Roth vs Traditional IRA: Which Is Better for Taxes?

Traditional IRA contributions go in pre-tax, which means you get a deduction now and pay ordinary income tax on every dollar you withdraw later, including the growth. Roth contributions go in after-tax, so there’s no deduction today, but qualified withdrawals in retirement are completely tax-free. The decision boils down to a bet: do you expect your tax rate to be higher now, while you’re working, or higher later, once Social Security, pensions, and RMDs are all stacked on top of each other? Most people guess lower-later. That guess isn’t automatically right.

A traditional balance doesn’t sit still waiting for you to decide when to pay tax on it. Required minimum distributions force withdrawals starting at 73 or 75 depending on your birth year, and that income arrives whether or not you want it that year. It can also push more of your Social Security benefit into taxable territory and trigger a Medicare IRMAA surcharge two years later. A Roth IRA has none of that — no RMDs during your lifetime, and withdrawals never touch your taxable income or your Medicare premium calculation.

Traditional accounts make more sense for someone in a high tax bracket today who genuinely expects to drop into a lower one in retirement — a high earner in their peak working years, for example. Roth accounts tend to win for people early in their career in a low bracket, for anyone who wants to leave a tax-free inheritance, and for retirees who want flexibility to pull income without disturbing their tax bracket or their Medicare premium. Many households end up holding both, which isn’t indecision — it’s what lets you choose which bucket to draw from depending on what the rest of your tax picture looks like that year.

You’re not locked into the choice you made decades ago. A Roth conversion moves traditional dollars into a Roth account, with the converted amount taxed as ordinary income in the year you do it. The years between retiring and starting Social Security or RMDs are often the cheapest window to convert, because income — and the tax rate on it — tends to be lower before those other sources kick in. Converting too much in one year can shove you into a higher bracket or straight into an IRMAA threshold, so the size of the conversion matters as much as the decision to do it.