Most of what shapes your 2026 tax bill has to happen by December 31. Once the calendar turns, the year is locked in, and in April we can only report what happened.
The nine moves below are the ones we see matter most at year-end. Not all of them will apply to you. Skim the list, flag the ones that do, and call us before you act on the bigger ones.
The 9 moves
01Top off your 401(k)
By December 31Elective deferrals have to come out of a paycheck by December 31. Raising your percentage now only helps if there are pay periods left to run it through.
For 2026, the limit is $24,500 for 401(k), 403(b) and most 457 plans. If you're 50 or older, you can add an $8,000 catch-up, and if you're 60 to 63, a higher catch-up of $11,250 may apply. Starting in 2026, higher earners may have to make catch-up contributions as Roth contributions. Check with your plan administrator.
02Finish your charitable giving
By December 31A gift has to be completed by December 31 to count for 2026. Gifts of appreciated stock and contributions to a donor-advised fund can take several days to settle, so don't leave them for the last week.
New for 2026: if you take the standard deduction, you may still be able to deduct cash gifts to qualifying charities, up to $1,000 ($2,000 for married couples filing jointly). Gifts to donor-advised funds don't qualify for this deduction. If you itemize, new limits may reduce the benefit of some gifts. Ask us how they affect your plans.
03Review your gains and losses
By December 31Trades must execute by December 31 to count for 2026. Selling investments at a loss can offset gains you've already realized. Up to $3,000 of net losses ($1,500 if married filing separately) can also offset ordinary income, and any extra carries forward to future years.
Watch the wash-sale rule: if you buy the same or a substantially identical investment within 30 days before or after the sale, the loss is disallowed for now.
04Plan for the January 15 estimate
By January 15, 2027The fourth-quarter 2026 estimated payment is due January 15, 2027. To avoid an underpayment penalty, you generally need to have paid at least 90% of your 2026 tax, or 100% of your 2025 tax (110% if your 2025 adjusted gross income was over $150,000).
If you're short, there's a lever most people don't know about. Withholding is generally treated as paid evenly across the year, even if it comes out of a December paycheck. A W-4 change now can close a gap in a way a late estimate can't.
05Take your required minimum distribution
By December 31If you're 73 or older, your 2026 required minimum distribution (RMD) from IRAs and most retirement plans is generally due by December 31. Your first RMD can wait until April 1 of the following year, but then you'll take two in one year. A missed RMD can bring a penalty of up to 25%.
If you're charitable and 70½ or older, a qualified charitable distribution (QCD) sent directly from your IRA to a charity can count toward your RMD and stays out of your taxable income.
06Consider a Roth conversion
By December 31A Roth conversion has to be completed by December 31 to count for 2026. The amount you convert is taxed as ordinary income this year, and a conversion can't be undone.
It can make sense in a lower-income year, or when you expect to be in a higher bracket later. It works best when modeled against the rest of your return, so talk to us before you move money.
07Make your annual family gifts
By December 31For 2026, you can give up to $19,000 per recipient without filing a gift tax return, and married couples can give $38,000 together. The limit rises to $20,000 per recipient in 2027.
The gift has to be completed by December 31 to count for 2026. If you give by check, send it early enough for the recipient to deposit it before year-end.
08Use up your FSA balance
Check your plan's deadlineHealth flexible spending account (FSA) money is generally use-it-or-lose-it. Some plans let you carry over a limited amount (up to $680 into 2027) or offer a grace period of up to two and a half months, but not both. Check your plan's rules and schedule any appointments or purchases now.
09Business owners: time your equipment purchases
Placed in service by December 31For a year-end equipment or vehicle purchase, the test is whether the asset is placed in service by December 31. Ordering or paying for it isn't enough.
For 2026, Section 179 lets businesses expense up to $2,560,000 of qualifying property. The deduction can't create or increase a loss, so it may be limited by the income your business actually reports. Under the 2025 tax law, 100% bonus depreciation is also available for qualifying property acquired after January 19, 2025. Model the purchase with us before you sign, not after.
One rule covers all nine
Call us before the big moves, not after. Most of these decisions interact: a Roth conversion changes your bracket, a large gift changes what you can deduct, and an equipment purchase depends on what the business earned. A quick conversation in December can save a surprise in April.
Talk to Our Team →This article is for general information only and isn't tax advice for your situation. Tax rules and limits change, so talk with us before acting on any of these items.