Every personal finance article about Roth vs Traditional IRA ends the same way: "It depends on your situation." Which is technically true and practically useless.
So I did what apparently nobody else wants to do. I built a spreadsheet, plugged in six different real-world scenarios, and ran the numbers forward 20, 30, and 40 years. The results were not what I expected.
Disclaimer: This article is for educational purposes only and does not constitute financial advice. Consult a qualified financial advisor before making investment decisions. Tax laws vary and may change. Sources: IRS.gov, Vanguard research.
The 60-Second Refresher
Traditional IRA: Contribute pre-tax dollars. Money grows tax-deferred. Pay income tax on withdrawals. Tax break today, tax bill later.
Roth IRA: Contribute after-tax dollars. Money grows tax-free. Zero tax on withdrawals. Tax bill today, freedom later.
Both have a $7,000 annual limit in 2026 ($8,000 if 50+). The difference is entirely about when you pay taxes.
Scenario 1: The 25-Year-Old Software Developer ($85K)
Sarah is 25, earns $85,000, 22% bracket. Plans to retire at 65.
Traditional: $7,000 pre-tax saves $1,540 today. After 40 years at 7% = $1,049,740. At 22% retirement tax = $818,797.
Roth: Same growth = $1,049,740 completely tax-free.
Winner: Roth by $230,943. At 25, forty years of tax-free growth crushes the upfront savings.
Scenario 2: The 45-Year-Old Teacher ($62K)
Mark is 45, earns $62,000, 22% bracket now. Expects 12% in retirement (pension + Social Security).
Traditional: 22 years at 7% = $319,793. At 12% = $281,418.
Roth: $319,793 tax-free.
Winner: Roth by $38,375. Even with a lower retirement bracket, Roth wins — but the margin is much smaller (13.6%).
Scenario 3: The 35-Year-Old Business Owner ($150K, Variable)
Lisa earns $150K this year but income fluctuates. At $150K, she may not qualify for a deductible Traditional IRA. Her option: non-deductible Traditional or backdoor Roth.
Winner: Backdoor Roth, no question. A non-deductible Traditional gives the worst of both worlds — no upfront deduction AND taxable withdrawals.
Scenario 4: The 55-Year-Old Pre-Retiree ($95K)
David is 55, retiring at 62. Seven years of contributions. 22% now, expects 18% in retirement.
Traditional: $8,000/yr catch-up, 7 years = $68,578. At 18% = $56,234.
Roth: $68,578 tax-free.
Winner: Roth by $12,344. Plus Roth has no Required Minimum Distributions at 73 — a hidden benefit that makes it even more valuable.
Scenario 5: High-Tax State to No-Tax State ($70K)
Emma lives in California (31% combined rate), plans to retire in Texas (0% state tax).
Traditional: 35 years = $738,741. At 18% federal only = $605,768.
Roth: $738,741 tax-free, but she paid 31% on contributions.
Winner: Traditional by $41,283. The ONE scenario where Traditional wins clearly. The 13-point rate gap is large enough to overcome Roth advantage.
Scenario 6: Married Couple, Both 35 ($140K Combined)
Alex contributes to Roth. Jordan contributes to Traditional. This gives tax diversification — pull from Traditional in low-income years, Roth in high-income years.
Winner: The split strategy. Having both account types gives flexibility that neither alone provides.
The Verdict
- Roth wins in 4 out of 6 scenarios
- Traditional wins only with a significant tax rate drop (high-tax to no-tax state)
- The split strategy is underrated
- Younger = more Roth advantage (time amplifies tax-free growth)
The biggest surprise: even when Traditional "wins," the margin is slim. When Roth wins, it wins big. That asymmetry matters.
Sources: IRS Publication 590-A/B (2026), Vanguard retirement research (2025), Tax Foundation data.