Roth Conversion Ladder Strategy for 2026

When is the best time to pay tax on your retirement savings? Almost never the year the IRS forces you to. A Roth conversion ladder is the plan for paying it on your terms instead: you move money from a traditional IRA to a Roth in measured slices across the years after you stop working and before required withdrawals start, deliberately filling the low tax brackets while they’re empty.

Why the window exists

A Roth conversion means moving money from a pre-tax account, where every future dollar is taxable, into a Roth, where it grows and comes out tax-free. You pay ordinary income tax on whatever you convert, in the year you convert it.

For a lot of retirees there’s a stretch, often the 60s, where income craters. The paycheck has stopped, Social Security hasn’t started, and RMDs haven’t kicked in yet at 73 or 75. Your taxable income may be the lowest it will ever be. That’s the window. Leave a big traditional IRA untouched and it keeps compounding into a larger forced withdrawal later, taxed at whatever bracket you’re in then, on top of Social Security.

How the ladder works in 2026

The idea is to convert just enough each year to “fill up” a target bracket without spilling into the next one. For 2026, a married couple filing jointly sits in the 22% bracket up to $211,400 of taxable income, where the 24% bracket begins. Many retirees aim to convert up to the top of the 22% or 24% bracket, year after year, turning future high-taxed dollars into Roth dollars at a known, moderate rate.

A simplified picture for a married couple:

• Estimate your taxable income for the year before any conversion.
• Pick your ceiling, say the top of the 22% bracket at $211,400.
• Convert the difference between your income and that ceiling.
• Pay the tax from a taxable account, not from the IRA, so the full amount keeps growing in the Roth.
• Repeat each year until RMDs begin.

That last point matters. If you pay the conversion tax out of the IRA itself, you shrink the very balance you’re trying to move, and you may owe a penalty if you’re under 59½.

The hidden price: the surcharge lines you can’t see on the bracket chart

Here’s where most do-it-yourself ladders go wrong. The tax bracket is not the only line you can cross. A conversion raises your income, and income two years later sets your IRMAA Medicare surcharge once you’re 65. It can also pull more of your Social Security into taxation and trip the investment-income surtax. So the real cost of a conversion isn’t just the bracket you’re filling. It’s the bracket plus the surcharges that fire above quiet thresholds you won’t find on a tax table. Convert with the whole board in view, not just the income-tax line.

For higher-net-worth households

With a large pre-tax balance, the goal isn’t to convert everything. It’s to convert enough that your future RMDs don’t rocket you into the top bracket and the top IRMAA tier for the rest of your life. The math leans harder toward converting when you expect your later bracket to be higher than today’s, when you can pay the tax from outside the IRA, and when a tax-free Roth is the asset you’d most want to leave heirs, since they inherit it without the income tax a traditional IRA carries. Delaying Social Security, covered in Social Security at 62 vs. 70, keeps the window open longer and gives the ladder more rungs.

The ladder isn’t a one-time trick. It’s a multi-year discipline of paying tax when it’s cheap so you’re not cornered into paying it when it’s not. Build it on purpose, a rung a year, and you control the bill instead of the bill controlling you.