Here’s the tax planning checklist for 2026 in one breath: max out retirement contributions, fill your HSA, harvest investment losses, prepay or postpone deductible expenses, make charitable gifts and annual-exclusion gifts before December 31, and check your withholding before the year closes. Most of these moves are gone once the calendar flips, which is exactly why the last two months of the year are the most valuable tax-planning window you get. Below are twelve moves, with the 2026 numbers that make them concrete.
1. Max out your 401(k), 403(b), or 457 before the last payroll
The employee deferral limit rises to $24,500 for 2026, up from $23,500, according to the IRS’s annual announcement (IR-2025-111). If you’re 50 or older, you can add an $8,000 catch-up. If you turn 60 to 63 in 2026, the higher SECURE 2.0 catch-up stays at $11,250. Payroll contributions generally must happen before your final paycheck of the year, so adjust the deferral percentage in the next pay cycle, not in December’s panic.
2. Fund an IRA (you have until April, but why wait)
The IRA contribution limit for 2026 is $7,500, with a $1,100 catch-up for those 50 and older (same IRS announcement). Traditional IRA contributions may be deductible depending on income and workplace plan coverage; Roth contributions follow income phase-outs. The deadline for 2026 contributions is the April 2027 filing deadline, but funding now gives your money more time in the market and gives you one less thing to forget.
3. Fill the HSA while you still can
For 2026, health savings account contributions are capped at $4,400 for self-only coverage and $8,750 for family coverage, plus a $1,000 catch-up at age 55 (IRS Rev. Proc. 2025-19). HSAs are the rare triple-tax-advantaged account: deductible going in, tax-free growth, tax-free coming out for qualified medical expenses. If your employer contributes, subtract that from your own target so you don’t overshoot the combined limit.
4. Harvest investment losses (and check gains)
If you sold winners this year, look for losing positions to sell before December 31. Losses offset gains, and up to $3,000 of net losses can offset ordinary income per year, with the excess carried forward. Mind the wash-sale rule: don’t repurchase a substantially identical security within 30 days before or after the sale.
5. Make charitable gifts by December 31
Cash and appreciated-stock gifts count only if completed by year end. Donating appreciated securities directly is usually smarter than selling and gifting cash, since you skip the capital gain. Keep records: the IRS requires written acknowledgment from the charity for gifts of $250 or more. If you take the standard deduction, bunching several years of giving into one year can still matter through donor-advised funds.
6. Use your annual gift tax exclusion
You can give up to $19,000 per recipient in 2026 without touching your lifetime exemption or filing a gift tax return (IRS Rev. Proc. 2025-32). Married couples can give $38,000 each. This is one of the cleanest estate-planning moves available every year, and it expires with the calendar. We cover how this fits into passing wealth on in protecting and passing on what you build.
7. Take required minimum distributions
If you’re of RMD age, the penalty for missing one is steep, and 2026 is not the year to discover that rule. The exact age depends on your birth year under the SECURE 2.0 schedule. QCDs (qualified charitable distributions) from IRAs can satisfy RMDs and keep the income off your return entirely if you’re charitably inclined.
8. Do a Roth conversion math check
Converting traditional IRA money to Roth before December 31 makes sense when this year’s income is unusually low or when you expect higher rates later. Fill up the current bracket rather than crossing into the next one. Conversions can’t be undone, so run the numbers against next year’s expected income before committing.
9. Spend down use-it-or-lose-it accounts
Flexible spending accounts often forfeit unspent balances at year end, though some plans offer a grace period or a small carryover. Check your plan’s rules now. If you have money left, schedule the dental work or new glasses before the deadline.
10. Prepay or postpone deductible expenses
If you itemize, timing deductions around the year boundary is legitimate tax planning. Property taxes, mortgage interest, and charitable gifts all fall into whichever year you pay them. The same logic runs in reverse: if next year’s income will be higher, pushing deductible payments into January can save more.
11. Adjust withholding or estimated payments
A surprise tax bill in April often has a boring cause: withholding that drifted out of date after a raise, a side hustle, or a spouse’s job change. Use the IRS withholding estimator and adjust your W-4 now, or make a fourth-quarter estimated payment (due January 15) to avoid underpayment penalties.
12. Check your contribution limits and income phase-outs one last time
The 2026 numbers in one place:
| Item | 2026 limit | Source |
|---|---|---|
| 401(k)/403(b)/457 deferral | $24,500 | IRS Notice 2025-67 |
| Catch-up, age 50+ | $8,000 (workplace plans), $1,100 (IRA) | IRS Notice 2025-67 |
| Catch-up, ages 60 to 63 | $11,250 | IRS Notice 2025-67 |
| IRA contribution | $7,500 | IRS Notice 2025-67 |
| HSA (self-only / family) | $4,400 / $8,750 | IRS Rev. Proc. 2025-19 |
| Annual gift exclusion | $19,000 per recipient | IRS Rev. Proc. 2025-32 |
| Standard deduction (single / joint) | $16,100 / $31,500 | IRS Rev. Proc. 2025-32 |
Frequently asked questions
What is the deadline for year-end tax planning?
Most moves must be completed by December 31: retirement deferrals, charitable gifts, Roth conversions, loss harvesting, and annual gifts. IRA and HSA contributions for 2026 can technically be made until the April 2027 filing deadline, but payroll-based moves are gone after your last paycheck.
Does it make sense to overfund my 401(k) at the end of the year?
Watch for one trap: if you hit the deferral limit early, some employers stop matching contributions for the rest of the year. Spread contributions so you receive the full match every pay period rather than front-loading and finishing in September.
Can I still do tax-loss harvesting in December?
Yes, and most people do it in December because that’s when the year’s gains are visible. Just place the trades with enough time to settle before year end, and observe the wash-sale rule if you want to keep similar exposure.
What if I take the standard deduction? Is tax planning still worth it?
Absolutely. Retirement contributions, HSA funding, loss harvesting, and Roth conversions all work regardless of how you deduct. The 2026 standard deduction is $16,100 for single filers and $31,500 for joint filers, and most taxpayers take it.
How do I know which of these moves apply to me?
Start with the four universal ones: workplace retirement plan, IRA, HSA (if eligible), and withholding check. Then layer on the situational moves. If your taxes involve equity compensation, a business, or rental property, a professional review will usually pay for itself.
Conclusion
Tax planning is a deadline sport, and December 31 is the finish line for most of it. Work the checklist top to bottom this week: contribution limits first (they’re mechanical), then timing moves like loss harvesting and charitable gifts (they need a calendar), then the checkups. If deductions are the part of the puzzle you’re shaky on, our guide to legal tax deductions for beginners fills in the gaps, and these wealth management tips show how the tax work fits the bigger picture.