010
R CLASS	^[3]	R Class3 Return Before Taxes	7.29%	1.61%	2.28%		Mar. 01, 2010
R5 CLASS		R5 Class Return Before Taxes	8.07%	2.33%	3.00%		Oct. 01, 2002
R6 CLASS		R6 Class Return Before Taxes	8.14%			3.01%	Jul. 28, 2017
G CLASS		G Class Return Before Taxes	8.35%			3.25%	Jul. 28, 2017

[1]	Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[2]	Prior to March 1, 2010, the A Class was referred to as the Advisor Class and did not have a front-end sales charge. Performance prior to that date has been restated to reflect this charge.
[3]	Historical performance for the C and R Classes prior to their inception is based on the performance of Investor Class shares. C and R Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes.