How this page is reviewed
See methodology, assumptions & sources
| Risk tier | YMYL |
|---|---|
| Author | Calculover Editorial Team Finance education |
| Editorial owner | Calculover Investing & Retirement Desk Retirement methodology owner |
| Reviewer | Calculover Editorial Review Source and limitation review |
| Last reviewed | 2026-06-21 |
| Last verified | 2026-06-21 |
| Data effective date | 2026-06-21 |
Methodology
Backdoor Roth vs Taxable Account: High-Earner Investing compares Backdoor Roth and Taxable Account using the figures you enter — including growth, 2026 amount you can add, annual tax drag, income limit — to show which option costs less, when each one is the better choice, and the break-even between them. The embedded calculators run your own numbers so the comparison reflects your situation, not a generic example.
Assumptions
- All rates, balances, contributions, and timelines are user-supplied; defaults are illustrative round numbers, not quotes.
- Regulatory figures cited (2026 IRS limits, tax brackets, and similar) reflect published federal values for the stated year.
- Results assume the inputs hold over the chosen horizon and do not model every individual circumstance.
Limitations
- This page does not predict future interest rates, returns, tax law, or prices, and is not a substitute for personalized professional advice.
- Fees, credit-tier pricing, eligibility rules, and state-specific differences can materially change the outcome for your situation.
Sources
- Retirement Plans, Internal Revenue Service
- Retirement Topics — IRA & 401(k) Limits, Internal Revenue Service
- Saving and Investing, Investor.gov (U.S. SEC)
Professional guidance: This page is for retirement-planning education only and is not investment, tax, or fiduciary advice. Confirm contribution limits, income rules, and tax treatment with a licensed financial professional.
Why high earners need a side door
In 2026 the ability to contribute directly to a Roth IRA phases out between $153,000 and $168,000 of modified AGI for single filers and between $242,000 and $252,000 for married couples filing jointly. Earn more than the top of your range and the front door is closed — you can't contribute to a Roth IRA directly.
The backdoor Roth is the legal workaround. There's no income limit on (1) making a nondeductible contribution to a traditional IRA, or (2) converting a traditional IRA to a Roth. Do both — contribute up to $7,500 (2026) to a traditional IRA, then convert it to Roth — and you've funded a Roth IRA regardless of income. Because the contribution was after-tax to begin with, the conversion itself usually generates little or no tax, and from then on the money grows and comes out tax-free.
Backdoor Roth vs taxable: the growth gap
Here's the key insight: a backdoor Roth and a taxable account both start with after-tax dollars. You've already paid income tax on the money either way. The difference is what happens to the growth.
In a taxable account, you owe tax every year on dividends, and you owe capital-gains tax whenever you sell at a profit — long-term gains run 0%, 15%, or 20% depending on income, plus a possible 3.8% net investment income tax for high earners. In a backdoor Roth, the growth is completely untaxed: no annual drag, no capital-gains bill, nothing when you withdraw after 59½. On the exact same contribution and return, the Roth ends with more money purely because the IRS never takes a cut of the gains. For a high earner facing the 15–20% long-term rate plus NIIT, that tax-free growth is a meaningful, compounding advantage — which is why the backdoor Roth almost always wins for money that fits inside the $7,500 limit.
The pro-rata rule — the one real trap
The backdoor Roth has a single serious pitfall: the pro-rata rule. The IRS treats all your traditional, SEP, and SIMPLE IRAs as one combined pot when you convert. If that pot holds pre-tax money, your conversion is taxed in proportion to the pre-tax share — you can't cherry-pick only the new nondeductible dollars.
Example: you make a $7,500 nondeductible contribution but already have $92,500 of pre-tax money in a rollover IRA. Your total IRA balance is $100,000, of which only 7.5% is after-tax. Convert $7,500 and the IRS treats 92.5% of it — about $6,940 — as taxable. The clean backdoor turns into a mostly taxable conversion. Two fixes:
- Roll pre-tax IRA money into your employer 401(k) if the plan accepts it. 401(k) balances aren't counted in the pro-rata calculation, so this empties the IRA pot and clears the path.
- Skip the backdoor and use a taxable account instead if you can't clear the pre-tax balance — a partly taxable conversion may not be worth the hassle.
A real example: $7,500/year for 25 years
Compare a high earner who backdoors $7,500 a year against one who invests the same $7,500 in a taxable account, both at a 7% return for 25 years.
The backdoor Roth grows to roughly $475,000, and every dollar comes out tax-free after 59½. The taxable account reaches a similar pre-tax balance, but a ~0.5% annual tax drag on dividends plus a 15–20% capital-gains bill at sale can quietly skim tens of thousands off the after-tax result — and a high earner may also owe the 3.8% NIIT. Same money in, materially more money out of the Roth, simply because the growth was never taxed. The taxable account still earns its place for anything beyond the $7,500 limit and for goals you'll fund before retirement. Model both with your own contribution and timeline in the calculators below.