5 Upcoming Deadlines All Retirees Need to Mark on Their Calendars

The end of the year is often hectic as we juggle vacation schedules, holiday gatherings, and new financial strains. The beginning of a new year isn't always a lot better. You're trying to recover from the holidays and maybe work toward a New Year's resolution.

Amid all that, it's easy to let other things, like retirement healthcare and financial moves, fall through the cracks. A simple way to prevent this is to write down important deadlines in a place where you won't forget them. Here are five worth remembering over the next few months.

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1. Dec. 7, 2025

Dec. 7, 2025 marks the end of Medicare's 2025 open enrollment period. This is usually the only time you have to make changes to your health insurance policy for 2026. There are exceptions if you qualify for a special enrollment period, like quitting your job or moving to another state, but if this doesn't apply to you, now is the time to start comparing coverage options for next year.

Focus on both coverage and cost. If you want to change plans, act within the next couple of weeks. If you don't make changes, you'll continue with your existing plan in 2026.

2. Dec. 31, 2025

The end of the year also marks the final day you're able to make 2025 401(k) contributions. This may not apply to you if you're fully retired. But if you are still working and you're looking to lower your tax liability for the year, a 401(k) contribution could be a good way to do it. Just ensure that you stay under the contribution limits to avoid penalties.

Dec. 31, 2025 is also the deadline for most seniors over 73 to take their required minimum distributions (RMDs). These are mandatory annual withdrawals from all your tax-deferred retirement accounts. You're only allowed to skip an RMD from your current 401(k) if you're still working and own less than 5% of the company.

3. March 31, 2026

If you're currently on a Medicare Advantage plan, your open enrollment period runs from Jan. 1, 2026 to March 31, 2026. You're free to compare plans and elect new coverage during that time. If you do this, your new coverage will begin on the first day of the following month. For example, if you make the change on Feb. 15, 2026, your new coverage will begin March 1, 2026.

Again, you may be eligible to switch plans outside of this window if you qualify for a special enrollment period. However, it's still worth reviewing your options during the open enrollment period while you have the chance.

4. April 1, 2026

If you just turned 73 in 2025, you have until April 1, 2026 to take your first RMDs. However, you don't have to wait this long. You're free to take yours in the next few weeks if you prefer.

It's important not to miss this deadline, or you could pay a 25% penalty on the untaken RMD. This will likely result in higher taxes than what you'd pay if you took your RMD as scheduled.

5. April 15, 2026

In addition to being tax day, April 15, 2026 also marks the final day you can make 2025 IRA and health savings account (HSA) contributions. This could reduce your taxable income for 2025 while also helping you prepare for your future.

If you decide to make a 2025 IRA or HSA contribution in 2026, contact your plan provider first to ensure it applies your contribution to the correct year. Otherwise, it might default to 2026.

These moves may not all apply to you, but make a note of the ones that do and set reminders for yourself so you don't miss them. You could make a note on your calendar or set a reminder on your phone. Just make sure it's something you won't overlook.

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