Backdoor and mega-backdoor Roth math, with the pro-rata rule.
Covers: backdoor roth, mega backdoor, pro rata, after-tax 401k, roth conversion, 590-a.
Open the Backdoor Roth tool →When your income is too high to contribute to a Roth directly, two moves get money in anyway. The backdoor: contribute to a traditional IRA without deducting it, then convert it to a Roth. The catch is the pro-rata rule: if you hold any pre-tax IRA money, the IRS treats every conversion as a proportional mix of pre-tax and after-tax dollars, so part of it is taxable. With no pre-tax IRA balance, the conversion is tax-free.
The mega-backdoor uses after-tax 401(k) contributions: your plan's overall §415(c) limit minus your own deferrals and your employer's contributions is room you can fill with after-tax money and convert to Roth, but only if your plan allows after-tax contributions and in-plan conversions. The IRS limits here are read from the current-year notice and cited. This is information, not advice.
Free forever, with no account and no ads. Computed entirely on your device for U.S. taxes and benefits — nothing is ever sent anywhere. Educational information, not financial, tax, investment, or legal advice.