The following table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Portfolio. The table below does not reflect any fees and expenses associated with variable life insurance contracts and variable annuity certificates and contracts (“Contracts”), which would increase overall fees and expenses. See the Contract prospectus for a description of those fees and expenses.

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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

Fee Waiver or Reimbursement over Assets, Date of Termination

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April 30, 2023

Portfolio Turnover [Heading]

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PORTFOLIO TURNOVER

Portfolio Turnover [Text Block]

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The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Portfolio’s performance. Because the Portfolio had not commenced investment operations as of the date of this Prospectus, it does not have portfolio turnover information for the prior fiscal year to report.

Other Expenses, New Fund, Based on Estimates [Text]

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Based on estimated amounts for the current fiscal year.

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other portfolios. The Example assumes that you invest $10,000 in the Portfolio for the periods indicated, that your investment has a 5% return each year, that the Portfolio’s operating expenses remain the same, and that the Expense Limitation Arrangement is not renewed. This Example does not reflect any Contract-related fees and expenses including redemption fees (if any) at the Contract level. If such fees and expenses were reflected, the total expenses would be higher. Although your actual costs may be higher or lower, based on these assumptions, whether you redeem or hold your shares, your costs would be:

Strategy [Heading]

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INVESTMENTS, RISKS, AND PERFORMANCE Principal Investment Strategy:

Strategy Narrative [Text Block]

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Under normal conditions, the Portfolio invests at least 80% of its net assets, plus borrowings for investment purposes, in equity securities of U.S. companies. The Portfolio’s Sub‑Adviser employs a combination of “top‑down” and “bottom‑up” investment processes with the goal of identifying, based on its internal research and analysis, the most attractive U.S. companies that fit into sustainable investment themes. For this Portfolio, a “U.S. company” is any company that is organized in or has substantial business activities in the United States.

Through its “top down” process, the Sub‑Adviser identifies sustainable investment themes that are broadly consistent with achieving the United Nations Sustainable Development Goals (“SDGs”), which generally address challenges relating to economic prosperity, environmental sustainability, and social inclusion. The Sub‑Adviser currently focuses on three

primary investment themes — climate, health, and empowerment — but the focus may change over time based on the Sub‑Adviser’s research. Within each of these primary investment themes, the Sub‑Adviser identifies sub‑themes to further determine the investment opportunities that meet the Portfolio’s criteria for sustainable investments. A company that derives at least 25% of its total revenues from activities that the Sub‑Adviser believes are consistent with the achievement of the SDGs meets such criteria, although many of the companies in which the Portfolio invests derive a much greater portion of their revenues from such activities. Examples of sub‑themes within climate currently include cleaner energy and resource efficiency, sanitation and recycling, and sustainable transportation. Examples of sub‑themes within health currently include access to quality care, food security and clean water, medical innovation, and well being. Examples of sub‑themes within empowerment currently include education and employment services, financial security and inclusion, information and communication technologies, and sustainable infrastructure. These primary investment themes and sub‑themes are subject to change.

After the Sub‑Adviser identifies a target universe of companies that meet the Portfolio’s criteria for sustainable investments, the Sub‑Adviser engages in a detailed, “bottom‑up” fundamental analysis of individual companies. The analysis focuses on a company’s financial strength and prospective earnings growth, quality of management and whether management is aligned with stakeholders, and valuation, and incorporates an evaluation of a company’s opportunities and risks relating to environmental, social and corporate governance (“ESG”) factors. ESG factors, which can vary across companies and industries, may include environmental impact, corporate governance, ethical business practices, diversity and employee practices, product safety, supply chain management, and community impact. While the Sub‑Adviser emphasizes positive selection criteria over broad-based negative screens in assessing a company’s exposure to ESG factors, the Portfolio will not invest in companies that derive revenue from direct involvement in alcohol, coal, gambling, pornography, prisons, tobacco or weapons. The Portfolio seeks to own a portfolio of high quality companies whose products and services contribute to the achievement of one or more of the SDGs.

The Portfolio generally invests in approximately 30 to 60 companies. The Portfolio may invest in companies of any size; however, it invests primarily in mid‑ to large-capitalization companies. For this Portfolio, issuers with market capitalization between $2 billion and $5 billion are considered mid‑capitalization while those above $5 billion are considered large-capitalization.

The Portfolio may invest up to 10% of its assets in foreign securities, typically by investing in American Depositary Receipts and Global Depositary Receipts.

The Portfolio also may lend its portfolio securities to earn additional income.

Risk [Heading]

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Principal Risks:

Risk Narrative [Text Block]

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An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Portfolio. There can be no assurance that the Portfolio will achieve its investment objective.

The following risks can negatively affect the Portfolio’s performance. The most significant risks as of the date of this Prospectus are listed first, followed by additional risks in alphabetical order.

Market Risk: The Portfolio is subject to the risk that the securities markets will move down, sometimes rapidly and unpredictably, based on overall economic conditions and other factors, which may negatively affect Portfolio performance. Securities markets also may experience long periods of decline in value. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Changes in the financial condition of a single issuer can impact a market as a whole. Geopolitical events, including terrorism, tensions or open conflict between nations, or political or economic dysfunction within some nations that are global economic powers, may lead to instability in world economies and markets, may lead to increased market volatility, and may have adverse long-term effects. Events such as environmental and natural disasters, public health crises (such as epidemics and pandemics), social unrest, and cybersecurity incidents, and governments’ reactions to such events, could cause uncertainty in the markets and may adversely affect the performance of the global economy. Impacts from climate change may include significant risks to global financial assets and economic growth. In addition, markets and market-participants are increasingly reliant on information data systems. Inaccurate data, software or other technology malfunctions, programming inaccuracies, unauthorized use or access, and similar circumstances may impair the performance of these systems and may have an adverse impact upon a single issuer, a group of issuers, or the market at‑large.

Equity Risk: In general, the values of stocks and other equity securities fluctuate, and sometimes widely fluctuate, in response to changes in a company’s financial condition as well as general market, economic and political conditions and other factors.

ESG Considerations Risk: Consideration of ESG factors and sustainability criteria in the investment process may limit the types and number of investment opportunities available to the Portfolio, and therefore carries the risk that, under certain market conditions, the Portfolio may underperform funds that do not consider ESG factors or sustainability criteria. The integration of ESG and sustainability considerations may affect the Portfolio’s exposure to certain sectors or types of investments and may impact the Portfolio’s relative investment performance depending on whether such sectors or investments are in or out of favor in the market. Furthermore, “sustainability” is not a uniformly defined characteristic, and the Portfolio’s sustainability criteria may differ from those used by other funds. A company’s ESG performance or the Sub‑Adviser’s assessment of a company’s ESG performance may change over time, which could cause the Portfolio to temporarily hold securities that do not comply with the Portfolio’s criteria for sustainable investments. In evaluating a company, the Sub‑Adviser is dependent upon information or data that may be incomplete, inaccurate or unavailable, which could cause the Sub‑Adviser to incorrectly assess a company’s ESG performance. Successful application of the Portfolio’s ESG and sustainability considerations will depend on the Sub‑Adviser’s skill in properly identifying and analyzing material ESG and sustainability issues. In addition, it is possible that a company that derives at least 25% of its total revenues from activities that the Sub‑Adviser believes are consistent with the achievement of the SDGs may have some exposure to product lines or businesses that do not meet the SDGs.

Large‑Cap Company Risk: Larger more established companies may be unable to respond quickly to new competitive challenges such as changes in technology and consumer tastes, which may lead to a decline in their market price. Many larger companies also may not be able to attain the high growth rate of successful smaller companies, especially during extended periods of economic expansion.

Mid‑Cap Company Risk: Mid‑cap companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies, all of which can negatively affect their value.

Portfolio Management Risk: The Portfolio is subject to the risk that strategies used by an investment manager and its securities selections fail to produce the intended results. An investment manager’s judgments or decisions about the quality, relative yield or value of, or market trends affecting, a particular security or issuer, industry, sector, region or market segment, or about the economy or interest rates, may be incorrect or otherwise may not produce the intended results, which may result in losses to the Portfolio. In addition, many processes used in Portfolio management, including security selection, rely, in whole or in part, on the use of various technologies. The Portfolio may suffer losses if there are imperfections, errors or limitations in the quantitative, analytic or other tools, resources, information and data used, or the analyses employed or relied on, by an investment manager, or if such tools, resources, information or data are used incorrectly, fail to produce the desired results, or otherwise do not work as intended. There can be no assurance that the use of these technologies will result in effective investment decisions for the Portfolio.

Focused Portfolio Risk: The Portfolio employs a strategy of investing in the securities of a limited number of companies. As a result, the Portfolio may incur more risk because changes in the value of a single security may have a more significant effect, either positive or negative, on the Portfolio’s net asset value. A portfolio using such a focused investment strategy may experience greater performance volatility than a portfolio that is more broadly invested.

Foreign Securities Risk: Investments in foreign securities, including depositary receipts, involve risks in addition to those associated with investments in U.S. securities. Foreign markets may be less liquid, more volatile and subject to less government supervision and regulation than U.S. markets, and it may take more time to clear and settle trades involving foreign securities, which could negatively impact the Portfolio’s investments and cause it to lose money. Security values also may be negatively affected by changes in the exchange rates between the U.S. dollar and foreign currencies. Differences between U.S. and foreign legal, political and economic systems, regulatory regimes and market practices, as well as trade barriers and other protectionist trade policies (including those of the U.S.), governmental instability, or other political or economic actions, also may adversely impact security values. World markets, or those in a particular region, may all react in similar fashion to important economic, political or other developments. Events and evolving conditions in certain economies or markets may alter the risks associated with investments tied to countries or regions that historically were perceived as

comparatively stable and make such investments riskier and more volatile. Regardless of where a company is organized or its stock is traded, its performance may be significantly affected by events in regions from which it derives its profits or in which it conducts significant operations.

New Portfolio Risk: The Portfolio is newly or recently established and has limited operating history. The Portfolio may not be successful in implementing its investment strategy, and there can be no assurance that the Portfolio will grow to or maintain an economically viable size, which could result in the Portfolio being liquidated at any time without shareholder approval and at a time that may not be favorable for all shareholders. Until the Portfolio is fully capitalized, it may be unable to pursue its investment objective or execute its principal investment strategies.

Sector Risk: From time to time, based on market or economic conditions, the Portfolio may have significant positions in one or more sectors of the market. To the extent the Portfolio invests more heavily in particular sectors, its performance will be especially sensitive to developments that significantly affect those sectors. Individual sectors may be more volatile, and may perform differently, than the broader market. The industries that constitute a sector may all react in the same way to economic, political or regulatory events.

Securities Lending Risk: The Portfolio may lend its portfolio securities to seek income. There is a risk that a borrower may default on its obligations to return loaned securities. The Portfolio will be responsible for the risks associated with the investment of cash collateral and may lose money on its investment of cash collateral or may fail to earn sufficient income on its investment to meet obligations to the borrower. Securities lending may introduce leverage into the Portfolio. In addition, delays may occur in the recovery of loaned securities from borrowers, which could interfere with the Portfolio’s ability to vote proxies or to settle transactions.

Risk Lose Money [Text]

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The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Portfolio.

Risk Not Insured Depository Institution [Text]

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An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Bar Chart and Performance Table [Heading]

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Risk/Return Bar Chart and Table

Performance Narrative [Text Block]

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The Portfolio is newly offered. Performance information will be available in the Prospectus after the Portfolio has been in operation for one full calendar year.

Performance One Year or Less [Text]

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Performance information will be available in the Prospectus after the Portfolio has been in operation for one full calendar year.

EQ/AB Sustainable U.S. Thematic Portfolio | Class IB Shares

Risk/Return:

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Shareholder Fees (fees paid directly from your investment)

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Management Fee

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0.65%

Distribution and/or Service Fees (12b-1 fees)

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0.25%

Other Expenses

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0.94%

^[1]

Total Annual Portfolio Operating Expenses

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1.84%

Fee Waiver and/or Expense Reimbursement

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(0.84%)

^[2]

Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement

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1.00%

1 year

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$ 102

3 years

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497

1 year

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102

3 years

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497

EQ/AB Sustainable U.S. Thematic Portfolio | Class K Shares

Risk/Return:

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Shareholder Fees (fees paid directly from your investment)

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Management Fee

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0.65%

Distribution and/or Service Fees (12b-1 fees)

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none

Other Expenses

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0.94%

^[1]

Total Annual Portfolio Operating Expenses

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1.59%

Fee Waiver and/or Expense Reimbursement

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(0.84%)

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Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement

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0.75%

1 year

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$ 77

3 years

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420

1 year

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3 years

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$ 420

[1]

Based on estimated amounts for the current fiscal year.

[2]

Pursuant to a contract, Equitable Investment Management Group, LLC (the “Adviser”) has agreed to make payments or waive its and its affiliates’ management, administrative and other fees to limit the expenses of the Portfolio through April 30, 2023 (unless the Board of Trustees consents to an earlier revision or termination of this arrangement) (“Expense Limitation Arrangement”) so that the annual operating expenses of the Portfolio (exclusive of taxes, interest, brokerage commissions, capitalized expenses, acquired fund fees and expenses, dividend and interest expenses on securities sold short, and extraordinary expenses not incurred in the ordinary course of the Portfolio’s business) do not exceed an annual rate of average daily net assets of 1.00% for Class IB shares and 0.75% for Class K shares of the Portfolio. The Expense Limitation Arrangement may be terminated by the Adviser at any time after April 30, 2023. The Adviser may be reimbursed the amount of any such payments or waivers in the future provided that the payments or waivers are reimbursed within three years of the payments or waivers being recorded and the Portfolio’s expense ratio, after the reimbursement is taken into account, does not exceed the Portfolio’s expense cap at the time of the waiver or the Portfolio’s expense cap at the time of the reimbursement, whichever is lower.