Label

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Value

Prospectus [Line Items]

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Document Type

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497

Document Period End Date

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Dec. 31, 2020

Registrant Name

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Putnam Variable Trust

Entity Central Index Key

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0000822671

Entity Inv Company Type

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N-1A

Amendment Flag

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false

Putnam VT Sustainable Future Fund

Prospectus [Line Items]

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Strategy [Heading]

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Investments

Strategy Narrative [Text Block]

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We invest mainly in common stocks of U.S. companies of any size, with a focus on companies whose products and services we believe provide solutions that directly contribute to sustainable social, environmental and economic development (Impact Companies). Stocks of this type of company are typically, but not always, considered to be growth stocks. Growth stocks are stocks of companies whose revenues, earnings, or cash flows are expected to grow faster than those of similar firms, and whose business growth and other characteristics may lead to an increase in stock price. We may consider, among other factors, a company’s impact on sustainable environmental, social and economic development (as described below), valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We may also invest in non-U.S. companies.

Our approach to sustainable investing incorporates fundamental research together with consideration of sustainable environmental, social and economic development impact. We believe that companies whose products and services produce positive environmental, social and economic development impact also often demonstrate potential for strong financial growth. Under normal circumstances, the fund invests at least 80% of the value of its net assets in securities that meet our sustainability criteria. These criteria are based on a proprietary sustainability solutions map that links to the United Nations Sustainable Development Goals (SDGs). In applying these criteria, we will assign each company a proprietary environmental, social and/or corporate governance (ESG) rating ranging from 1 to 4 (1 indicating the highest (best) ESG rating and 4 indicating the lowest (worst) ESG rating). In order to meet our sustainability criteria for purposes of this investment policy, a company must be rated 2 or 1 by us. This policy is non-fundamental and may be changed only after 60 days’ notice to shareholders. In selecting each investment, we consider the extent to which a company’s products or services may provide solutions to forward-looking sustainability needs, creating positive impact in environmental, social and economic development areas. Environmental impacts may include, for example, reduction of carbon emissions and improved water quality. Social impacts may include, for example, improvements in employee well-being, supplier standards, or access to products, information, or security. Economic development impacts may include, for example, stakeholder analysis and shared value approaches to business practices, access to economic opportunity, or improvements in operational effectiveness or efficiency.

Risk [Heading]

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• The seventh paragraph of the sub-section Risks in the section Fund summary – Investments, risks, and performance is deleted in its entirety and replaced with the following:

Risk Narrative [Text Block]

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Investing with a focus on Impact Companies, whose products and services may provide solutions that directly impact sustainable environmental, social and economic development, may result in the fund investing in certain types of companies, industries or sectors that the market may not favor. In evaluating an investment opportunity, we may make investment decisions based on information and data that is incomplete or inaccurate. Sustainability and ESG factors are not uniformly defined and applying such factors involves subjective assessments. Sustainability and ESG scorings and assessments of issuers can vary across third-party data providers and may change over time. In addition, a company’s business practices, products or services may change over time. As a result of these possibilities, among others, the fund may temporarily hold securities that are inconsistent with the fund’s sustainable investment criteria. Regulatory changes or interpretations regarding the definitions and/or use of ESG or other sustainability criteria could have a material adverse effect on the fund’s ability to invest in accordance with its investment policies and/or achieve its investment objective, as well as the ability of certain classes of investors to invest in funds, such as the fund, whose strategies include ESG or other sustainability criteria.