The word Roth can appear in a contribution election, a conversion of an existing balance or a withdrawal. Those transactions answer different questions. Identify the transaction first, then ask the TSP and your tax adviser which rules and records apply.
This guide complements the TSP overview and the pay-period contribution worksheet. It does not determine whether a conversion, a Roth contribution or a particular withdrawal is suitable for you.
Start with the transaction you are considering
| Transaction | What you need to distinguish |
|---|---|
| New traditional employee contribution | The tax treatment of money coming from current pay. |
| New Roth employee contribution | An after-tax employee contribution, subject to the shared employee contribution limit. |
| Roth catch-up contribution | Catch-up classification and any applicable payroll requirement, rather than a transfer of old account money. |
| Roth in-plan conversion | Moving an eligible existing traditional TSP balance into the Roth TSP balance. |
| Withdrawal or distribution | Taking money from the account, with tax treatment depending on the balance, payment and applicable qualification rules. |
| Rollover to another plan or IRA | A transfer with receiving-account, eligibility and tax questions that need their own review. |
Changing the tax treatment of future payroll deductions does not itself convert the existing traditional balance. Equally, converting an existing balance does not answer how future employee deductions should be elected.
What changed for in-plan conversions in 2026?
The TSP's official announcement says Roth in-plan conversions became available on January 28, 2026 through My Account. It identifies active participants, separated or retired participants and spouse beneficiary participants with eligible traditional balances. The eligible-balance conditions still matter; the existence of the option does not establish that a particular amount can be converted.
The announcement says a conversion of pre-tax traditional money adds that conversion amount to taxable income for the year. It also says the tax must be paid using personal funds from another source rather than from the amount being converted. That cash requirement belongs in the decision before a request is submitted.
The TSP recommends consulting a tax adviser. A useful review should consider the applicable tax year, the proposed amount, other income, the source of the tax payment and possible interactions with income-based costs or benefits. A website illustration cannot establish your tax bracket, Medicare-related charges or eligibility for another program.
Ask which Roth qualification rule applies
A Roth label alone does not establish that every future distribution will be tax-free. Contributions, earnings and converted amounts can raise different questions about qualification, timing and tax reporting. Ask which starting date or holding-period record applies to the particular TSP transaction and whether moving to a receiving account would change the analysis.
Keep these questions separate from investment performance. Selecting Roth treatment changes a tax classification; it does not guarantee a return, prevent losses or identify the appropriate fund. The amount available for retirement still depends on contributions, withdrawals, market results and other account activity.
Use a before-and-after review sheet
Write down the current traditional and Roth categories from your own records, the transaction proposed, the year in which it would be processed and the records needed afterward. Leave room for the TSP's eligibility determination and the tax adviser's explanation. Keep account numbers and tax returns within the official or professional process you have verified.
For a conversion discussion, useful questions include:
- Which balance is eligible, and are any amounts restricted from conversion?
- In which year would the transaction be reported?
- What cash outside the converted amount would be needed to meet tax obligations?
- Which tax forms and account records should reconcile after processing?
- What happens if a requested transaction has not finished by the expected date?
- Would a smaller transaction, a different year or leaving the balance unchanged need comparison?
These are alternatives to assess with qualified help, not an instruction to choose one of them. Do not submit a second request merely because the first result is not yet visible; verify its status through My Account or a TSP contact route you independently confirmed.
Keep withdrawals and rollovers in the same conversation
The TSP describes flexibility in choosing traditional or Roth balances for certain retirement distributions. A choice about which balance to use should also consider any required minimum distribution, the nature of the payment and the applicable tax reporting. Review the RMD and withholding checkpoints for that part of the process.
A rollover adds another plan's rules. Before assuming that a TSP tax result follows the money unchanged, compare the receiving account and its rules using the TSP-to-IRA decision worksheet.
What should the review produce?
Aim for a written explanation of the proposed transaction, the unresolved eligibility or tax questions, who will answer them and the record expected after completion. Keep the explanation and the account confirmation together. This supports a deliberate decision without asking a general inquiry form to collect your balance, income, medical information or tax documents.
Browse federal benefits, retirement and insurance topics or read how we prepare and check our guides.
Sources
- TSP: Roth in-plan conversions available, checked November 3, 2026
- TSP: Let’s talk taxes—and choosing between withdrawal options, checked November 3, 2026
- eCFR: 5 CFR Part 1650 - Methods of Withdrawing Funds from the Thrift Savings Plan, checked November 3, 2026
Have questions about your own situation? We'd be glad to help. Request a call. It's free, and there's never any obligation.