TSP Strategy for Federal Employees

Fund choices, withdrawal sequencing, Roth vs. traditional, and the rollover decision — for federal employees who want to make the TSP work alongside a FERS annuity and Social Security.

The five TSP funds

TSP's simplicity is a feature. Five core funds, rock-bottom fees (0.05% expense ratio — about $5/year per $10,000 invested), and no fund-selection paralysis if you use a Lifecycle fund.

• G Fund (Government Securities): Treasury-rate return with no interest-rate risk — the only fund guaranteed not to lose nominal value. Ideal as a ballast for retirees drawing down.
• F Fund (Fixed Income Index): Bloomberg U.S. Aggregate Bond Index. Standard bond fund — duration risk included. Less defensive than G Fund in rising-rate environments.
• C Fund (Common Stock Index): S&P 500. Your primary equity growth engine — should be the largest equity holding for most federal employees building wealth.
• S Fund (Small Cap Stock Index): Dow Jones U.S. Completion Total Stock Market Index (everything outside the S&P 500). Historically higher long-run returns, higher volatility.
• I Fund (International Stock Index): MSCI EAFE (developed markets). Provides non-U.S. diversification. Note: MSCI recently added emerging markets to the I Fund benchmark — slightly more volatility than legacy I Fund.

Lifecycle (L) funds

L Funds are target-date funds built from the five core funds above. They automatically shift toward more conservative allocations as the target date approaches. If you have no strong view on allocation, L Funds are a reasonable default — pick the one closest to your anticipated retirement year.

Common mistake: choosing an L Fund based on your planned TSP withdrawal date rather than life expectancy. If you retire at 57 and expect to draw TSP through age 85, your time horizon is 28 years, not the 3 years to your target date. A more aggressive L Fund (or a manual split of C/S/I funds) may be appropriate if you have strong FERS annuity and Social Security income to cover living expenses.

Contribution strategy: maximize employer match first

FERS employees receive an automatic 1% agency contribution regardless of employee contributions, plus a dollar-for-dollar match on the first 3% and $0.50 on the dollar for the next 2%. To capture the full 5% agency contribution, contribute at least 5% of basic pay.

Once you're capturing the match, increase contributions toward the elective deferral limit. Priority order for contributions beyond the match: traditional TSP contributions (if you expect to be in a lower bracket in retirement), Roth TSP (if you expect similar or higher bracket), or a split for tax diversification.

Traditional TSP vs. Roth TSP

Unlike 401(k) plans at many employers, TSP has offered Roth contributions since 2012. The decision isn't binary — you can split contributions between traditional and Roth.

• Traditional TSP: contributions reduce current taxable income; withdrawals in retirement are fully taxed as ordinary income. Favored when you expect to be in a meaningfully lower tax bracket in retirement than today.
• Roth TSP: contributions are after-tax; qualified withdrawals in retirement are tax-free. Favored when you expect your bracket in retirement to be equal to or higher than today — or when tax diversification has value you can't predict.
• Most federal employees: a FERS annuity (fully taxable), Social Security (85% taxable above ~$44K combined income), and TSP RMDs can push retirees into the 22–24% bracket even without employment income. Pre-retirement income in a high-GS grade is often not dramatically different. Roth TSP makes sense for many, but run the numbers with your actual FERS annuity.

Roth TSP and RMDs: Under SECURE 2.0 § 325 (effective 2024), Roth 401(k) and Roth TSP balances are no longer subject to lifetime required minimum distributions — matching the longtime rule for Roth IRAs.² This makes Roth TSP more attractive for those who don't need to draw down immediately in retirement.

2026 Roth catch-up mandate: Starting January 1, 2026, if your prior-year wages exceeded $150,000, catch-up contributions must go to Roth, regardless of your current election. TSP will enforce this automatically.¹

TSP withdrawal strategies in retirement

TSP Modernization Act of 2017 (effective September 2019) significantly expanded withdrawal flexibility. You are no longer locked into a single partial withdrawal plus full withdrawal.³ Four options:

1. Monthly payments: set a fixed dollar amount or a life-expectancy-based amount. Amount can be changed at any time. Works well if TSP is your primary income source.
2. Partial withdrawals: take specific dollar amounts as needed, with no limit on frequency (subject to TSP processing timelines). Good for irregular needs — Roth conversions, large one-time expenses.
3. Single full withdrawal: take everything at once. Usually only makes sense if rolling to an IRA or if TSP has minimal balance.
4. Annuity purchase: TSP's MetLife annuity provider converts balance to a lifetime income stream. Generally not competitive vs. commercial annuities; rarely the optimal choice, but worth modeling if longevity risk is paramount.

Withdrawal sequencing with FERS annuity and Social Security

If your FERS annuity + FERS supplement already covers most living expenses before age 62, you may not need to draw on TSP immediately. Letting TSP compound during the early retirement years improves long-run outcomes. Once Social Security starts (and the FERS supplement stops at 62), revisit TSP withdrawal levels.

Staying in TSP vs. rolling to an IRA

This is the decision most federal employees get wrong. TSP has structural advantages over IRAs that most advisors don't discuss honestly (because they earn no revenue from assets left in TSP).

• TSP's advantages: expense ratios of 0.05% (vs. 0.10–1.0%+ in typical IRA mutual funds), G Fund access (no equivalent in IRA universe — government-rate return with no credit or duration risk), and simplified creditor protection under federal law.
• IRA's advantages: vastly broader investment options, in-plan Roth conversion capability (TSP does not allow in-plan Roth conversions), RMD aggregation across multiple IRAs (TSP requires its own RMD separately), and easier beneficiary designations for complex estates.
• Common middle path: leave traditional TSP in TSP through early retirement while making strategic Roth conversions by rolling portions to a traditional IRA first, then converting. This lets you use the G Fund for stability while managing tax brackets in retirement.

One rule: if you're doing a partial rollout, roll the traditional (pre-tax) balance first for conversion flexibility. Roth TSP can stay in TSP (or roll to Roth IRA) without tax impact — and Roth IRA has no RMDs, making it a good long-run holding place.

TSP and IRMAA: the withdrawal-size trap

Traditional TSP withdrawals count as ordinary income. At certain income thresholds, Medicare Part B and Part D premiums increase materially (IRMAA surcharges). For 2026, the first IRMAA tier for single filers begins at $109,000 MAGI.⁴

A large TSP distribution in a single year — say, rolling $300,000 traditional TSP to an IRA — will spike MAGI and trigger IRMAA surcharges two years later (IRMAA uses income from 2 years prior). If you're enrolled in Medicare or approaching 65, plan large TSP distributions with IRMAA lookback in mind. Spreading a rollout over 2–3 years can save thousands in Part B premiums.

RMDs from TSP

TSP is subject to RMDs like any pre-tax retirement account. Under SECURE 2.0:⁵

• If born 1951–1959: RMD age is 73.
• If born 1960 or later: RMD age is 75.
• Roth TSP: no lifetime RMDs (post-SECURE 2.0 § 325, effective 2024).

TSP calculates RMDs automatically using the Uniform Lifetime Table. Unlike IRA RMDs, TSP RMDs cannot be aggregated with IRA RMDs — each account type must satisfy its own RMD separately.

Sources

1. IRS — 401(k) limit increases to $24,500 for 2026; catch-up $8,000 (50+); super catch-up $11,250 (60–63); mandatory Roth catch-up rule for wages > $150,000.
2. TSP — SECURE 2.0 Act § 325: Roth TSP balances exempt from lifetime RMDs starting 2024.
3. TSP — Contribution Types and Withdrawal Options (post-Modernization Act, effective 2019).
4. CMS — 2026 IRMAA: first single-filer surcharge tier begins at $109,000 MAGI.
5. IRS — SECURE 2.0 RMD ages: 73 (born 1951–1959), 75 (born 1960+).

TSP contribution limits and tax values verified against IRS Rev. Proc. 2025-67 and CMS 2026 publications. Current as of April 2026.