Ways to Save on Taxes After December 31 (But Before You File)

So the calendar flipped to January, and you’re thinking, “Welp, my tax-saving window is closed.”

Not quite!

While many tax strategies do have a hard cutoff at December 31, there are still a few powerful moves you can make between January 1 and the day you file your tax return — and they can make a meaningful difference.

Here’s how:

1. Contribute to an IRA (Traditional or Roth)

You can make contributions to your IRA for the previous tax year all the way up to the tax filing deadline (typically around April 15). That means if you didn’t max out your IRA by December 31, you still have time to add funds and and potentially reduce your taxable income.

• Traditional IRA: Contributions may be tax-deductible, depending on your income and whether you or your spouse are covered by a retirement plan at work. Please work with a CPA before you make a contribution.

• Roth IRA: Contributions aren’t deductible, but you get tax-free growth and withdrawals in retirement. However, your income may be too high for a Roth IRA contribution. Please work with a CPA before you make a contribution.

I’m hoping the third time is a charm when I say this: PLEASE work with a CPA before you make a contribution to your IRA or Roth IRA. If you make non-deductible IRA contributions with the idea of doing a Backdoor Roth conversion, you can trigger major unintended tax consequences if you have any pre-tax IRA accounts. If your income surpasses the IRA mandated limits for Roth IRA contributions, you might face penalties for making excess contributions if not rectified in a timely manner.

2. Fund a Health Savings Account (HSA)

If you were covered by a high-deductible health plan (HDHP), you can still make a prior-year HSA contribution up until the filing deadline.

• Contributions are tax-deductible, earnings grow tax-free, and withdrawals are tax-free for qualified medical expenses.

• Triple tax benefit? Yes, please.

For 2024 tax year contributions:

• $4,150 for individuals

• $8,300 for families

• Add $1,000 if you’re 55+

For 2025 tax year contributions:

• $4,300 for individuals

• $8,5500 for families

• Add $1,000 if you’re 55+

An HSA is one of the most tax-advantaged tools out there — if you can afford to let the money grow for future health costs. If you’re making the contribution just to spend it within a year or so, the tax benefits are limited to the initial tax deduction. (Still a good thing!)

3. Make a SEP IRA Contribution (If You’re Self-Employed)

For business owners or freelancers, a SEP IRA is a powerful way to save on taxes. You can contribute for the previous year all the way up to your tax-filing deadline — and if you file an extension, you get even more time (until October 15).

Plus, the SEP IRA contribution is not subject to one-half (the employer portion) of the FICA taxes due on your Schedule C net profit.

Contribution limits are high (up to 25% of compensation or $69,000 for 2024 // $70,000 for 2025), and contributions are deductible. This is one of the few ways to make a sizable tax-deductible move after year-end.

Review Your Withholding and Estimated Taxes

While this won’t reduce your last year’s taxes, it’s a great time to adjust your withholding or quarterly estimated payments so you’re not caught off guard next year. A little planning now can help you avoid penalties — or a negative surprise — later.

Have questions about which ones make sense for your situation? Let’s talk about it before your taxes are due.