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Traditional vs Roth IRA: The Math
Contribute $7,000 a year for 30 years and the traditional-vs-Roth IRA math question is worth roughly $60,000 in lifetime tax, not pocket change. Both accounts grow tax-free along the way; the entire fight is about which year the IRS takes its cut.
Traditional: deduct now, pay ordinary income tax on every withdrawal later. Roth: pay tax now, withdraw everything tax-free after 59½ and the five-year rule. Same $7,000, same market return, opposite sides of the tax timeline.
The Breakeven Question
Everything reduces to one comparison: your marginal tax rate today versus your effective rate in retirement. Contribute $7,000 at a 24% marginal rate and it costs $5,320 after tax in a Roth, or $7,000 in a traditional IRA with a $1,680 deduction. If your retirement effective rate lands under 24%, traditional wins. Above it, Roth wins. Most retirees land in the 12% to 18% effective range, which is why the textbook answer favors traditional for peak earners and Roth for everyone earlier in a career.
Two Distortions People Miss
Effective size. $7,000 in a traditional IRA is the government's money in part; roughly $1,680 of a withdrawal belongs to the Treasury at a 24% rate. A $7,000 Roth contribution is entirely yours. Savers who contribute the max to both are actually putting away different after-tax amounts, which is why many planners contribute the traditional max plus the tax refund to a Roth.
Required distributions. Traditional IRAs force withdrawals from age 73 under RMD rules, pushing taxable income up exactly when Social Security becomes up to 85% taxable. Roth IRAs have no lifetime RMDs for the original owner, which keeps future brackets flexible and leaves a larger tax-free inheritance.
A Concrete Two-Path Example
Dana, 38, in the 22% bracket, saves $7,000 a year for 29 years at 6.5%. Both paths reach roughly $735,000. In the traditional version, withdrawals are taxed as income — call it $80,000 a year of withdrawals with an effective tax near 14%, about $11,200 a year to the IRS. In the Roth version, the same $80,000 costs nothing. Over a 25-year retirement that spread approaches $280,000. Dana's counterfactual: if she had been in the 32% bracket while saving and dropped to 12% in retirement, traditional would have won by a similar margin. The account follows the bracket, not the other way around.
This article is general educational information only, not financial, tax, investment, accounting, or legal advice, and is not a recommendation to buy, sell, or hold any product or security. Figures reflect published IRS, HMRC, and Social Security Administration guidance for 2026 and are subject to change and annual indexing; always confirm current thresholds with the official source before acting. Rules differ by country, state, and personal situation, and nothing here creates a fiduciary or advisory relationship. This site is supported by advertising, which does not influence our editorial conclusions. For any decision with real financial consequences, consult a licensed fiduciary advisor or tax professional.