Starting Jan. 28, 2026, TSP participants and spousal beneficiaries are able to convert money from a traditional balance to Roth within their TSP account. This transaction is called a “Roth in-plan conversion.”
When a participant converts money from their traditional TSP balance, the taxable Roth in-plan conversion amount will become part of the participant’s taxable income for the year. This means that they’ll pay income tax on the taxable conversion amount based on their income tax rate.
According to the TSP, “The main reason to consider a conversion is that it changes when you pay taxes. Here’s the trade-off: you pay taxes now on the amount you convert so that future growth and withdrawals from your Roth balance can be tax-free.”
TSP Roth in-plan conversions are complex and are irrevocable: Once the transaction is processed, the transaction cannot be reversed or changed. So it is important that any TSP participant have a good understanding of the conversions and their consequences, and are recommended to seek the advice of a tax advisor.
The TSP has launched a set of helpful tools to help TSP participants in making a decision if a TSP Roth In-Plan Conversion is right for them.
TSP Roth In‑Plan Conversion Calculator
This new TSP Roth In Plan Conversion calculator does not require login to a TSP participant’s My Account area.
Using the free online calculator will help a TSP participant answer these questions:
- Could paying taxes now on a Roth in-plan conversion lead to more money after taxes when you withdraw from your TSP account?
- Would you have more or less money in the future if you use personal funds outside your TSP account to pay taxes now on a Roth in-plan conversion instead of keeping or investing those personal funds?
To use this calculator effectively, TSP participants will need the following information:
- The amount of their traditional TSP balance that they want to convert to Roth ($500 minimum).
- Current and future estimated federal marginal tax rates
- Current and future estimated state or local tax rates. According to the TSP, Current state and local taxes range from 0% to 13.3%. These tax rates can usually be found on state or local government websites.
- An estimated rate of return for your investments.
To access this calculator go here.
My Account TSP Roth Conversion Calculator for Qualified TSP Participants
Those TSP participants who are eligible to perform a Roth in-plan conversion can use the My Account TSP Roth in-plan conversion calculator. This tool helps participants access a personalized version of the calculator and uses actual account data.
This calculator will:
Determine the tax consequences of converting
Give actual comparisons of using different conversion amounts
Display how conversion scenarios will affect Roth TSP vs. traditional TSP balances on a time line.
To use this calculator, login to your TSP My Account.
Eligibility for Roth in-plan conversions
TSP participants are eligible to do a Roth in-plan conversion if they have a vested traditional balance in a TSP account.
Roth in-plan conversions are available to all TSP participants:
- Active participants (current federal civilian employees and uniformed services members)
- Separated and retired participants
- Spouse beneficiary participants
Non-spouse beneficiaries are not eligible for Roth in-plan conversions.
TSP Guide to Roth In-Plan Conversions
The TSP’s new guide to the TSP Roth In-Plan Conversion Option provides details on:
- eligibility
- paying taxes
- how a conversion affects your TSP investments
- other important rules and considerations.
To download the guide (20-page PDF), go here.
Roth In-Plan Conversion My Account Tutorial Video
On Jan. 28, the TSP launched a new tutorial video to help TSP participants learn more about a TSP Roth in-plan conversion.
Specifically the video help participants:
- Step-by-step instructions of the process of how to complete one inside My Account
- What to expect during the process
Watch the video below:
