For advisors managing high-net-worth households, the choice of “wrapper”—exchange-traded funds or mutual funds choice—is no longer just a matter of preference; it is a critical lever for maximizing aftertax alpha.
The data from recent market cycles serves as a stark warning. In up years, like 2025, strong market returns forced many mutual fund managers to realize gains to rebalance, resulting in widespread payouts. In 2025, roughly 72% of the US equity mutual funds issued capital gains distributions, with average payouts ranging from 7% to 10% of the net asset value.
However, the “phantom” tax liability is even more damaging during down cycles. In 2022, the S&P 500 declined by over 18%, yet two-thirds of all US equity mutual funds still distributed capital gains, averaging 7% of NAV. This tax sting in a down year highlights a fundamental flaw in the mutual fund structure: Investors are often forced to pay taxes on a losing investment.
Here are the six reasons why the ETF wrapper is the superior fiduciary choice for taxable portfolios in 2026:
1. Structural Mitigation of Phantom Tax Liability
Mutual funds suffer from an inherent “collective action” flaw: The behavior of your fellow investors dictates your tax bill. In both up and down markets, this creates a tax drag that erodes compounding. ETFs use the in-kind creation and redemption process. By exchanging baskets of underlying securities with market makers rather than selling for cash, the ETF manager can purge low-basis shares without a taxable event. Says Phil McInnis, chief investment strategist at Avantis Investors, “ETFs are far less likely to distribute capital gains, so it puts the control back in the advisor and client’s hands from a tax planning perspective.”
2. Lessons From the Double-Whammy Years
History shows that mutual fund distributions are often highest when investors can least afford them. For a client with a $1 million taxable portfolio, a 7% distribution in a down year (like 2022) results in a $70,000 taxable event. At a 23.8% tax rate (including the net investment income tax), that is a $16,660 tax bill on a losing investment. ETFs effectively eliminate this insult-to-injury scenario.
3. Enhanced Operational Transparency
In today’s sophisticated landscape, the traditional mutual fund’s “black-box” quarterly reporting is insufficient. Most ETFs provide daily transparency of holdings. This allows for precise risk monitoring, ensuring that a portfolio isn’t overconcentrating in high-risk sectors or closet indexing against a benchmark the client already owns.
4. Intraday Agility and Liquidity Control
While critics point to intraday volatility as a negative, it is actually a risk-management feature. Mutual funds offer a single liquidity point at 4 p.m. Eastern time. To mitigate the risk of wide bid-ask spreads, advisors should avoid the volatility zones (the first and last 30 minutes of the trading day) and use limit orders.
5. Precision in Tax-Loss Harvesting
Harvesting losses in a mutual fund can be clunky, often requiring a 30-day wait in cash or temporarily investing in a suboptimal fund to avoid wash-sale rules. The vast universe of specialized ETFs allows advisors to swap between highly correlated but distinct wrappers to maintain market exposure while locking in the tax benefit immediately.
6. Solving for the Cash Drag Problem
Mutual funds typically maintain a cash cushion (often 3% to 5%) to handle daily redemptions. Because ETFs trade on the secondary market between investors, the fund manager can remain nearly 100% invested. Over a long-term horizon, reclaiming that 3% cash drag can translate to significantly higher compounded growth.
The Conclusion: A Structural Fiduciary Duty
While mutual funds still offer utility for automated 401(k) contributions, for the taxable brokerage account, the evidence is overwhelming. In 2026, the ETF isn’t just a trading vehicle; it is a tax-management technology. “The shift from mutual funds to ETFs among advisors has been substantial,” McInnis says. “The ETF is a more modern vehicle, and the potential efficiencies can translate to real differences over time.”
By selecting the ETF wrapper, advisors are fulfilling their duty to maximize client wealth by minimizing the friction of unnecessary distributions and internal costs.