Investment Strategy	Aug. 31, 2024
Schwab Short-Term Bond Index Fund
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	To pursue its goal, the fund generally invests in securities that are included in the Bloomberg US Government/Credit 1-5 Year Index†. The index is a broad-based benchmark measuring the performance of U.S. dollar-denominated U.S. Treasury bonds, government related bonds (i.e., U.S. and non-U.S. agencies, sovereign, quasi-sovereign, supranational and local authority debt) and investment grade U.S. corporate bonds that have a remaining maturity of greater than or equal to one year and less than five years. To be eligible for inclusion in the index, securities must be fixed rate, non-convertible, U.S. dollar-denominated with at least $300 million or more of outstanding face value and have a remaining maturity greater than or equal to one year and less than five years. The index excludes certain types of securities, including, bonds with equity type features (e.g., warrants, convertibles and preferreds), tax-exempt municipal securities, inflation-linked bonds, floating rate issues, strips, private placements, U.S. dollar-denominated 25 and 50 par retail bonds, structured notes and pass-through certificates. The index is market capitalization weighted and the securities in the index are updated on the last business day of each month. It is the fund’s policy that under normal circumstances it will invest at least 90% of its net assets (including, for this purpose, any borrowings for investment purposes) in securities included in the index. The fund will notify its shareholders at least 60 days before changing this policy. Under normal circumstances, the fund may invest up to 10% of its net assets in securities not included in its index. The principal types of these investments include those that the investment adviser believes will help the fund track the index, such as investments in (a) securities that are not represented in the index but the investment adviser anticipates will be added to the index; (b) high-quality liquid investments, such as securities issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, and obligations that are issued by private issuers; (c) other investment companies; and (d) derivatives, principally futures contracts. The fund may use futures contracts and other derivatives primarily to help manage interest rate exposure. The fund may also invest in cash and cash equivalents, including money market funds, and lend its securities to minimize the difference in performance that naturally exists between an index fund and its corresponding index. Because it is not possible or practical to purchase all of the securities in the index, the fund’s investment adviser will seek to track the total return of the index by using sampling techniques. † Index ownership – Bloomberg® and Bloomberg US Government/Credit 1-5 Year Index are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (BISL), the administrator of the indices (collectively, “Bloomberg”). Bloomberg is not affiliated with Charles Schwab Investment Management, Inc., dba Schwab Asset Management, and Bloomberg does not approve, endorse, review, or recommend Schwab Short-Term Bond Index Fund. Bloomberg does not guarantee the timeliness, accurateness, or completeness of any data or information relating to Schwab Short-Term Bond Index Fund. Sampling techniques involve investing in a limited number of index securities that, when taken together, are expected to perform similarly to the index as a whole. These techniques are based on a variety of factors, including interest rate and yield curve risk, maturity exposures, industry, sector and issuer weights, credit quality, and other risk factors and characteristics. The fund expects that its portfolio will hold less than the total number of securities in the index, but reserves the right to hold as many securities as it believes necessary to achieve the fund’s investment objective. The fund may sell securities that are represented in the index in anticipation of their removal from the index. In addition, the fund generally expects that its duration will closely correspond to the duration of the index, which as of August 31, 2024 was approximately 2.54 years. The fund will concentrate its investments (i.e., hold more than 25% of its total assets) in a particular industry, group of industries or sector to approximately the same extent that its index is so concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities), and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry.
Schwab Treasury Inflation Protected Securities Index Fund
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	To pursue its goal, the fund generally invests in securities that are included in the Bloomberg US Treasury Inflation-Linked Bond Index† (Series-L)SM. The index includes all publicly-issued treasury inflation-protected securities (TIPS) that have at least one year remaining to maturity, are rated investment grade and have $500 million or more of outstanding face value. The TIPS in the index must be denominated in U.S. dollars and must be fixed-rate and non-convertible. The index is market capitalization weighted and the TIPS in the index are updated on the last business day of each month. TIPS are publicly issued, dollar-denominated U.S. government securities issued by the U.S. Treasury that have principal and interest payments linked to an official inflation measure (as measured by the Consumer Price Index, or CPI) and their payments are supported by the full faith and credit of the United States. It is the fund’s policy that, under normal circumstances, it will invest at least 90% of its net assets (including, for this purpose, any borrowings for investment purposes) in securities included in the index. The fund will notify its shareholders at least 60 days before changing this policy. The fund will generally seek to replicate the performance of the index by giving the same weight to a given security as the index does. However, when the investment adviser believes it is in the best interest of the fund, such as to avoid purchasing odd-lots (i.e., purchasing less than the usual number of shares traded for a security), for tax considerations, or to address liquidity considerations with respect to a security, the investment adviser may cause the fund’s weighting of a security to be more or less than the index’s weighting of the security. The fund may sell securities that are represented in the index in anticipation of their removal from the index. Under normal circumstances, the fund may invest up to 10% of its net assets in securities not included in the index. The principal types of these investments include those that the investment adviser believes will help the fund track the index, such as investments in (a) securities that are not represented in the index but the investment adviser anticipates will be added to the index; (b) high-quality liquid investments, such as securities issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, and obligations that are issued by private issuers that are guaranteed as to principal or interest by the U.S. government, its agencies or instrumentalities, and (c) investment companies. The fund may also invest in cash and cash equivalents, including money market funds, enter into † Index ownership – Bloomberg® and Bloomberg US Treasury Inflation-Linked Bond Index are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (BISL), the administrator of the indices (collectively, “Bloomberg”). Bloomberg is not affiliated with Charles Schwab Investment Management, Inc.,dba Schwab Asset Management, and Bloomberg does not approve, endorse, review, or recommend Schwab Treasury Inflation Protected Securities Index Fund. Bloomberg does not guarantee the timeliness, accurateness, or completeness of any data or information relating to Schwab Treasury Inflation Protected Securities Index Fund. repurchase agreements, and may lend its securities to minimize the difference in performance that naturally exists between an index fund and its corresponding index. The investment adviser typically seeks to track the price and yield performance of the index by replicating the index. This means that the fund generally expects that it will hold the same securities as those included in the index. However, the investment adviser may use sampling techniques if the investment adviser believes such use will best help the fund to track the index or is otherwise in the best interest of the fund. Sampling techniques involve investing in a limited number of index securities that, when taken together, are expected to perform similarly to the index as a whole. These techniques are based on a variety of factors, including interest rate and yield curve risk, maturity exposures, and other risk factors and characteristics. When the fund uses sampling techniques, the fund generally expects that its yield, maturity and weighted average effective duration will be similar to those of the index.
Schwab U.S. Aggregate Bond Index Fund
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	To pursue its goal, the fund generally invests in securities that are included in the Bloomberg US Aggregate Bond Index†. The index is a broad-based benchmark measuring the performance of the U.S. investment grade, taxable bond market, including U.S. Treasuries, government-related and corporate bonds, mortgage pass-through securities, commercial mortgage-backed securities, and asset-backed securities that are publicly available for sale in the United States. To be eligible for inclusion in the index, a security must be fixed rate, non-convertible, U.S. dollar-denominated and have one or more years remaining to maturity. The index excludes certain types of securities, including, bonds with equity type features (e.g., warrants, convertibles and preferreds), tax-exempt municipal securities, inflation-linked bonds, floating-rate issues, strips, private placements, U.S. dollar-denominated 25 and 50 par retail bonds, structured notes and pass-through certificates. The index is market capitalization weighted and the securities in the index are updated on the last business day of each month. It is the fund’s policy that under normal circumstances it will invest at least 90% of its net assets (including, for this purpose, any borrowings for investment purposes) in securities included in the index, including TBA transactions, as defined below. The fund will notify its shareholders at least 60 days before changing this policy. Under normal circumstances, the fund may invest up to 10% of its net assets in securities not included in its index. The principal types of these investments include those that the investment adviser believes will help the fund track the index, such as investments in (a) securities that are not represented in the index but the investment adviser anticipates will be added to the index; (b) high-quality liquid investments, such as securities issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, and obligations that are issued by private issuers; (c) other investment companies; and (d) derivatives, principally futures contracts. The fund may use futures contracts and other derivatives primarily to help manage interest rate exposure. The fund may also invest in cash and cash equivalents, including money market funds, and lend its securities to minimize the difference in performance that naturally exists between an index fund and its corresponding index. Because it is not possible or practical to purchase all of the securities in the index, the fund’s investment adviser will seek to track the total return of the index by using sampling techniques. Sampling techniques involve investing in a limited number of index securities that, when taken together, are expected to perform similarly to the index as a whole. These techniques are based on a variety of factors, including interest rate and yield curve risk, maturity exposures, industry, sector and issuer weights, credit quality, and other risk factors and characteristics. The fund expects that its † Index ownership – Bloomberg® and Bloomberg US Aggregate Bond Index are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (BISL), the administrator of the indices (collectively, “Bloomberg”). Bloomberg is not affiliated with Charles Schwab Investment Management, Inc., dba Schwab Asset Management, and Bloomberg does not approve, endorse, review, or recommend Schwab U.S. Aggregate Bond Index Fund. Bloomberg does not guarantee the timeliness, accurateness, or completeness of any data or information relating to Schwab U.S. Aggregate Bond Index Fund. portfolio will hold less than the total number of securities in the index, but reserves the right to hold as many securities as it believes necessary to achieve the fund’s investment objective. The fund may sell securities that are represented in the index in anticipation of their removal from the index. The fund generally expects that its duration will closely correspond to the duration of the index, which as of August 31, 2024, was approximately 6.08 years. As of August 31, 2024, approximately 25.52% of the bonds represented in the index were U.S. fixed-rate agency mortgage pass-through securities. U.S. fixed-rate agency mortgage pass-through securities are securities issued by entities such as the Government National Mortgage Association (Ginnie Mae), the Federal National Mortgage Association (Fannie Mae), and the Federal Home Loan Mortgage Corporation (Freddie Mac) that are backed by pools of mortgages. Many transactions in fixed-rate mortgage pass-through securities occur through standardized contracts for future delivery in which the exact mortgage pools to be delivered are not specified until a few days prior to settlement, and are often referred to as “to-be-announced transactions” or “TBA transactions.” In a TBA transaction, the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to settlement date; however, it is not anticipated that the fund will receive the pools, but will instead participate in rolling TBA transactions. The fund anticipates that it may enter into such contracts on a regular basis. This may result in a significantly higher portfolio turnover for the fund than a typical index fund. The fund, pending settlement of such contracts, will invest its assets in high-quality liquid short-term instruments, including Treasury securities and shares of money market mutual funds. The fund will assume its pro rata share of the fees and expenses of any money market fund that it may invest in, in addition to the fund’s own fees and expenses. The fund will concentrate its investments (i.e., hold more than 25% of its total assets) in a particular industry, group of industries or sector to approximately the same extent that its index is so concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities), and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry.
Schwab Tax-Free Bond Fund
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	To pursue its goal, the fund primarily invests in investment-grade municipal securities – those in the four highest credit rating categories (rated AAA to BBB- or the unrated equivalent as determined by the investment adviser). The fund normally invests at least 80% of its net assets (including, for this purpose, any borrowings for investment purposes) in municipal securities the interest from which is exempt from federal income tax, including the federal alternative minimum tax (AMT). The fund may invest in fixed-, variable- or floating-rate securities from municipal issuers around the country and in U.S. territories and possessions. These may include general obligation issues, which typically are backed by the issuer’s ability to levy taxes, and revenue issues, which typically are backed by a stream of revenue from a given source, such as an electric utility or a public water system. The fund may invest more than 25% of its total assets in municipal securities financing similar projects, such as those relating to education, health care, transportation and utilities and may also invest in municipal notes. The fund’s securities may carry credit enhancements (such as bond insurance) or liquidity enhancements (such as a letter of credit), which are designed to provide incremental levels of creditworthiness or liquidity. In choosing securities, the fund’s investment adviser seeks to maximize current income within the limits of the fund’s credit and maturity standards. The investment adviser’s credit research department analyzes and monitors the securities that the fund owns or is considering buying. The fund may invest up to 15% of its assets in below investment grade bonds (sometimes called junk bonds) that are rated, at the time of investment, at least B by at least one nationally recognized statistical rating organization or are the unrated equivalent as determined by the investment adviser. If a bond is downgraded below B or the unrated equivalent, the fund may continue to hold it unless the investment adviser determines the risk of holding the bond is unacceptable when compared to the bond’s total return potential. The investment adviser may adjust the fund’s holdings based on actual or anticipated changes in interest rates or credit quality. The fund may also invest in derivative instruments, principally futures contracts. The fund typically uses futures as a substitute for taking a position in the underlying asset or as a part of a strategy designed to reduce exposure to other risks. During unusual market conditions, the fund may invest entirely in taxable securities and municipal securities whose interest is subject to federal income tax and the AMT as a temporary defensive measure. When the fund engages in such activities, the fund would not be pursuing its investment strategy and, as a result, it may not achieve its investment objective.
Schwab California Tax-Free Bond Fund
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	To pursue its goal, the fund primarily invests in investment-grade municipal securities – those in the four highest credit rating categories (rated AAA to BBB- or the unrated equivalent as determined by the investment adviser) from California issuers. The fund normally invests at least 80% of its net assets (including, for this purpose, any borrowings for investment purposes) in municipal securities the interest from which is exempt from federal and California personal income tax and federal alternative minimum tax (AMT). These securities may include those issued by issuers located outside of California, such as U.S. territories and possessions, or by their agencies, authorities, or instrumentalities. The fund may invest in securities from municipal issuers in California and in U.S. territories and possessions. These may include general obligation issues, which typically are backed by the issuer’s ability to levy taxes, and revenue issues, which typically are backed by a stream of revenue from a given source, such as an electric utility or a public water system. The fund may invest more than 25% of its total assets in municipal securities financing similar projects, such as those relating to education, health care, transportation and utilities and may also invest in municipal notes. The fund’s securities may carry credit enhancements (such as bond insurance) or liquidity enhancements (such as a letter of credit), which are designed to provide incremental levels of creditworthiness or liquidity. In choosing securities, the fund’s investment adviser seeks to maximize current income within the limits of the fund’s credit and maturity standards. The investment adviser’s credit research department analyzes and monitors the securities that the fund owns or is considering buying. The fund may invest up to 15% of its assets in below investment grade bonds (sometimes called junk bonds) that are rated, at the time of investment, at least B by at least one nationally recognized statistical rating organization or are the unrated equivalent as determined by the investment adviser. If a bond is downgraded below B or the unrated equivalent, the fund may continue to hold it unless the investment adviser determines the risk of holding the bond is unacceptable when compared to the bond’s total return potential. The investment adviser may adjust the fund’s holdings based on actual or anticipated changes in interest rates or credit quality. The fund may also invest in derivative instruments, principally futures contracts. The fund typically uses futures as a substitute for taking a position in the underlying asset or as a part of a strategy designed to reduce exposure to other risks. During unusual market conditions, the fund may invest entirely in taxable securities and municipal securities whose interest is subject to federal income tax and the AMT, and also California personal income tax, as a temporary defensive measure. When the fund engages in such activities, the fund would not be pursuing its investment strategy and, as a result, it may not achieve its investment objective.
Schwab Opportunistic Municipal Bond Fund
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	Under normal market conditions, the fund invests at least 80% of its net assets (including, for this purpose, any borrowings for investment purposes) in municipal securities that pay interest not subject to regular federal income tax. Some of these investments in municipal securities may pay interest that is not exempt from the federal alternative minimum tax (AMT). Municipal securities may include debt obligations of U.S. states, territories, counties, cities, political subdivisions, government agencies and instrumentalities. The fund also invests in non-governmental municipal issuers, including, but not limited to, healthcare organizations, corporate issuers of municipal debt, and various project finance bond issues. The fund primarily invests in general obligation and revenue obligation securities, including fixed and variable rate securities, municipal notes and private placements, auction-rate securities, variable rate demand notes, lease-backed obligations and certificates of participation. The fund may from time to time invest temporarily up to 20% of its net assets in taxable securities of at least comparable quality to the municipal securities in which the Fund invests. The fund may also invest up to 25% of its net assets in municipal securities that are subject to the AMT. The fund has no policy limiting its investments in municipal securities whose issuers are located in the same state or territory. However, the fund currently intends to invest no more than 25% of the fund’s net assets in issuers located in the same state. The fund may hold up to 15% of its net assets in illiquid or thinly traded securities, which may include securities that are subject to resale restrictions such as those issued pursuant to Rule 144A of the Securities Act of 1933, as amended. The fund may invest in securities that do not produce immediate cash income, such as zero coupon securities and securities that are in payment default. The fund invests at least 80% of its net assets in investment grade municipal securities, as determined by a nationally recognized rating organization (NRSRO) (e.g., Baa3 or higher by Moody’s Investors Service, Inc. (Moody’s)) or if unrated, determined to be of comparable quality by the investment adviser. The fund may also invest in municipal securities that are less-than-investment grade, as determined by an NRSRO (e.g., Ba1 or lower by Moody’s) or by the investment adviser. In choosing securities, the fund’s investment adviser seeks to maximize current income by utilizing a flexible investment process that identifies opportunities in the municipal bond market of any maturity, duration and credit quality, including below investment grade securities. The investment adviser’s credit research department analyzes and monitors the securities that the fund owns or is considering buying. Under normal market conditions, the fund anticipates investing substantially in municipal bonds with remaining maturities of 5- to 30-years. The fund does not target a specific level of portfolio turnover as purchases and sales are made if the investment adviser determines the transactions will be advantageous to the fund. The fund may also invest in derivative instruments, principally futures contracts. The fund typically uses futures as a substitute for taking a position in the underlying asset or as a part of a strategy designed to reduce exposure to other risks. During unusual market conditions, the fund may invest entirely in taxable securities as a temporary defensive measure. When the fund engages in such activities, the fund would not be pursuing its investment strategy and, as a result, it may not achieve its investment objective.

To pursue its goal, the fund generally invests in securities that are included in the Bloomberg US Government/Credit 1-5 Year Index†. The index is a broad-based benchmark measuring the performance of U.S. dollar-denominated U.S. Treasury bonds, government related bonds (i.e., U.S. and non-U.S. agencies, sovereign, quasi-sovereign, supranational and local authority debt) and investment grade U.S. corporate bonds that have a remaining maturity of greater than or equal to one year and less than five years. To be eligible for inclusion in the index, securities must be fixed rate, non-convertible, U.S. dollar-denominated with at least $300 million or more of outstanding face value and have a remaining maturity greater than or equal to one year and less than five years. The index excludes certain types of securities, including, bonds with equity type features (e.g., warrants, convertibles and preferreds), tax-exempt municipal securities, inflation-linked bonds, floating rate issues, strips, private placements, U.S. dollar-denominated 25 and 50 par retail bonds, structured notes and pass-through certificates. The index is market capitalization weighted and the securities in the index are updated on the last business day of each month.

It is the fund’s policy that under normal circumstances it will invest at least 90% of its net assets (including, for this purpose, any borrowings for investment purposes) in securities included in the index. The fund will notify its shareholders at least 60 days before changing this policy. Under normal circumstances, the fund may invest up to 10% of its net assets in securities not included in its index. The principal types of these investments include those that the investment adviser believes will help the fund track the index, such as investments in (a) securities that are not represented in the index but the investment adviser anticipates will be added to the index; (b) high-quality liquid investments, such as securities issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, and obligations that are issued by private issuers; (c) other investment companies; and (d) derivatives, principally futures contracts. The fund may use futures contracts and other derivatives primarily to help manage interest rate exposure. The fund may also invest in cash and cash equivalents, including money market funds, and lend its securities to minimize the difference in performance that naturally exists between an index fund and its corresponding index.

Because it is not possible or practical to purchase all of the securities in the index, the fund’s investment adviser will seek to track the total return of the index by using sampling techniques.

†

Index ownership – Bloomberg® and Bloomberg US Government/Credit 1-5 Year Index are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (BISL), the administrator of the indices (collectively, “Bloomberg”). Bloomberg is not affiliated with Charles Schwab Investment Management, Inc., dba Schwab Asset Management, and Bloomberg does not approve, endorse, review, or recommend Schwab Short-Term Bond Index Fund. Bloomberg does not guarantee the timeliness, accurateness, or completeness of any data or information relating to Schwab Short-Term Bond Index Fund.

Sampling techniques involve investing in a limited number of index securities that, when taken together, are expected to perform similarly to the index as a whole. These techniques are based on a variety of factors, including interest rate and yield curve risk, maturity exposures, industry, sector and issuer weights, credit quality, and other risk factors and characteristics. The fund expects that its portfolio will hold less than the total number of securities in the index, but reserves the right to hold as many securities as it believes necessary to achieve the fund’s investment objective. The fund may sell securities that are represented in the index in anticipation of their removal from the index. In addition, the fund generally expects that its duration will closely correspond to the duration of the index, which as of August 31, 2024 was approximately 2.54 years.

The fund will concentrate its investments (i.e., hold more than 25% of its total assets) in a particular industry, group of industries or sector to approximately the same extent that its index is so concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities), and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry.

Prospectus [Line Items]

Strategy Narrative [Text Block]

To pursue its goal, the fund generally invests in securities that are included in the Bloomberg US Treasury Inflation-Linked Bond Index† (Series-L)SM. The index includes all publicly-issued treasury inflation-protected securities (TIPS) that have at least one year remaining to maturity, are rated investment grade and have $500 million or more of outstanding face value. The TIPS in the index must be denominated in U.S. dollars and must be fixed-rate and non-convertible. The index is market capitalization weighted and the TIPS in the index are updated on the last business day of each month. TIPS are publicly issued, dollar-denominated U.S. government securities issued by the U.S. Treasury that have principal and interest payments linked to an official inflation measure (as measured by the Consumer Price Index, or CPI) and their payments are supported by the full faith and credit of the United States.

It is the fund’s policy that, under normal circumstances, it will invest at least 90% of its net assets (including, for this purpose, any borrowings for investment purposes) in securities included in the index. The fund will notify its shareholders at least 60 days before changing this policy. The fund will generally seek to replicate the performance of the index by giving the same weight to a given security as the index does. However, when the investment adviser believes it is in the best interest of the fund, such as to avoid purchasing odd-lots (i.e., purchasing less than the usual number of shares traded for a security), for tax considerations, or to address liquidity considerations with respect to a security, the investment adviser may cause the fund’s weighting of a security to be more or less than the index’s weighting of the security. The fund may sell securities that are represented in the index in anticipation of their removal from the index.

Under normal circumstances, the fund may invest up to 10% of its net assets in securities not included in the index. The principal types of these investments include those that the investment adviser believes will help the fund track the index, such as investments in (a) securities that are not represented in the index but the investment adviser anticipates will be added to the index; (b) high-quality liquid investments, such as securities issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, and obligations that are issued by private issuers that are guaranteed as to principal or interest by the U.S. government, its agencies or instrumentalities, and (c) investment companies. The fund may also invest in cash and cash equivalents, including money market funds, enter into

†

Index ownership – Bloomberg® and Bloomberg US Treasury Inflation-Linked Bond Index are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (BISL), the administrator of the indices (collectively, “Bloomberg”). Bloomberg is not affiliated with Charles Schwab Investment Management, Inc.,dba Schwab Asset Management, and Bloomberg does not approve, endorse, review, or recommend Schwab Treasury Inflation Protected Securities Index Fund. Bloomberg does not guarantee the timeliness, accurateness, or completeness of any data or information relating to Schwab Treasury Inflation Protected Securities Index Fund.

repurchase agreements, and may lend its securities to minimize the difference in performance that naturally exists between an index fund and its corresponding index.

The investment adviser typically seeks to track the price and yield performance of the index by replicating the index. This means that the fund generally expects that it will hold the same securities as those included in the index. However, the investment adviser may use sampling techniques if the investment adviser believes such use will best help the fund to track the index or is otherwise in the best interest of the fund. Sampling techniques involve investing in a limited number of index securities that, when taken together, are expected to perform similarly to the index as a whole. These techniques are based on a variety of factors, including interest rate and yield curve risk, maturity exposures, and other risk factors and characteristics. When the fund uses sampling techniques, the fund generally expects that its yield, maturity and weighted average effective duration will be similar to those of the index.

Prospectus [Line Items]

Strategy Narrative [Text Block]

To pursue its goal, the fund generally invests in securities that are included in the Bloomberg US Aggregate Bond Index†. The index

is a broad-based benchmark measuring the performance of the U.S. investment grade, taxable bond market, including U.S. Treasuries, government-related and corporate bonds, mortgage pass-through securities, commercial mortgage-backed securities, and asset-backed securities that are publicly available for sale in the United States. To be eligible for inclusion in the index, a security must be fixed rate, non-convertible, U.S. dollar-denominated and have one or more years remaining to maturity. The index excludes certain types of securities, including, bonds with equity type features (e.g., warrants, convertibles and preferreds), tax-exempt municipal securities, inflation-linked bonds, floating-rate issues, strips, private placements, U.S. dollar-denominated 25 and 50 par retail bonds, structured notes and pass-through certificates. The index is market capitalization weighted and the securities in the index are updated on the last business day of each month.

It is the fund’s policy that under normal circumstances it will invest at least 90% of its net assets (including, for this purpose, any borrowings for investment purposes) in securities included in the index, including TBA transactions, as defined below. The fund will notify its shareholders at least 60 days before changing this policy. Under normal circumstances, the fund may invest up to 10% of its net assets in securities not included in its index. The principal types of these investments include those that the investment adviser believes will help the fund track the index, such as investments in (a) securities that are not represented in the index but the investment adviser anticipates will be added to the index; (b) high-quality liquid investments, such as securities issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, and obligations that are issued by private issuers; (c) other investment companies; and (d) derivatives, principally futures contracts. The fund may use futures contracts and other derivatives primarily to help manage interest rate exposure. The fund may also invest in cash and cash equivalents, including money market funds, and lend its securities to minimize the difference in performance that naturally exists between an index fund and its corresponding index.

Because it is not possible or practical to purchase all of the securities in the index, the fund’s investment adviser will seek to track the total return of the index by using sampling techniques. Sampling techniques involve investing in a limited number of index securities that, when taken together, are expected to perform similarly to the index as a whole. These techniques are based on a variety of factors, including interest rate and yield curve risk, maturity exposures, industry, sector and issuer weights, credit quality, and other risk factors and characteristics. The fund expects that its

†

Index ownership – Bloomberg® and Bloomberg US Aggregate Bond Index are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (BISL), the administrator of the indices (collectively, “Bloomberg”). Bloomberg is not affiliated with Charles Schwab Investment Management, Inc., dba Schwab Asset Management, and Bloomberg does not approve, endorse, review, or recommend Schwab U.S. Aggregate Bond Index Fund. Bloomberg does not guarantee the timeliness, accurateness, or completeness of any data or information relating to Schwab U.S. Aggregate Bond Index Fund.

portfolio will hold less than the total number of securities in the index, but reserves the right to hold as many securities as it believes necessary to achieve the fund’s investment objective. The fund may sell securities that are represented in the index in anticipation of their removal from the index. The fund generally expects that its duration will closely correspond to the duration of the index, which as of August 31, 2024, was approximately 6.08 years.

As of August 31, 2024, approximately 25.52% of the bonds represented in the index were U.S. fixed-rate agency mortgage pass-through securities. U.S. fixed-rate agency mortgage pass-through securities are securities issued by entities such as the Government National Mortgage Association (Ginnie Mae), the Federal National Mortgage Association (Fannie Mae), and the Federal Home Loan Mortgage Corporation (Freddie Mac) that are backed by pools of mortgages. Many transactions in fixed-rate mortgage pass-through securities occur through standardized contracts for future delivery in which the exact mortgage pools to be delivered are not specified until a few days prior to settlement, and are often referred to as “to-be-announced transactions” or “TBA transactions.” In a TBA transaction, the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to settlement date; however, it is not anticipated that the fund will receive the pools, but will instead participate in rolling TBA transactions. The fund anticipates that it may enter into such contracts on a regular basis. This may result in a significantly higher portfolio turnover for the fund than a typical index fund. The fund, pending settlement of such contracts, will invest its assets in high-quality liquid short-term instruments, including Treasury securities and shares of money market mutual funds. The fund will assume its pro rata share of the fees and expenses of any money market fund that it may invest in, in addition to the fund’s own fees and expenses.

The fund will concentrate its investments (i.e., hold more than 25% of its total assets) in a particular industry, group of industries or sector to approximately the same extent that its index is so concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities), and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry.

Prospectus [Line Items]

Strategy Narrative [Text Block]

To pursue its goal, the fund primarily invests in investment-grade municipal securities – those in the four highest credit rating categories (rated AAA to BBB- or the unrated equivalent as determined by the investment adviser). The fund normally invests at least 80% of its net assets (including, for this purpose, any borrowings for investment purposes) in municipal securities the interest from which is exempt from federal income tax, including the federal alternative minimum tax (AMT).

The fund may invest in fixed-, variable- or floating-rate securities from municipal issuers around the country and in U.S. territories and possessions. These may include general obligation issues, which typically are backed by the issuer’s ability to levy taxes, and revenue issues, which typically are backed by a stream of revenue from a given source, such as an electric utility or a public water system. The fund may invest more than 25% of its total assets in municipal securities financing similar projects, such as those relating to education, health care, transportation and utilities and may also invest in municipal notes. The fund’s securities may carry credit enhancements (such as bond insurance) or liquidity enhancements (such as a letter of credit), which are designed to provide incremental levels of creditworthiness or liquidity.

In choosing securities, the fund’s investment adviser seeks to maximize current income within the limits of the fund’s credit and maturity standards. The investment adviser’s credit research department analyzes and monitors the securities that the fund owns or is considering buying. The fund may invest up to 15% of its assets in below investment grade bonds (sometimes called junk bonds) that are rated, at the time of investment, at least B by at least one nationally recognized statistical rating organization or are the unrated equivalent as determined by the investment adviser. If a bond is downgraded below B or the unrated equivalent, the fund may continue to hold it unless the investment adviser determines the risk of holding the bond is unacceptable when compared to the bond’s total return potential. The investment adviser may adjust the fund’s holdings based on actual or anticipated changes in interest rates or credit quality.

The fund may also invest in derivative instruments, principally futures contracts. The fund typically uses futures as a substitute for taking a position in the underlying asset or as a part of a strategy designed to reduce exposure to other risks. During unusual market conditions, the fund may invest entirely in taxable securities and municipal securities whose interest is subject to federal income tax and the AMT as a temporary defensive measure. When the fund

engages in such activities, the fund would not be pursuing its investment strategy and, as a result, it may not achieve its investment objective.

Prospectus [Line Items]

Strategy Narrative [Text Block]

To pursue its goal, the fund primarily invests in investment-grade municipal securities – those in the four highest credit rating categories (rated AAA to BBB- or the unrated equivalent as determined by the investment adviser) from California issuers. The fund normally invests at least 80% of its net assets (including, for this purpose, any borrowings for investment purposes) in municipal securities the interest from which is exempt from federal and California personal income tax and federal alternative minimum tax (AMT). These securities may include those issued by issuers located outside of California, such as U.S. territories and possessions, or by their agencies, authorities, or instrumentalities.

The fund may invest in securities from municipal issuers in California and in U.S. territories and possessions. These may include general obligation issues, which typically are backed by the issuer’s ability to levy taxes, and revenue issues, which typically are backed by a stream of revenue from a given source, such as an electric utility or a public water system. The fund may invest more than 25% of its total assets in municipal securities financing similar projects, such as those relating to education, health care, transportation and utilities and may also invest in municipal notes. The fund’s securities may carry credit enhancements (such as bond insurance) or liquidity enhancements (such as a letter of credit), which are designed to provide incremental levels of creditworthiness or liquidity.

In choosing securities, the fund’s investment adviser seeks to maximize current income within the limits of the fund’s credit and maturity standards. The investment adviser’s credit research department analyzes and monitors the securities that the fund owns or is considering buying. The fund may invest up to 15% of its assets in below investment grade bonds (sometimes called junk bonds) that are rated, at the time of investment, at least B by at least one nationally recognized statistical rating organization or are the unrated equivalent as determined by the investment adviser. If a bond is downgraded below B or the unrated equivalent, the fund may continue to hold it unless the investment adviser determines the risk of holding the bond is unacceptable when compared to the bond’s total return potential. The investment adviser may adjust the fund’s holdings based on actual or anticipated changes in interest rates or credit quality.

The fund may also invest in derivative instruments, principally futures contracts. The fund typically uses futures as a substitute for taking a position in the underlying asset or as a part of a strategy designed to reduce exposure to other risks.

During unusual market conditions, the fund may invest entirely in taxable securities and municipal securities whose interest is subject to federal income tax and the AMT, and also California personal income tax, as a temporary defensive measure. When the fund engages in such activities, the fund would not be pursuing its investment strategy and, as a result, it may not achieve its investment objective.

Prospectus [Line Items]

Strategy Narrative [Text Block]

Under normal market conditions, the fund invests at least 80% of its net assets (including, for this purpose, any borrowings for investment purposes) in municipal securities that pay interest not subject to regular federal income tax. Some of these investments in municipal securities may pay interest that is not exempt from the federal alternative minimum tax (AMT). Municipal securities may include debt obligations of U.S. states, territories, counties, cities, political subdivisions, government agencies and instrumentalities. The fund also invests in non-governmental municipal issuers, including, but not limited to, healthcare organizations, corporate issuers of municipal debt, and various project finance bond issues. The fund primarily invests in general obligation and revenue obligation securities, including fixed and variable rate securities, municipal notes and private placements, auction-rate securities, variable rate demand notes, lease-backed obligations and certificates of participation.

The fund may from time to time invest temporarily up to 20% of its net assets in taxable securities of at least comparable quality to the municipal securities in which the Fund invests. The fund may also invest up to 25% of its net assets in municipal securities that are subject to the AMT. The fund has no policy limiting its investments in municipal securities whose issuers are located in the same state or territory. However, the fund currently intends to invest no more than 25% of the fund’s net assets in issuers located in the same state. The fund may hold up to 15% of its net assets in illiquid or thinly traded securities, which may include securities that are subject to resale restrictions such as those issued pursuant to Rule 144A of the Securities Act of 1933, as amended. The fund may invest in securities that do not produce immediate cash income, such as zero coupon securities and securities that are in payment default.

The fund invests at least 80% of its net assets in investment grade municipal securities, as determined by a nationally recognized rating organization (NRSRO) (e.g., Baa3 or higher by Moody’s Investors Service, Inc. (Moody’s)) or if unrated, determined to be of comparable quality by the investment adviser. The fund may also invest in municipal securities that are less-than-investment grade, as determined by an NRSRO (e.g., Ba1 or lower by Moody’s) or by the investment adviser.

In choosing securities, the fund’s investment adviser seeks to maximize current income by utilizing a flexible investment process that identifies opportunities in the municipal bond market of any maturity, duration and credit quality, including below investment grade securities. The investment adviser’s credit research department analyzes and monitors the securities that the fund owns or is considering buying.

Under normal market conditions, the fund anticipates investing substantially in municipal bonds with remaining maturities of 5- to 30-years. The fund does not target a specific level of portfolio turnover as purchases and sales are made if the investment adviser determines the transactions will be advantageous to the fund.

The fund may also invest in derivative instruments, principally futures contracts. The fund typically uses futures as a substitute for taking a position in the underlying asset or as a part of a strategy designed to reduce exposure to other risks. During unusual market conditions, the fund may invest entirely in taxable securities as a temporary defensive measure. When the fund engages in such activities, the fund would not be pursuing its investment strategy and, as a result, it may not achieve its investment objective.