Roth Conversions for Federal Employees: A Tax-Smart Strategy

What Is a Roth Conversion and Why Does It Matter?

A Roth conversion is the process of moving money from a traditional (pre-tax) retirement account — such as a traditional IRA or traditional TSP — into a Roth IRA, where it can grow and be withdrawn tax-free. The catch is that you must pay income tax on the converted amount in the year of the conversion. In effect, you are choosing to pay taxes now at a known rate rather than paying taxes later at an unknown rate.

For federal employees and retirees, Roth conversions can be one of the most powerful tax planning strategies available. The reason is straightforward: most federal retirees have the majority of their retirement savings in pre-tax accounts (traditional TSP and traditional IRA), and every dollar they withdraw from those accounts is taxed as ordinary income. Without planning, a federal retiree with a FERS pension, Social Security, and required minimum distributions from a large TSP or IRA balance can find themselves in a surprisingly high tax bracket throughout retirement.

Roth conversions, executed strategically, can reduce that lifetime tax burden significantly.

The Mechanics of a Roth Conversion

The basic process is straightforward:

1. Move funds from a traditional IRA (or rolled-over TSP) to a Roth IRA at the same brokerage. Most custodians handle this as a simple internal transfer.
2. Report the converted amount as ordinary income on your tax return for the year. The custodian will issue a Form 1099-R.
3. Pay the resulting tax from non-retirement funds. This is important — if you use the converted funds themselves to pay the tax, you lose that portion of retirement savings and may also owe a 10% early withdrawal penalty if you are under 59½.
4. Satisfy the five-year rule: Each Roth conversion has its own five-year clock. Earnings on converted amounts are not tax-free until the funds have been in the Roth IRA for five years and you are at least 59½. However, you can always withdraw the converted principal (the amount you paid tax on) without additional tax or penalty.

Important note on TSP: You cannot convert funds directly within the TSP — there is no option to move money from traditional TSP to Roth TSP. To do a Roth conversion with TSP funds, you must first roll the traditional TSP balance (or a portion of it) into a traditional IRA, and then convert from the traditional IRA to a Roth IRA. This means Roth conversions are most practical for separated or retired federal employees who can roll over their TSP. Active employees can only roll over funds from previous employer plans that were moved into TSP, not their current FERS contributions.

When Roth Conversions Make the Most Sense

The key principle behind Roth conversions is converting when your tax rate is low so you avoid paying taxes at a higher rate later. For federal employees and retirees, several windows of opportunity exist:

The gap years between retirement and Social Security: If you retire at your MRA (age 55-57) or at age 60 with 20 years of service, you may have several years before Social Security begins at age 62 (or later if you delay). During these years, your taxable income may consist primarily of your FERS pension and possibly the Special Retirement Supplement. This is often a lower-income period compared to your working years or your later retirement years when Social Security and RMDs kick in. Converting traditional IRA funds to Roth during this window lets you fill up the lower tax brackets at 10%, 12%, and 22% rates.

The gap between Social Security and RMDs: Even after claiming Social Security, the period before required minimum distributions begin (age 73 under current law) may offer conversion opportunities if your combined income is still below the bracket thresholds where you'll land once RMDs begin.

Years with unusually low income: Sabbaticals, extended leave, or the first partial year of retirement can create one-time windows for advantageous conversions.

Before tax rates increase: The Tax Cuts and Jobs Act's individual rate reductions are scheduled to sunset. If rates revert to pre-2018 levels, converting now at today's lower rates could be advantageous.

How Much Should You Convert Each Year?

The optimal conversion amount depends on your specific tax situation, but the general strategy is to "fill up" tax brackets from the bottom without unnecessarily pushing into a higher bracket.

For example, if you are a retired federal employee filing jointly with a FERS pension of $40,000 and no other taxable income, the 2026 standard deduction of approximately $32,300 would reduce your taxable income to about $7,700. The 10% tax bracket covers the first $23,850 of taxable income for married filing jointly, and the 12% bracket covers income up to approximately $96,950.

In this scenario, you could convert roughly $89,250 ($96,950 minus $7,700) and stay within the 12% bracket, paying just $10,710 in federal tax on the conversion. The same $89,250 withdrawn as RMDs in a later year — when stacked on top of Social Security and pension income — might be taxed at 22% or even 24%, costing thousands more.

Key thresholds to monitor when planning conversion amounts:

• Social Security taxation thresholds: At certain combined income levels, up to 85% of your Social Security benefits become taxable. Conversions can push you above these thresholds.
• Medicare IRMAA surcharges: If your modified adjusted gross income exceeds certain levels, you pay higher Medicare Part B and Part D premiums two years later. A large conversion in one year can trigger IRMAA surcharges.
• Net Investment Income Tax (NIIT): The 3.8% surtax applies to investment income when MAGI exceeds $250,000 for married filing jointly.

The Backdoor Roth Strategy

High-income federal employees who exceed the Roth IRA contribution income limits can still get money into a Roth IRA using the "backdoor" strategy:

1. Contribute to a traditional IRA (non-deductible if your income is too high for a deduction)
2. Convert the traditional IRA to a Roth IRA shortly afterward
3. Pay tax only on any gains that occurred between the contribution and conversion (usually minimal if done quickly)

The pro-rata rule complication: If you have existing pre-tax money in any traditional IRA (including SEP-IRA or SIMPLE IRA), the IRS treats all your traditional IRAs as one pool for conversion purposes. You cannot selectively convert only the non-deductible (after-tax) portion. The taxable percentage of your conversion is based on the ratio of pre-tax to after-tax money across all your traditional IRAs.

The workaround: roll any existing pre-tax traditional IRA funds into your TSP (if you are still an active employee) or an employer plan before executing the backdoor Roth. This removes the pre-tax funds from the IRA pool and allows you to convert only the non-deductible amount.

Common Mistakes to Avoid

• Converting too much in one year: A massive conversion can push you into the 32% or 37% bracket, trigger IRMAA surcharges, and increase Social Security taxation. Spreading conversions over multiple years is almost always better.
• Paying taxes from the converted funds: This reduces the amount that ends up in your Roth and may trigger early withdrawal penalties. Always pay the tax bill from a separate taxable account.
• Ignoring state taxes: Your state may tax Roth conversions as ordinary income. Some states have no income tax, which makes conversions even more attractive. If you plan to move to a no-income-tax state in retirement, you might delay conversions until after the move.
• Forgetting the five-year rule: Each conversion starts its own five-year clock. If you need to access converted funds before age 59½ and before the five-year period, the earnings portion may be subject to tax and penalty.
• Not coordinating with your overall plan: Roth conversions should be part of a comprehensive retirement income strategy that accounts for pension, Social Security, TSP/IRA withdrawals, and investment income. An isolated conversion decision without context can create unintended consequences.

Is a Roth Conversion Right for You?

Roth conversions are not universally beneficial. They tend to be most valuable for federal employees and retirees who:

• Have large traditional TSP or IRA balances that will generate significant RMDs
• Expect to be in a similar or higher tax bracket in retirement
• Have years of lower income available for conversions (especially the gap years)
• Want to reduce the tax burden on their heirs, since inherited Roth IRAs are not subject to income tax
• Believe tax rates will be higher in the future

Conversely, if you expect your retirement income to be significantly lower than your current income, or if you need the tax deduction from traditional contributions to manage your current cash flow, conversions may be less beneficial.

A qualified financial advisor can model your specific numbers and determine the optimal conversion strategy for your situation. The analysis should project your tax liability with and without conversions over your entire retirement, not just the current year.