Year-end money moves: what to do before December 31, 2026

Short answer

Five things have a hard deadline of December 31, 2026: 401(k) contributions, spending your FSA, selling investments at a loss to offset gains, taking required minimum distributions, and charitable gifts. IRA and HSA contributions for 2026 can wait until the April 2027 filing deadline. Start with the 401(k) — payroll needs time to change your rate before the last checks of the year.

Deadline December 31

1. Top up your 401(k)

The 2026 employee limit is $24,500, plus a catch-up of $8,000 at age 50+ — or $11,250 if you're 60 to 63. Contributions only come from paychecks, so raise your percentage now for the remaining checks. In a traditional 401(k), every dollar lowers this year's taxable income: an extra $3,000 saves about $660 of federal tax in the 22% bracket ($360 in the 12% bracket). Not sure whether traditional or Roth is better for you? Compare them with the Roth vs traditional calculator, and see what maxing out grows to with the 401(k) calculator.

2. Use your health FSA

Health FSA money is mostly use-it-or-lose-it. Plans can let you carry up to $680 into next year or give you a grace period — check yours. Eyeglasses, contacts, dental work and many pharmacy items qualify. For 2027 enrollment, the 2026 limit was $3,400; your employer will show the new figure.

3. Harvest investment losses (taxable accounts only)

Selling an investment that's down lets the loss offset gains you've taken this year, and up to $3,000 of extra loss can reduce your other income ($1,500 if married filing separately). Unused losses carry forward. Don't buy the same or a substantially identical fund within 30 days before or after the sale, or the wash-sale rule disallows the loss for now.

The flip side: if your taxable income is low, you may pay 0% tax on long-term gains — up to $49,450 of taxable income for single filers and $98,900 for married couples filing jointly in 2026. Selling winners up to that line ("gain harvesting") resets your cost basis for free. Check your bracket with the income tax calculator.

4. Take your required minimum distribution

If you're 73 or older, take this year's RMD from traditional IRAs and 401(k)s by December 31 (your very first one can wait until April 1 of the next year — but then you'd take two in one year). Missing it costs a 25% excise tax on the shortfall, 10% if corrected within two years. Roth IRAs have no RMDs for the original owner.

5. Give to charity — new rules for 2026

Starting this year, people who take the standard deduction can still deduct up to $1,000 of cash donations ($2,000 married filing jointly). Gifts must reach the charity by December 31 (a card charge or a check mailed by then counts). Property gifts and donor-advised funds don't qualify for this one. Keep the receipt.

Deadline April 2027

6. IRA contributions

You can put up to $7,500 ($8,600 at 50+) into an IRA for 2026 until the filing deadline. A Roth IRA phases out between $153,000 and $168,000 of income for single filers ($242,000–$252,000 married filing jointly). See what it adds up to with the Roth IRA calculator.

7. HSA contributions

With a high-deductible health plan you can add up to $4,400 (self-only) or $8,750 (family) for 2026, plus $1,000 at 55+, until the filing deadline. HSA money is deductible going in, grows tax-free and comes out tax-free for medical costs — the HSA calculator shows the tax you save.

Two more checks before the year ends

• 8. Your withholding. A big raise, a side gig or a second job can leave you short. Run your numbers in the paycheck calculator and adjust your W-4 for the last checks — or make a fourth-quarter estimated payment by mid-January if you're self-employed (self-employment tax calculator).
• 9. Open enrollment. Employer benefits and the ACA marketplace both set next year's health coverage now. Marketplace enrollment for 2027 runs November 1 to January 15 — enroll by December 15 for January 1 coverage. Estimate your price with the ACA subsidy calculator.

What changes for 2027

The IRS publishes next year's tax brackets and retirement limits in the fall. We update our calculators the week they're released — Social Security's 2027 numbers are already in: a 3.6% COLA and a $192,300 wage base (details).