Vanguard research
April 08, 2026
Private equity is an important and growing component of the investing landscape, offering eligible investors the potential for enhanced returns along with modest diversification benefits. However, these benefits come with significant active risk and limited liquidity. A new Vanguard research paper notes that some investors overlook key attributes of private equity in their decision-making, potentially resulting in suboptimal allocations. The paper examines how these realities can materially affect return expectations and provides a framework to help investors and advisors decide whether and how much private equity belongs in a portfolio.
Private equity has evolved this century from a niche institutional asset to a more mainstream option, now representing 8% of the global investable equity market, up from 1% in 2000. The number of U.S. companies backed by private equity has multiplied and private equity fund formation has surged, reflecting both industry maturation and growing investor demand.
Driving the upswing in private equity’s popularity is its potential to enhance long-term portfolio returns. That potential stems from its opportunity to capture liquidity risk premia and manager alpha while also broadening equity market exposure.
A number of structural challenges mean that adding private equity to a portfolio in pursuit of higher overall returns merits careful consideration. These challenges include:
As an example of these challenges: Private equity can provide a modest diversification benefit by broadening a portfolio’s equity market coverage, but appraisal-based pricing can overstate this benefit if values appear artificially stable. When adjusting for appraisal bias, private equity’s historical performance drops in line with that of public equity during market downturns like the tech bubble in the early 2000s, the 2008 global financial crisis, and the onset of the COVID-19 pandemic in 2020. Thus, while private equity can broaden market coverage, it shouldn’t be relied upon as a risk-off hedge.
Vanguard’s approach emphasizes structured analysis, factoring in return drivers, liquidity constraints, cash-flow uncertainty, manager dispersion, and an investor’s tolerance for systematic, liquidity, and active risk.
When realistically modeling volatility, active risk, and liquidity constraints, the appropriate allocation to private equity can vary widely—from 0% to 40% of a portfolio’s total equity—depending on an investor’s ability to:
As a result, private equity can be a meaningful allocation, but it is not always a suitable option, even for otherwise qualified investors.
Private equity offers significant potential but requires strong due diligence, realistic expectations, and appropriate risk tolerance from investors. When evaluated through a disciplined, evidence-based framework, private equity’s potential benefits can be weighed against meaningful liquidity and active risks. A right-sized approach—grounded in rigorous manager selection, liquidity awareness, and thoughtful portfolio integration—can enhance outcomes for suitable investors, ensuring a proper fit.
Notes:
Private investments involve a high degree of risk and, therefore, should be undertaken only by prospective investors capable of evaluating and bearing the risks such an investment represents. Investors in private equity generally must meet certain minimum financial qualifications that may make it unsuitable for specific market participants.
All investing is subject to risk, including the possible loss of the money you invest. Be aware that fluctuations in the financial markets and other factors may cause declines in the value of your account. There is no guarantee that any particular asset allocation or mix of funds will meet your investment objectives or provide you with a given level of income.
Diversification does not ensure a profit or protect against a loss.
This material is provided for informational purposes only and is not intended to be investment advice or a recommendation to take any particular investment action.
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