Investment in American financial markets stands as a cornerstone of the nation’s long-term economic trajectory. How the federal tax code treats these investments directly impacts after-tax returns to saving, shaping the choices Americans make when allocating their capital. For years, however, structural differences in how various investment vehicles operate have created unintended tax disadvantages for ordinary savers, occasionally acting as a barrier to domestic investment.
To address these disparities, federal lawmakers have introduced bipartisan-backed legislation aimed at modernizing investment taxation. The Generating Retirement Ownership Through Long-Term Holding (GROWTH) Act, proposed in both chambers of Congress this session by Senator John Cornyn (R-TX) and Representative Beth Van Duyne (R-TX), seeks to make the tax treatment of investment funds more consistent. By allowing investors to defer taxes on qualifying reinvested capital gains distributions until they actually sell their fund shares, the legislation aims to improve the overall tax environment for saving in the United States.
At the heart of the debate are two of the most popular vehicles for everyday investors: mutual funds and exchange-traded funds (ETFs). While both investment types are subject to the same fundamental tax rules as regulated investment companies (RICs), they operate and process redemptions in fundamentally different ways. These operational differences can produce drastically divergent tax outcomes for shareholders who hold virtually identical portfolio assets.
To understand the disparity, consider a conventional mutual fund that owns a stock with an underlying cost basis of $20 and a market value of $100. When a shareholder decides to redeem $100 worth of mutual fund shares, the fund may be forced to sell $100 of its underlying stock to cover the payout, thereby realizing an $80 capital gain. Under current law, this net capital gain is distributed directly to the fund’s shareholders. Crucially, it is taxed at the shareholder level rather than within the fund itself. This means that remaining shareholders often find themselves owing capital gains tax on transactions they did not initiate, even though they never sold any of their own fund shares.
Contrast this dynamic with an exchange-traded fund. Retail ETF shareholders typically sell their shares to other investors on secondary markets rather than redeeming them directly from the fund itself. Furthermore, authorized participants can exchange blocks of ETF shares when redeeming them from the fund for a basket of underlying securities. These in-kind redemptions bypass the need to sell underlying assets for cash, avoiding the realization of capital gains that would otherwise be distributed to remaining shareholders.
Consequently, an investor can own virtually the exact same portfolio holdings and earn the identical investment return, yet face starkly different current tax liabilities depending entirely on whether their money is pooled in a mutual fund or an ETF.
While investors in both types of funds must eventually pay capital gains tax upon the ultimate sale of their shares, mutual fund investors routinely face capital gains tax liabilities even while holding their positions. This structural quirk leads to divergent after-tax returns depending on the underlying fund type. The real-world consequences are measurable; historical data indicates that average capital gains distributions are markedly higher for mutual funds than they are for ETFs.
The GROWTH Act would address this imbalance by deferring the recognition of qualifying reinvested capital gains until investors finally sell their fund shares. This change would effectively narrow the gap in the timing of capital gains taxation between mutual fund and ETF shareholders in practice. Meanwhile, dividend and interest income generated by these funds would continue to be taxed exactly as they are under current law.
From a tax policy and neutrality perspective, the underlying argument for the legislation is straightforward. Economists and policy analysts argue that the tax code should be designed so that investors make decisions regarding underlying investments and fund vehicles based entirely on economic merits rather than maneuvering around tax consequences.
Economic modeling of the proposal provides a clear picture of its budgetary impact. Analysts estimate that the GROWTH Act proposal would reduce federal revenue by $37.7 billion from 2027 to 2036 on a conventional basis. Similar to other proposed timing changes within the tax code, this fiscal cost is front-loaded. Reinvested amounts that were previously subject to immediate capital gains taxation would suddenly qualify for deferral, while few of those newly deferred amounts would be sold right away.
Over time, however, this net cost drops as deferred amounts are eventually sold and taxed. This dynamic leads to a lower, steady-state cost just above $1 billion per year in the latter part of the standard budget window. While the proposal would incur a net long-run cost to the federal government, the annual revenue loss falls substantially as prior deferred gains are eventually recognized and processed by the system.
In the long run, the conventional revenue cost may ultimately be somewhat smaller than the formal scored estimate. This is because reinvested returns that make up the deferred tax liability can themselves compound over time and become subject to taxation later—an interactive effect that is frequently excluded from baseline conventional revenue estimates.
From a distributional standpoint, the legislation would provide modest, broad-based relief. The GROWTH Act is projected to increase after-tax incomes by an average of 0.1 percent across the board in 2027. By 2036, the change in annual tax liabilities diminishes, leading to an increase of less than 0.05 percent in after-tax incomes across the income spectrum.
By increasing the net after-tax returns to saving, the GROWTH Act would also serve to boost the long-run gross national product, capturing a rise in the overall income earned by American residents. However, the ultimate net economic impact of the proposal would depend heavily on how any resulting federal revenue loss is financed. For example, if the lost revenue were to be offset through additional federal borrowing, higher national debt would inevitably increase interest payments flowing to foreign investors, thereby offsetting a portion of the domestic increase in American incomes.
Advocates emphasize that the GROWTH Act would successfully improve horizontal equity and neutrality within the tax code by ensuring that identically situated investors across both mutual funds and ETFs face comparable tax liabilities. Yet, as with nearly all tax policy proposals, notable trade-offs exist.
By expanding the scope of tax deferral within the individual income tax system, the proposal would inherently encourage taxpayers to slow down their pace of capital gains realizations for tax planning purposes. This classic economic "lock-in" effect can sometimes prevent capital from being freely reallocated to more productive, dynamic uses within the broader economy. Nevertheless, the proposal’s built-in rules preventing taxpayers from avoiding tax altogether via traditional mechanisms help limit this distortionary incentive.
On balance, policy experts view the GROWTH Act as a targeted and meaningful improvement in tax neutrality, even if broader, more sweeping reforms to the tax treatment of saving and investment would be required to eliminate systemic distortions in capital gains taxation entirely. Ideally, many economists argue, the tax code should play a minimal role in determining how ordinary taxpayers invest their hard-earned money and which fund structures they ultimately choose.
