Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	BLACKROCK VARIABLE SERIES FUNDS, INC. BlackRock Advantage Large Cap Value V.I. Fund BlackRock Basic Value V.I. Fund BlackRock Equity Dividend V.I. Fund BlackRock Large Cap Focus Growth V.I. Fund (the “Funds”) Supplement dated February 28, 2025 to the Summary Prospectuses and Prospectuses of the Funds, each dated May 1, 2024, as supplemented to date On September 18, 2024 with respect to BlackRock Advantage Large Cap Value V.I. Fund, BlackRock Basic Value V.I. Fund and BlackRock Large Cap Focus Growth V.I. Fund and November 19, 2024 with respect to BlackRock Equity Dividend V.I. Fund, the Board of Directors of BlackRock Variable Series Funds, Inc. approved certain changes to the Funds’ investment strategies in order to satisfy new requirements pursuant to the recent amendments to Rule 35d‑1 under the Investment Company Act of 1940 (the “Names Rule”). These changes are expected to become effective on May 1, 2025. Accordingly, effective on May 1, 2025, the following changes are made to the Funds’ Summary Prospectuses and Prospectuses, as applicable: BlackRock Advantage Large Cap Value V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Advantage Large Cap Value V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following: Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap value equity securities of U.S. issuers and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap value equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Value Index (the “Russell 1000 Value Index”) and (ii) are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Value Indices. The Russell 1000 Value Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund primarily seeks to buy common stock and may also invest in preferred stock. The Fund may also purchase convertible securities. From time to time, the Fund may invest in shares of companies through “new issues” or initial public offerings (“IPOs”). The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps, some of which may be referred to as contracts for difference) and forward contracts, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a currency or an index, including but not limited to the Value Indices. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund’s assets. The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities. The Fund seeks to pursue its investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the portfolio by integrating its investment insights with the model-based optimization process. BlackRock Basic Value V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of each Fund” and the sections of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Basic Value V.I. Fund — Principal Investment Strategies of the Fund” and “Details About the Fund — How the Fund Invests — Principal Investment Strategies” are deleted in their entirety and replaced with the following: Under normal circumstances, the Fund seeks to invest at least 80% of its net assets plus the amount of any borrowings for investment purposes in value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, value equity securities are equity securities that are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. Value securities are generally considered to be those with prices less than Fund management believes they are worth. The Fund tries to achieve its objectives by investing in a diversified portfolio consisting primarily of equity securities, which includes common stock, preferred stock, or securities or other instruments whose price is linked to the value of common stock. The Fund may also purchase convertible securities. Fund management places particular emphasis on companies with below average price/earnings ratios that may pay above average dividends. The Fund invests primarily in common stock of U.S. companies, but the Fund may invest up to 25% of its total assets in the securities of foreign companies. The Fund focuses primarily on companies with market capitalizations of over $5 billion. BlackRock Equity Dividend V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Equity Dividend V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following: The Fund seeks to achieve its objective by investing primarily in a diversified portfolio of equity securities. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in dividend-paying equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. Equity securities include common stock, preferred stock or securities or other instruments whose price is linked to the value of common stock. For purposes of the Fund’s 80% policy, dividend-paying equity securities are securities of companies that pay out a portion of its profits to shareholders of such securities on a periodic basis. The Fund may invest up to 25% of its total assets in securities of foreign issuers. The Fund may invest in securities from any country. The Fund may invest in securities denominated in both U.S. dollars and non‑U.S. dollar currencies. The Fund may invest in the securities of foreign issuers in the form of American Depositary Receipts, European Depositary Receipts or other securities convertible into securities of foreign issuers. BlackRock chooses investments for the Fund that it believes will both increase in value over the long term and provide current income, focusing on investments that will do both instead of those that will favor current income over capital appreciation. BlackRock Large Cap Focus Growth V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Large Cap Focus Growth V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following: Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap growth equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap growth equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Growth Index (the “Russell 1000 Growth Index”) and (ii) are included within at least one growth index, as determined by BlackRock (the “Growth Indices”). Currently, such Growth Indices are the Russell 3000^® Growth Index, the S&P Composite 1500^® Growth Index and the MSCI World Growth Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Growth Indices. The Russell 1000 Growth Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund is a growth fund that invests primarily in common stock. The Fund may also purchase convertible securities. The Fund may invest without limitation in the securities of foreign companies in the form of American Depositary Receipts (“ADRs”). In addition to ADRs, the Fund may also invest up to 20% of its total assets in other forms of securities of foreign companies, including European Depositary Receipts, which are receipts typically issued in Europe evidencing an ownership arrangement with the foreign company or other securities of foreign companies.
BlackRock Advantage Large Cap Value V.I. Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	BLACKROCK VARIABLE SERIES FUNDS, INC. BlackRock Advantage Large Cap Value V.I. Fund (the “Funds”) Supplement dated February 28, 2025 to the Summary Prospectuses and Prospectuses of the Funds, each dated May 1, 2024, as supplemented to date On September 18, 2024 with respect to BlackRock Advantage Large Cap Value V.I. Fund, BlackRock Basic Value V.I. Fund and BlackRock Large Cap Focus Growth V.I. Fund and November 19, 2024 with respect to BlackRock Equity Dividend V.I. Fund, the Board of Directors of BlackRock Variable Series Funds, Inc. approved certain changes to the Funds’ investment strategies in order to satisfy new requirements pursuant to the recent amendments to Rule 35d‑1 under the Investment Company Act of 1940 (the “Names Rule”). These changes are expected to become effective on May 1, 2025. Accordingly, effective on May 1, 2025, the following changes are made to the Funds’ Summary Prospectuses and Prospectuses, as applicable: BlackRock Advantage Large Cap Value V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Advantage Large Cap Value V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following: Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap value equity securities of U.S. issuers and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap value equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Value Index (the “Russell 1000 Value Index”) and (ii) are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Value Indices. The Russell 1000 Value Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund primarily seeks to buy common stock and may also invest in preferred stock. The Fund may also purchase convertible securities. From time to time, the Fund may invest in shares of companies through “new issues” or initial public offerings (“IPOs”). The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps, some of which may be referred to as contracts for difference) and forward contracts, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a currency or an index, including but not limited to the Value Indices. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund’s assets. The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities. The Fund seeks to pursue its investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the portfolio by integrating its investment insights with the model-based optimization process.
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap value equity securities of U.S. issuers and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap value equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Value Index (the “Russell 1000 Value Index”) and (ii) are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Value Indices. The Russell 1000 Value Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund primarily seeks to buy common stock and may also invest in preferred stock. The Fund may also purchase convertible securities. From time to time, the Fund may invest in shares of companies through “new issues” or initial public offerings (“IPOs”). The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps, some of which may be referred to as contracts for difference) and forward contracts, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a currency or an index, including but not limited to the Value Indices. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund’s assets. The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities. The Fund seeks to pursue its investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the portfolio by integrating its investment insights with the model-based optimization process.
BlackRock Basic Value V.I. Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	BLACKROCK VARIABLE SERIES FUNDS, INC. BlackRock Basic Value V.I. Fund (the “Funds”) Supplement dated February 28, 2025 to the Summary Prospectuses and Prospectuses of the Funds, each dated May 1, 2024, as supplemented to date On September 18, 2024 with respect to BlackRock Advantage Large Cap Value V.I. Fund, BlackRock Basic Value V.I. Fund and BlackRock Large Cap Focus Growth V.I. Fund and November 19, 2024 with respect to BlackRock Equity Dividend V.I. Fund, the Board of Directors of BlackRock Variable Series Funds, Inc. approved certain changes to the Funds’ investment strategies in order to satisfy new requirements pursuant to the recent amendments to Rule 35d‑1 under the Investment Company Act of 1940 (the “Names Rule”). These changes are expected to become effective on May 1, 2025. Accordingly, effective on May 1, 2025, the following changes are made to the Funds’ Summary Prospectuses and Prospectuses, as applicable: BlackRock Basic Value V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of each Fund” and the sections of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Basic Value V.I. Fund — Principal Investment Strategies of the Fund” and “Details About the Fund — How the Fund Invests — Principal Investment Strategies” are deleted in their entirety and replaced with the following: Under normal circumstances, the Fund seeks to invest at least 80% of its net assets plus the amount of any borrowings for investment purposes in value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, value equity securities are equity securities that are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. Value securities are generally considered to be those with prices less than Fund management believes they are worth. The Fund tries to achieve its objectives by investing in a diversified portfolio consisting primarily of equity securities, which includes common stock, preferred stock, or securities or other instruments whose price is linked to the value of common stock. The Fund may also purchase convertible securities. Fund management places particular emphasis on companies with below average price/earnings ratios that may pay above average dividends. The Fund invests primarily in common stock of U.S. companies, but the Fund may invest up to 25% of its total assets in the securities of foreign companies. The Fund focuses primarily on companies with market capitalizations of over $5 billion.
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund seeks to invest at least 80% of its net assets plus the amount of any borrowings for investment purposes in value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, value equity securities are equity securities that are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. Value securities are generally considered to be those with prices less than Fund management believes they are worth. The Fund tries to achieve its objectives by investing in a diversified portfolio consisting primarily of equity securities, which includes common stock, preferred stock, or securities or other instruments whose price is linked to the value of common stock. The Fund may also purchase convertible securities. Fund management places particular emphasis on companies with below average price/earnings ratios that may pay above average dividends. The Fund invests primarily in common stock of U.S. companies, but the Fund may invest up to 25% of its total assets in the securities of foreign companies. The Fund focuses primarily on companies with market capitalizations of over $5 billion.
BlackRock Equity Dividend V.I. Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	BLACKROCK VARIABLE SERIES FUNDS, INC. BlackRock Equity Dividend V.I. Fund (the “Funds”) Supplement dated February 28, 2025 to the Summary Prospectuses and Prospectuses of the Funds, each dated May 1, 2024, as supplemented to date On September 18, 2024 with respect to BlackRock Advantage Large Cap Value V.I. Fund, BlackRock Basic Value V.I. Fund and BlackRock Large Cap Focus Growth V.I. Fund and November 19, 2024 with respect to BlackRock Equity Dividend V.I. Fund, the Board of Directors of BlackRock Variable Series Funds, Inc. approved certain changes to the Funds’ investment strategies in order to satisfy new requirements pursuant to the recent amendments to Rule 35d‑1 under the Investment Company Act of 1940 (the “Names Rule”). These changes are expected to become effective on May 1, 2025. Accordingly, effective on May 1, 2025, the following changes are made to the Funds’ Summary Prospectuses and Prospectuses, as applicable: BlackRock Equity Dividend V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Equity Dividend V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following: The Fund seeks to achieve its objective by investing primarily in a diversified portfolio of equity securities. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in dividend-paying equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. Equity securities include common stock, preferred stock or securities or other instruments whose price is linked to the value of common stock. For purposes of the Fund’s 80% policy, dividend-paying equity securities are securities of companies that pay out a portion of its profits to shareholders of such securities on a periodic basis. The Fund may invest up to 25% of its total assets in securities of foreign issuers. The Fund may invest in securities from any country. The Fund may invest in securities denominated in both U.S. dollars and non‑U.S. dollar currencies. The Fund may invest in the securities of foreign issuers in the form of American Depositary Receipts, European Depositary Receipts or other securities convertible into securities of foreign issuers. BlackRock chooses investments for the Fund that it believes will both increase in value over the long term and provide current income, focusing on investments that will do both instead of those that will favor current income over capital appreciation.
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund seeks to achieve its objective by investing primarily in a diversified portfolio of equity securities. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in dividend-paying equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. Equity securities include common stock, preferred stock or securities or other instruments whose price is linked to the value of common stock. For purposes of the Fund’s 80% policy, dividend-paying equity securities are securities of companies that pay out a portion of its profits to shareholders of such securities on a periodic basis. The Fund may invest up to 25% of its total assets in securities of foreign issuers. The Fund may invest in securities from any country. The Fund may invest in securities denominated in both U.S. dollars and non‑U.S. dollar currencies. The Fund may invest in the securities of foreign issuers in the form of American Depositary Receipts, European Depositary Receipts or other securities convertible into securities of foreign issuers. BlackRock chooses investments for the Fund that it believes will both increase in value over the long term and provide current income, focusing on investments that will do both instead of those that will favor current income over capital appreciation.
BlackRock Large Cap Focus Growth V.I. Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	BLACKROCK VARIABLE SERIES FUNDS, INC. BlackRock Large Cap Focus Growth V.I. Fund (the “Funds”) Supplement dated February 28, 2025 to the Summary Prospectuses and Prospectuses of the Funds, each dated May 1, 2024, as supplemented to date On September 18, 2024 with respect to BlackRock Advantage Large Cap Value V.I. Fund, BlackRock Basic Value V.I. Fund and BlackRock Large Cap Focus Growth V.I. Fund and November 19, 2024 with respect to BlackRock Equity Dividend V.I. Fund, the Board of Directors of BlackRock Variable Series Funds, Inc. approved certain changes to the Funds’ investment strategies in order to satisfy new requirements pursuant to the recent amendments to Rule 35d‑1 under the Investment Company Act of 1940 (the “Names Rule”). These changes are expected to become effective on May 1, 2025. Accordingly, effective on May 1, 2025, the following changes are made to the Funds’ Summary Prospectuses and Prospectuses, as applicable: BlackRock Large Cap Focus Growth V.I. Fund The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Large Cap Focus Growth V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following: Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap growth equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap growth equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Growth Index (the “Russell 1000 Growth Index”) and (ii) are included within at least one growth index, as determined by BlackRock (the “Growth Indices”). Currently, such Growth Indices are the Russell 3000^® Growth Index, the S&P Composite 1500^® Growth Index and the MSCI World Growth Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Growth Indices. The Russell 1000 Growth Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund is a growth fund that invests primarily in common stock. The Fund may also purchase convertible securities. The Fund may invest without limitation in the securities of foreign companies in the form of American Depositary Receipts (“ADRs”). In addition to ADRs, the Fund may also invest up to 20% of its total assets in other forms of securities of foreign companies, including European Depositary Receipts, which are receipts typically issued in Europe evidencing an ownership arrangement with the foreign company or other securities of foreign companies.
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap growth equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap growth equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Growth Index (the “Russell 1000 Growth Index”) and (ii) are included within at least one growth index, as determined by BlackRock (the “Growth Indices”). Currently, such Growth Indices are the Russell 3000^® Growth Index, the S&P Composite 1500^® Growth Index and the MSCI World Growth Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Growth Indices. The Russell 1000 Growth Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund is a growth fund that invests primarily in common stock. The Fund may also purchase convertible securities. The Fund may invest without limitation in the securities of foreign companies in the form of American Depositary Receipts (“ADRs”). In addition to ADRs, the Fund may also invest up to 20% of its total assets in other forms of securities of foreign companies, including European Depositary Receipts, which are receipts typically issued in Europe evidencing an ownership arrangement with the foreign company or other securities of foreign companies.

rr_SupplementToProspectusTextBlock

BLACKROCK VARIABLE SERIES FUNDS, INC.

BlackRock Advantage Large Cap Value V.I. Fund

BlackRock Basic Value V.I. Fund

BlackRock Equity Dividend V.I. Fund

BlackRock Large Cap Focus Growth V.I. Fund

(the “Funds”)

Supplement dated February 28, 2025 to the Summary Prospectuses and Prospectuses of the Funds, each dated May 1, 2024, as supplemented to date

On September 18, 2024 with respect to BlackRock Advantage Large Cap Value V.I. Fund, BlackRock Basic Value V.I. Fund and BlackRock Large Cap Focus Growth V.I. Fund and November 19, 2024 with respect to BlackRock Equity Dividend V.I. Fund, the Board of Directors of BlackRock Variable Series Funds, Inc. approved certain changes to the Funds’ investment strategies in order to satisfy new requirements pursuant to the recent amendments to Rule 35d‑1 under the Investment Company Act of 1940 (the “Names Rule”). These changes are expected to become effective on May 1, 2025.

Accordingly, effective on May 1, 2025, the following changes are made to the Funds’ Summary Prospectuses and Prospectuses, as applicable:

BlackRock Advantage Large Cap Value V.I. Fund

The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Advantage Large Cap Value V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following:

Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap value equity securities of U.S. issuers and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap value equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Value Index (the “Russell 1000 Value Index”) and (ii) are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Value Indices. The Russell 1000 Value Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund primarily seeks to buy common stock and may also invest in preferred stock. The Fund may also purchase convertible securities. From time to time, the Fund may invest in shares of companies through “new issues” or initial public offerings (“IPOs”).

The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps, some of which may be referred to as contracts for difference) and forward contracts, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a currency or an index, including but not limited to the Value Indices. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund’s assets.

The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities.

The Fund seeks to pursue its investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the portfolio by integrating its investment insights with the model-based optimization process.

BlackRock Basic Value V.I. Fund

The section of the Summary Prospectus entitled “Principal Investment Strategies of each Fund” and the sections of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Basic Value V.I. Fund — Principal Investment Strategies of the Fund” and “Details About the Fund — How the Fund Invests — Principal Investment Strategies” are deleted in their entirety and replaced with the following:

Under normal circumstances, the Fund seeks to invest at least 80% of its net assets plus the amount of any borrowings for investment purposes in value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, value equity securities are equity securities that are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index.

Value securities are generally considered to be those with prices less than Fund management believes they are worth. The Fund tries to achieve its objectives by investing in a diversified portfolio consisting primarily of equity securities, which includes common stock, preferred stock, or securities or other instruments whose price is linked to the value of common stock. The Fund may also purchase convertible securities. Fund management places particular emphasis on companies with below average price/earnings ratios that may pay above average dividends. The Fund invests primarily in common stock of U.S. companies, but the Fund may invest up to 25% of its total assets in the securities of foreign companies. The Fund focuses primarily on companies with market capitalizations of over $5 billion.

BlackRock Equity Dividend V.I. Fund

The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Equity Dividend V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following:

The Fund seeks to achieve its objective by investing primarily in a diversified portfolio of equity securities. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in dividend-paying equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. Equity securities include common stock, preferred stock or securities or other instruments whose price is linked to the value of common stock. For purposes of the Fund’s 80% policy, dividend-paying equity securities are securities of companies that pay out a portion of its profits to shareholders of such securities on a periodic basis.

The Fund may invest up to 25% of its total assets in securities of foreign issuers. The Fund may invest in securities from any country. The Fund may invest in securities denominated in both U.S. dollars and non‑U.S. dollar currencies. The Fund may invest in the securities of foreign issuers in the form of American Depositary Receipts, European Depositary Receipts or other securities convertible into securities of foreign issuers.

BlackRock chooses investments for the Fund that it believes will both increase in value over the long term and provide current income, focusing on investments that will do both instead of those that will favor current income over capital appreciation.

BlackRock Large Cap Focus Growth V.I. Fund

The section of the Summary Prospectus entitled “Principal Investment Strategies of the Fund” and the section of the Prospectus entitled “Fund Overview — Key Facts About BlackRock Large Cap Focus Growth V.I. Fund — Principal Investment Strategies of the Fund” are deleted in their entirety and replaced with the following:

Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap growth equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap growth equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Growth Index (the “Russell 1000 Growth Index”) and (ii) are included within at least one growth index, as determined by BlackRock (the “Growth Indices”). Currently, such Growth Indices are the Russell 3000^® Growth Index, the S&P Composite 1500^® Growth Index and the MSCI World Growth Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Growth Indices. The Russell 1000 Growth Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation.

The Fund is a growth fund that invests primarily in common stock. The Fund may also purchase convertible securities. The Fund may invest without limitation in the securities of foreign companies in the form of American Depositary Receipts (“ADRs”).

In addition to ADRs, the Fund may also invest up to 20% of its total assets in other forms of securities of foreign companies, including European Depositary Receipts, which are receipts typically issued in Europe evidencing an ownership arrangement with the foreign company or other securities of foreign companies.

Risk/Return:

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Strategy Narrative [Text Block]

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Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap value equity securities of U.S. issuers and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap value equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Value Index (the “Russell 1000 Value Index”) and (ii) are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Value Indices. The Russell 1000 Value Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund primarily seeks to buy common stock and may also invest in preferred stock. The Fund may also purchase convertible securities. From time to time, the Fund may invest in shares of companies through “new issues” or initial public offerings (“IPOs”).

The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps, some of which may be referred to as contracts for difference) and forward contracts, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a currency or an index, including but not limited to the Value Indices. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund’s assets.

The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities.

The Fund seeks to pursue its investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the portfolio by integrating its investment insights with the model-based optimization process.

Risk/Return:

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Strategy Narrative [Text Block]

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Under normal circumstances, the Fund seeks to invest at least 80% of its net assets plus the amount of any borrowings for investment purposes in value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, value equity securities are equity securities that are included within at least one value index, as determined by BlackRock (the “Value Indices”). Currently, such Value Indices are the Russell 3000^® Value Index, the S&P Composite 1500^® Value Index and the MSCI World Value Index.

Value securities are generally considered to be those with prices less than Fund management believes they are worth. The Fund tries to achieve its objectives by investing in a diversified portfolio consisting primarily of equity securities, which includes common stock, preferred stock, or securities or other instruments whose price is linked to the value of common stock. The Fund may also purchase convertible securities. Fund management places particular emphasis on companies with below average price/earnings ratios that may pay above average dividends. The Fund invests primarily in common stock of U.S. companies, but the Fund may invest up to 25% of its total assets in the securities of foreign companies. The Fund focuses primarily on companies with market capitalizations of over $5 billion.

Risk/Return:

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Strategy Narrative [Text Block]

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The Fund seeks to achieve its objective by investing primarily in a diversified portfolio of equity securities. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in dividend-paying equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. Equity securities include common stock, preferred stock or securities or other instruments whose price is linked to the value of common stock. For purposes of the Fund’s 80% policy, dividend-paying equity securities are securities of companies that pay out a portion of its profits to shareholders of such securities on a periodic basis.

The Fund may invest up to 25% of its total assets in securities of foreign issuers. The Fund may invest in securities from any country. The Fund may invest in securities denominated in both U.S. dollars and non‑U.S. dollar currencies. The Fund may invest in the securities of foreign issuers in the form of American Depositary Receipts, European Depositary Receipts or other securities convertible into securities of foreign issuers.

BlackRock chooses investments for the Fund that it believes will both increase in value over the long term and provide current income, focusing on investments that will do both instead of those that will favor current income over capital appreciation.

Risk/Return:

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Strategy Narrative [Text Block]

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Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap growth equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. For purposes of the Fund’s 80% policy, large cap growth equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 1000^® Growth Index (the “Russell 1000 Growth Index”) and (ii) are included within at least one growth index, as determined by BlackRock (the “Growth Indices”). Currently, such Growth Indices are the Russell 3000^® Growth Index, the S&P Composite 1500^® Growth Index and the MSCI World Growth Index. The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Growth Indices. The Russell 1000 Growth Index is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation.

The Fund is a growth fund that invests primarily in common stock. The Fund may also purchase convertible securities. The Fund may invest without limitation in the securities of foreign companies in the form of American Depositary Receipts (“ADRs”).

In addition to ADRs, the Fund may also invest up to 20% of its total assets in other forms of securities of foreign companies, including European Depositary Receipts, which are receipts typically issued in Europe evidencing an ownership arrangement with the foreign company or other securities of foreign companies.