Investors who sold stocks, funds, or property this year could owe the IRS a bigger slice than they expect.
The long-term capital gains tax brackets are adjusting for 2026, and the thresholds are moving in a way that catches some middle-income savers off guard.
For 2025, single filers pay 0% on long-term gains up to $48,350.
That figure is projected to rise to roughly $49,450 in 2026, according to inflation-adjusted estimates from the IRS and tax analysts.
Married couples filing jointly would see their 0% ceiling climb from $96,700 to about $98,900.
The catch is that these brackets apply only to assets held longer than a year.
Sell a stock you bought 11 months ago and the profit gets taxed as ordinary income — your marginal rate, which can run 22% or higher.
That single detail costs American households billions in avoidable taxes every year.
Here's where it gets tricky for retirees and part-time traders.
Capital gains stack on top of ordinary income.
A couple earning $80,000 from pensions and Social Security who also books $30,000 in long-term gains doesn't get the full 0% treatment — part of that gain lands in the 15% bracket.
Many filers don't realize this until their tax preparer breaks the news.
The 15% bracket stretches to $533,400 for singles and $600,050 for joint filers in 2025, with modest increases expected next year.
Above those levels, the top rate hits 20%.
Add the 3.8% net investment income tax for high earners, and the effective rate can approach 24%.
A few moves can soften the blow without triggering IRS red flags.
Tax-loss harvesting — selling losers to offset winners — remains one of the simplest tools.
So does timing: if you're near a bracket edge, spreading a sale across two calendar years can keep more of the gain in the 0% or 15% zone.
Municipal bonds and qualified opportunity zone funds draw attention from wealthier investors, though both carry real risk and liquidity tradeoffs.
For most households, maxing out a Roth IRA or 401(k) and holding investments longer than 12 months does more good than any exotic strategy.
One quiet trap: mutual fund capital gains distributions.
Even if you didn't sell a single share, a fund manager's trades inside the fund can hand you a taxable distribution in December.
Check your fund's estimated distribution before year-end, especially in actively managed accounts.
Another wrinkle for 2026 — the enhanced standard deduction and other provisions from recent tax legislation could shift how much ordinary income you report, which in turn changes how much room you have in the 0% capital gains bracket.
Nothing is final until the IRS publishes official figures, usually in the fall.
The takeaway for everyday investors is straightforward.
Know your bracket, watch the calendar, and don't let a fund manager's December surprise wreck your tax bill.
Final Thoughts
A 20-minute call with a tax pro before you sell can save more than most people earn in a week.