- Required minimum distributions generally have to be taken before Dec. 31
- Workers have until the end of the year to contribute to their 401(k)s
- FSA funds typically have to be used before the end of the year
Contribute to tax-advantaged accounts
Most workers have until Dec. 31 to make contributions to employer retirement plans like 401(k)s and 403(b)s. Adding money before the deadline can lower your taxable income for the year and help you get the most out of any employer match.
For 2025, individuals can contribute up to $23,500 to a 401(k). Those who are age 50 or older can put in an additional $7,500 in catch-up contributions.
Savers have longer when it comes to IRAs and Health Savings Accounts (HSAs) — contributions to both are allowed until next April’s tax deadline. Still, putting money in sooner can add up over time, since it gives your investments more time to grow.
Turn investment losses into tax wins
If you have investments that lost value this year, selling them before Dec. 31 can help lower your tax bill. It’s a strategy known as tax-loss harvesting — using losses to offset any capital gains you realized.
If your losses exceed your gains, you can deduct up to $3,000 against ordinary income, with any leftover losses carried forward to future years.
To make the most of the strategy, many advisors recommend reinvesting the proceeds into a different security that fills a similar role in your portfolio — keeping your money working in the market. Vanguard says that step is what separates smart tax planning from simply trying to time the market.
Just be sure to avoid a “wash sale“: You won’t get the tax benefit if you turn around and buy the same or a “substantially identical” security within 30 days before or after the sale.
Make charitable contributions
Donating to charity can lower your taxable income, but timing matters — contributions must be made by Dec. 31 to count for this year’s return.
To be eligible for a deduction, the donation has to be made to a qualifying organization, which the IRS lists here. There’s also a search tool to verify specific groups’ tax-exempt status.
From a tax savings standpoint, charitable deductions only matter if you itemize. They won’t reduce your tax bill if you take the standard deduction.
Don’t forget to use your FSA funds
Flexible Spending Accounts, FSAs, are tax-favored accounts that can be used to pay for eligible health care expenses, but the money generally has to be used by the end of the year.
According to FSA Store, an online retailer for FSA-eligible products, nearly 70% of FSA users face a Dec. 31 deadline, and billions of dollars in unspent funds go unused each year.
Some employers may offer a short grace period or allow a small amount to carry over, but for most people, FSA money is essentially “use it or lose it.”
That’s a key difference from HSAs, where unused funds roll over year to year and don’t expire.
FSA dollars can be used for a wide range of eligible costs, including deductibles, copayments, prescription medications and certain medical supplies.


