Year-End Retirement Account Strategies (And the New Rules Coming in 2026)

Year-End Retirement Account Strategies (And the New Rules Coming in 2026)

When it comes to retirement accounts timing is just as important as strategy. Some moves are truly “use it or lose it” by December 31. Others can wait until tax filing time. And starting in 2026, several new rules will change how much you can save, and whether certain contributions must be Roth.

This article breaks it all down so you know:

• What has to be done by December 31, 2025
• What can wait until the 2026 tax deadline (for 2025 contributions)
• What’s changing for IRAs and 401(k)s in 2026

1. Year-End Moves for Your 401(k) at Work

If you have a 401(k) with an employer, December 31, 2025 is the key cutoff for 2025 contributions.

Get the full match

If your employer offers a match – say, 100% up to 4% of your compensation—year-end is your last chance to make sure you’ve contributed enough to get the entire match.

Example:

• You earn $100,000
• The plan matches dollar-for-dollar up to 4%
• If you contribute $4,000, the employer adds $4,000

That extra $4,000 is essentially a 100% return on your contribution. If you’ve only put in 2% so far, you’ve only unlocked half the match. Before December 31, increase your deferral rate (or do a lump sum) so that you hit the full match under your employer’s plan. It’s free money, go claim it.

Aim higher if you can:

For 2025:

• Employee 401(k) deferral limit: $23,500
• Age 50+ catch-up: $7,500

You don’t have to spread contributions evenly through the year. If you have the cash flow, you can increase your deferral in the final pay periods to get closer to the annual limit. Just remember: in an employer 401(k) once the calendar flips to 2026, you’re contributing toward the new year, not 2025.

Mega backdoor Roth (for advanced savers)

If your employer’s plan allows after-tax contributions and in-plan Roth conversions or in-service rollovers, you may be able to use the mega backdoor Roth to push total 401(k) contributions to $70,000 for 2025.

Because these contributions run through the employer plan, this is also a plan-year / December 31 strategy. If you want to use it for 2025, it has to be set up and executed before year-end.

Bonus: Paying Kids for Their Roth IRA

If your child has earned income in 2025 (e.g. wages from a summer job or legitimate work in your business), they can contribute to a Roth IRA up to the lesser of their earned income or the annual limit. A common strategy is for the parent to “match” or gift the contribution amount while the child keeps their earnings.

The key year-end task is to make sure the income is real and documented (W-2 or 1099, or clean books if they work in your business) so you can confidently fund a 2025 Roth IRA for them before the April 15, 2026 deadline.

2. Roth Conversions: Choosing the Right Year

Converting pre-tax dollars (Traditional IRA or 401(k)) to Roth is a powerful way to get more money into accounts that grow and come out tax-free in retirement.

The timing matters because:

• A conversion in 2025 is reported on a 2025 Form 1099-R and taxed on your 2025 return
• A conversion in 2026 shows up on your 2026 return

That gives you two levers to pull:

Use low-income years and market dips

If your income in 2025 is unusually low—or if your portfolio is temporarily down—you may want to convert before year-end so you:

• Recognize income in a lower tax bracket, and
• Convert at a lower asset value, paying tax on a smaller amount while allowing the recovery to happen inside the Roth.

“Chunking” across multiple years

Instead of converting a large balance all at once, you can break it into chunks.

Example:

• You have $300,000 in a Traditional IRA and want it all in Roth over time.
• You convert $150,000 in 2025 and $150,000 in early 2026.
• That splits the taxable income into two years and may keep you out of the very top brackets in either year.

The main year-end question:

Do I want this conversion to land on my 2025 return, or should I deliberately push it into 2026, or do I chunk it across multiple years. For example, if you use a single filer making $150K you are in a 24% tax bracket, but if you converted $100K you’d have a majority of the conversion taxed at 32%. Instead you could convert 50K in 2025 which would still be taxed at 24% – and then convert the other 50K in 2026 where you’ll stay taxed at only 24% assuming your 2026 income is about the same. This timing saves about 8% on 50K and $4K in federal tax savings

3. Backdoor Roth IRA: Year-End Income Check

For high earners, the backdoor Roth IRA is how you effectively get money into a Roth IRA while being over annual MAGI limits.

For 2025, the logic is:

• If your income is under the Roth limits, you can make a regular Roth IRA contribution
• If your income is over the Roth limits, you should use the backdoor (Traditional IRA contribution + Roth conversion)

Key 2025 income points:

• Single: Full regular Roth contribution not allowed once you’re over $150,000 MAGI
• Married filing jointly: Full regular Roth contribution not allowed once you’re over $236,000 MAGI

If you’ll be over those numbers for 2025, the pattern is:

1. Contribute up to $7,000 to a Traditional IRA for 2025 (or $8,000 if you’re 50+).
2. Do not take a deduction for it—treat it as a nondeductible contribution. This is done on your personal tax return using IRS form 8606
3. Convert to Roth IRA (the backdoor step). No tax on conversion because it was a non-deductible contribution

If you already made a regular Roth IRA contribution in 2025 and later discover you’re over the limits, you can usually fix it by:

• Recharacterizing the Roth contribution to a Traditional IRA by the 2025 tax filing deadline, and then
• Converting it to Roth.

So year-end is about knowing where your 2025 income will land, so you don’t end up with an excess Roth contribution that has to be unwound.

4. HSA: Using the Last-Month Rule

Health Savings Accounts (HSAs) are one of the most powerful long-term tools available:

• Contributions are tax-deductible
• Growth is tax-deferred
• Withdrawals for qualified medical expenses are tax-free

For 2025:

• Self-only HSA contribution limit: $4,300
• Family HSA contribution limit: $8,550
• Age 55+ catch-up: $1,000

The last-month rule makes year-end important if you’re new to HSA-eligible coverage:

• If you are covered by an HSA-eligible high deductible health plan (HDHP) as of December 1, 2025, you’re treated as eligible for the entire year.
• That means you can still make the full 2025 HSA contribution, even if you weren’t covered all year.
• You must then stay HSA-eligible through all of 2026, or some of that contribution can become taxable.

If you just moved to a qualifying plan late in the year, this rule is worth knowing before December 31, as it allows a full year contribution even though you only had partial qualifying plan coverage.

5. Solo 401(k) Owners: Setup vs. Funding

If you’re self-employed with no full-time W-2 employees (other than you, partners, or certain family), a Solo 401(k) can be one of the most powerful retirement structures available.

The deadlines break down into two categories:

Existing Solo 401(k) plans

If your Solo 401(k) is already in place:

• 2025 contributions can be made up to your business tax return deadline, including extensions:
  • S-Corp / LLC taxed as S-Corp:
    • March 15, 2026 (original), or
    • September 15, 2026 (with extension)
  • Sole proprietor (Schedule C):
    • April 15, 2026 (original), or
    • October 15, 2026 (with extension)

However, if you’re an S-Corp owner, your employee deferral amount (Traditional or Roth) must be properly reflected on your 2025 W-2, which is due by January 31, 2026.

New Solo 401(k) plans

If you want a Solo 401(k) for 2025 and you’re starting from scratch, the safest approach if you want full flexibility is to:

• Adopt the plan by December 31, 2025

That keeps the rules simple and allows you to use both employee and employer contributions—potentially over $70,000 of 2025 contributions, depending on your income. You can set up a new Solo401(k) in 2026 and still 2025 contributions by the 2025 tax return deadline (plus extensions), but your ability to max out contributions is limited

6. IRA Contributions: Your True Last Chance

Unlike 401(k) contributions at work, IRA contributions for 2025 are not tied to December 31.

You can contribute to:

• A Traditional IRA,
• A Roth IRA (if you’re under the income limits), or
• A Traditional IRA as part of a Backdoor Roth

Up to the 2025 IRA contribution deadline: April 15, 2026.

A key reminder:

• Extending your individual tax return does not extend the IRA contribution deadline. April 15 is still the last day to make 2025 IRA contributions, even if you file later.
  

7. What Changes in 2026? New Limits and a Big Roth Rule

On top of all the year-end planning, several important changes kick in for 2026.

Higher IRA and 401(k) limits:

For 2026:

• IRAs (Traditional + Roth)
  • Base contribution limit: $7,500
  • Age 50+ catch-up: $1,100
  • Total if 50+: $8,600
• 401(k) / 403(b) / most 457 / TSP
  • Employee deferral limit: $24,500
  • Total 401(k) contribution limit (employee + employer + certain after-tax): $72,000

If you use automatic payroll or bank transfers, you’ll want to update those amounts for 2026 so you fully capture the higher limits.

Super catch-up for ages 60–63 (Began in 2025)

There is a special “super catch-up” for people aged 60 to 63:

• Standard catch-up (50+): $8,000 in 2026
• Super catch-up (ages 60–63): $11,250

Those four years can be a powerful window to accelerate your final push into retirement accounts.

Forced Roth catch-up for high earners (401(k) only)

A big structural change arrives in 2026 for 401(k) catch-up contributions:

• If you are age 50+ and your W-2 wages from that employer exceed $150,000 (based on the prior year), your 401(k) catch-up contributions must be Roth.
• You cannot make pre-tax catch-up contributions if your prior-year W-2 from that employer was over $150,000.

A few important points:

• The $150,000 test is based on your individual W-2, not your spouse’s income or joint MAGI.
• Your 2025 W-2 determines whether your 2026 catch-up must be Roth.
• The rule applies broadly to employer plans like 401(k), 403(b), and most 457 plans.

It does reduce the ability to grab one more chunk of tax deductions at the top end—but it also forces more dollars into Roth, where future growth and distributions at 59.5 are completely tax-free.

Putting It All Together

Here’s the practical way to use this:

• Before December 31, 2025, focus on:
  • Maximizing your 401(k) match and any year-end deferrals
  • Cleaning up Backdoor Roth IRA vs. regular Roth decisions based on 2025 income
  • Taking advantage of HSA last-month eligibility
  • Adopting any new Solo 401(k) you want in place for 2025
  • Deciding whether any Roth conversions should land in 2025 or be pushed into 2026
• Between January and April 15, 2026, focus on:
  • Final 2025 IRA contributions
  • Fixing any Roth income-limit issues with recharacterizations
  • Funding Solo 401(k)s by business return deadlines

And in parallel, start planning your 2026 savings strategy around:

• The higher IRA and 401(k) limits
• The super catch-up window at ages 60–63
• The forced Roth catch-up rules if you’re 50+ and earning over $150,000 from your employer

Successful retirement savers, those with the largest account balances, know how to get the most out of these rules and take advantage of of every tax-advantaged savings tool the IRS allows. These tips are a focused checklist on what to do now and what to do by April 15, 2026 so that you can maximize your tax-advantaged savings. This means more money working for you and less going to the IRS.