Squeeze more Roth space out of your 401(k).
Enter what you and your employer already put in, and see how much after-tax room is left for a mega backdoor Roth — with 2026 IRS limits built in.
Give your Roth a number.
Enter your salary, your 401(k) contributions, and your employer's match to see your mega backdoor room.
YOUR MEGA BACKDOOR ROOM
$0
How full is your 401(k)?
Your contributions and your employer's, measured against the 2026 total limit.
$0 used$0 ceiling
Your action checklist
The mega backdoor only works if your plan allows after-tax contributions. Confirm each step with your plan administrator.
- 1
Check: does your plan allow after-tax contributions?
Not all 401(k) plans do. Ask HR or your plan administrator — if the answer is no, the mega backdoor is off the table.
- 2
Contribute after-tax up to your room
Put in up to your after-tax room as non-Roth after-tax contributions. This is separate from your $24,500 elective limit.
- 3
Convert to Roth inside the plan, fast
Ask for an in-plan Roth conversion of the after-tax money. Many plans offer automatic daily conversions — use it. Any earnings before the conversion are taxable, so speed matters.
- 4
Watch for plan-specific caps
Highly compensated employees can face nondiscrimination (ACP) testing limits. And some plans cap after-tax contributions below the IRS ceiling.
Limit details
- Annual salary
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- Your elective contributions
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- Elective limit (2026)
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- Employer contributions
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- Total annual-additions limit
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- After-tax room
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- Room per month
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