Roth in-plan conversions for your TSP

By TSP.gov     April 2026

As of January 2026, the Thrift Savings Plan (TSP) allows those with a traditional (pre-tax) balance in their TSP account to convert money to their Roth (after-tax) balance in their TSP account. This is called a “Roth in-plan conversion.” If you don’t have a Roth balance in your TSP account, your first Roth in-plan conversion will create one.

When you convert pre-tax money from your traditional TSP balance, your Roth in-plan conversion amount will become part of your taxable income for the year. This means that you’ll pay income tax on the conversion amount based on your income tax rate. You must pay the income tax on the conversion amount using personal funds from another source, such as a savings account. You cannot use part of the conversion amount in your TSP account to pay taxes.

A Roth in-plan conversion lets you move money from your traditional (pre-tax) balance to your Roth (after-tax) balance within your TSP account. You can do this any time during your working years and in retirement as long as your traditional TSP balance meets eligibility requirements.

There’s no TSP fee to convert money to Roth, but the amount you convert is added to your taxable income for the year. This could raise your tax bill more than you expect. How much you owe depends on the size of your conversion and your tax bracket.

Finally, keep in mind that a Roth in-plan conversion cannot be reversed or changed. Deciding whether to convert involves educated guessing about your future tax rate and income, and it has an immediate effect on your taxes. Before you make a decision you can’t undo, we strongly recommend that you consult a tax advisor to start planning how it would affect your taxable income and estimate how much you may need to pay in taxes.

To learn more about Roth in-plan conversions, read the TSP booklet, Tax Rules about TSP Payments and general information about traditional and Roth on the TSP website. You can also find a list of questions to ask yourself—and explanations about why they matter—in the TSP booklet Roth In-Plan Conversions.