What Is a Backdoor Roth IRA? A 2026 Step-by-Step Guide
A backdoor Roth IRA lets high earners fund a Roth IRA despite income too high to contribute directly. Done cleanly, it is a simple two-step move, but the pro-rata rule can make most of it taxable.
Key takeaways
- Not a special account: a nondeductible IRA contribution, then a Roth conversion.
- 2026 limit $7,500 ($8,600 at 50+); direct Roth contributions phase out above $153,000 single, $242,000 joint.
- Conversions have no income limit: why the strategy exists.
- The pro-rata rule taxes conversions proportionally if you hold pre-tax IRA money at year-end.
- Report it on Form 8606; leave converted money five years if under 59½.
What a backdoor Roth IRA is, and why it exists
A backdoor Roth IRA combines two legal transactions: a nondeductible traditional IRA contribution (after-tax, no deduction claimed), then a conversion to a Roth IRA, where it can grow and come out tax-free if withdrawal rules are met. No account is officially called this; the name describes the route. Fidelity’s explainer covers the same two steps.
The route exists because contributions and conversions are treated differently. Direct Roth contributions phase out by income: for 2026, $153,000–$168,000 single and heads of household, $242,000–$252,000 joint, per the IRS announcement of the 2026 limits. Conversions have no income limit, so a high earner barred from contributing directly can still reach a Roth IRA (see our Roth vs. 401(k) comparison).
The 2026 limits that decide whether you need one
For 2026, the IRS raised the combined IRA limit to $7,500 (from $7,000 in 2025), plus a $1,100 catch-up at 50 or older, for $8,600 total. It covers all your IRAs combined and cannot exceed taxable compensation, so a $7,500 backdoor contribution uses your entire IRA room. Many users get no deduction: for 2026 it phases out at $81,000–$91,000 single (workplace-plan covered) and $129,000–$149,000 joint (contributing spouse covered), per IRS Publication 590-A sets out. Above those ranges, contributions are nondeductible; that after-tax “basis” is what Form 8606 tracks.
| Feature | Direct Roth contribution | Backdoor Roth IRA |
|---|---|---|
| Income limit | Phases out: $153,000–$168,000 single, $242,000–$252,000 joint | None on conversion |
| 2026 amount | Up to $7,500 ($8,600 at 50+) | Same cap, shared across IRAs |
| Paperwork | None extra | Form 8606 yearly |
The step-by-step process
First check: taxable compensation and any pre-tax balance in a traditional, SEP, or SIMPLE IRA.
- Contribute to a traditional IRA. Make a nondeductible contribution up to the limit; claim no deduction.
- Let the funds settle. No IRS-mandated wait, but let it clear; earlier earnings are taxable, so convert promptly.
- Convert to your Roth IRA. It is taxed in the year it happens, even if the contribution was for the prior tax year.
- File Form 8606. Part I reports contribution and basis; Part II, the conversion. Keep the form, 1099-R, and confirmations: your provider does not track basis.
Deadlines differ: a 2026 contribution can be made until April 2027, but a conversion counts in its year. A retirement planning tool can help track the years and basis.
The pro-rata rule: the trap that taxes most conversions
On conversion, you cannot pick out just after-tax dollars: the IRS treats all your traditional, SEP, and SIMPLE IRAs as one pot, taxing every conversion in that pot’s proportion. Employer plans such as a 401(k) are excluded, so some people roll pre-tax IRA money into a workplace plan, if allowed, before December 31. Example:
- 2026 nondeductible contribution: $7,500 basis.
- Pre-tax rollover IRA (illustrative): $67,500; total pot $75,000.
- Nontaxable share: $7,500 ÷ $75,000 = 10%.
- Convert $7,500: $750 (10%) tax-free, $6,750 (90%) taxable.
- Basis carried forward: $7,500 − $750 = $6,750.
Instead of a nearly tax-free conversion, 90% was taxable, and most basis stayed behind. Check December 31 balances first. If the taxable share would be large, pause, clear the pre-tax balance, or skip that year.
The two 5-year rules, kept separate
Two five-year clocks apply. The first governs tax-free earnings: a distribution is “qualified,” and fully tax-free, only after the five-tax-year period from the first year you funded any Roth IRA, as IRS Publication 590-B explains, plus a condition such as reaching 59½. A new Roth IRA for a conversion does not restart it. The second runs per conversion from January 1 of the conversion year: withdraw the taxable part within five years while under 59½, and you generally owe 10% additional tax, despite tax already paid at conversion. After 59½, it no longer matters.
Common pitfalls to avoid
December 31 timing. The test looks at year-end, not conversion day. A November rollover of a pre-tax 401(k) into an IRA can make a spring conversion mostly taxable.
Forgetting Form 8606. Without it, the IRS has no record of your basis, and you risk double taxation.
Double-counting the deduction. You cannot both deduct a contribution and convert it tax-free.
State tax and required distributions. Some states tax conversions differently; check yours first. A required minimum distribution must be taken before converting: it cannot itself be converted.
Who should not use a backdoor Roth
Skip it with a large pre-tax IRA balance and no workplace plan that accepts a rollover to clear it: the pro-rata rule will tax most of each conversion. It is also unnecessary if you can contribute directly: simpler, no Form 8606, no conversion tax. Skip it with no taxable compensation that year, or if under 59½ and you may need the money within five years. If you will not keep the paperwork, do not start: Form 8606 must prove which dollars were already taxed. Once inside, our investment strategies guide and retirement calculator can help next.
What about the mega backdoor Roth?
The mega backdoor Roth is a different, employer-plan strategy, not a bigger version of this one: after-tax 401(k) contributions, where allowed, plus an in-plan Roth conversion, moving far more than the IRA limit, if your plan permits both steps. Self-employed readers: see our solo 401(k) guide separately.
This article is general US information, not tax advice. Tax rules change, and the right move depends on your income, existing balances, and plans for the money. Before your first backdoor Roth with pre-tax IRA money, ask a tax professional to run the calculation on your actual balances.