#3316 · Finance Tool

Mega Backdoor Roth Withdrawal Schedule Calculator

Mega Backdoor Roth Withdrawal Schedule Calculator turns your planning assumptions into an actionable estimate of total projected withdrawals. Adjust the values to compare scenarios, then use the supporting figures to see what drives the result. The calculation is a planning aid, not a prediction, and it leaves rates and tax assumptions under your control.

Calculator

Enter your assumptions
$
years
%
$
%
years

How to use this calculator

  1. Enter the assumptions that describe your Mega Backdoor Roth plan.
  2. Use marginal tax rates rather than average tax rates where the field calls for them.
  3. Select Calculate to update the estimate.
  4. Review the main result together with the secondary figures and assumptions.

Formula

The contribution phase compounds annual additions. The withdrawal phase compounds the balance, then subtracts each year's inflation-adjusted withdrawal.

What the result means

The total is the sum of withdrawals the modeled balance can actually fund during the chosen period.

The model does not determine whether withdrawals are qualified or whether a plan permits the transactions assumed.

Example calculation

Contributing $30,000 for 15 years at 6% builds a projected balance of about $740,177 before the withdrawal phase begins.

Tips for better results

  • Confirm that your plan accepts after-tax contributions.
  • Check whether in-plan Roth conversions or in-service rollovers are available.
  • Convert after-tax money promptly to limit taxable earnings.
  • Count employer contributions when checking the plan limit.
  • Revisit contribution room after compensation changes.

Frequently asked questions

Does this schedule check whether my plan permits Mega Backdoor Roth transactions?

No. Confirm after-tax contribution and conversion features with the plan administrator.

When do withdrawals begin in the model?

They begin after the selected number of full contribution years.

What happens if the planned withdrawal is larger than the balance?

The final withdrawal is capped at the remaining balance and the depletion year is reported.

Are qualified Roth withdrawals assumed tax-free?

The cash-flow projection does not subtract tax, but it also does not determine whether a withdrawal is qualified.

Can withdrawals rise with inflation?

Yes. Use the annual withdrawal increase field as an inflation or spending-growth assumption.

Two-phase schedule

PhaseCash flow
AccumulationAnnual contribution plus growth
WithdrawalAnnual growth, then planned distribution

Browse calculator categories

22 category hubs