TSP G Fund Explained: The Feature No IRA Can Match

The G Fund is the single most unusual investment available to federal employees — and the most commonly misunderstood. It earns yields similar to intermediate-term U.S. Treasuries with zero principal risk. That combination does not exist anywhere in the retail investment marketplace. Here's how it actually works, what it's paying in 2026, and when it should (and shouldn't) anchor your TSP strategy.

What the G Fund actually is

The G Fund — Government Securities Investment Fund — invests exclusively in a special series of U.S. Treasury securities issued directly to the Thrift Savings Plan and not available for purchase by the general public.¹

This is not a Treasury money market fund. It is not a short-term T-bill fund. It is not a stable-value fund backed by insurance contracts. It is a direct obligation of the U.S. federal government, held entirely within the TSP structure.

The interest rate is recalculated monthly by the U.S. Treasury as the weighted average yield of approximately 202 marketable U.S. Treasury securities with 4 or more years to maturity. Practically speaking, the G Fund's rate tracks somewhere between the 5-year and 10-year Treasury yield — intermediate-term yields — reset monthly.

What the G Fund pays in 2026

As of April 2026, the G Fund returned 0.36% for the month — an annualized rate of approximately 4.3%.² Year-to-date through April 2026, the G Fund returned 1.41%.

Monthly rates since early 2026 have ranged from approximately 0.34% to 0.36%, reflecting intermediate-term Treasury yields in the current rate environment. The exact rate resets on the first business day of each month and is published at tsp.gov/funds-individual/g-fund/.

For current rates, check the TSP website directly — these numbers change every month.

The G Fund vs. everything you can buy in an IRA

When federal employees roll TSP to an IRA, one of the first questions is: "Can I recreate the G Fund?" The answer is: not really. Here's the honest comparison:

The G Fund sits in a category of its own: intermediate-term yield, zero price volatility, and no counterparty risk beyond the U.S. government itself. Money market funds in an IRA can match it on yield right now — but they track short-term rates, which fall when the Fed cuts rates. The G Fund tracks longer-term rates, which are more stable and structurally higher than short-term rates in most interest rate environments.

Stable-value funds are the closest structural analog, but they're only available inside employer-sponsored plans (401k, 403b) — not IRAs. When you roll TSP to an IRA, stable-value disappears as an option entirely.

How the G Fund fits into the L Funds

If you use one of the TSP Lifecycle (L) funds, you already have a G Fund allocation — you just may not have noticed it:

• L Income (already in withdrawal phase): ~29% G Fund
• L 2025 (retired/redeeming): G Fund is the primary holding
• L 2030: ~25% G Fund
• L 2035: ~20% G Fund
• L 2040: ~17% G Fund
• L 2045: ~14% G Fund
• L 2050: ~12% G Fund
• L 2055, 2060, 2065: ~6–8% G Fund

L Funds automatically increase G Fund allocation as your target date approaches. This is the automated conservative shift — the G Fund serves as the low-volatility anchor of the Lifecycle design.

The right G Fund allocation by career stage

Early career (25–45): minimize G Fund

A federal employee 20+ years from retirement who holds 30–40% in the G Fund is almost certainly leaving money on the table. The G Fund's 4% return is roughly in line with inflation's long-run drain on purchasing power — it preserves capital in nominal terms but grows wealth slowly in real terms.

Early-career federal employees with a long runway are better served by maximizing the C, S, and I fund allocations. The G Fund's principal protection has zero value when you won't touch the money for two decades. Volatility is the price of growth, and early career employees have time to absorb it.

Common mistake: New federal employees defaulting to the L Income or a conservative blend because "safety" sounds right. A 28-year-old in L Income is holding ~29% in G Fund — the allocation appropriate for someone drawing down, not accumulating.

Mid-career (45–55): gradual shift toward 15–25% G Fund

As retirement approaches, the G Fund starts earning its place. A reasonable allocation for a federal employee 10–15 years from retirement includes 15–25% in G Fund as a ballast — reducing portfolio volatility during market downturns without anchoring long-term growth. This is roughly what the L 2035–2040 funds do automatically if you pick the right target-date fund for your situation.

Near-retirement (55–62): G Fund as an income floor

In the final years before separation, a deliberate G Fund strategy can significantly reduce sequence-of-returns risk — the danger that a market drop in the first few years of retirement forces you to sell equities at depressed prices to cover expenses.

A practical structure:

• Hold 2–3 years of expected TSP withdrawals in the G Fund
• Keep the remainder in C, S, and I funds for long-term growth
• In a market downturn, draw from the G Fund first while equities recover
• Refill the G Fund "bucket" from equity gains in good years

This is the two-bucket strategy applied to TSP. It's simple to execute with only the G, C, and S funds — and it means you never have to sell equities at a loss to pay living expenses.

In retirement (62+): the G Fund as the safe "floor"

Once Social Security starts and your FERS pension + SS covers most or all of your spending, the pressure on TSP withdrawals decreases. At that point, the G Fund's primary role shifts from income buffer to estate / volatility management.

Some federal retirees with a large TSP and modest spending needs hold 30–50% in G Fund in retirement — not because they need the income, but because they have more capital than they need and prefer lower volatility for what's effectively legacy money. That's a legitimate choice. The G Fund earns a real return and pays monthly interest without requiring any equity market exposure.

The G Fund's real risk: inflation erosion

The G Fund has no principal risk, but it has purchasing-power risk. At 4.1–4.3% per year in 2026, it is roughly keeping pace with current inflation — but over a 30-year retirement horizon, that's a fragile balance. In 2012–2021, the G Fund paid 1.4–2.5% annually while inflation ran 2–4%. Real returns were effectively zero or negative during that period.

A federal employee who retires at 57 with 100% of their $1.2M TSP in the G Fund and lives to 87 will have:

• Preserved nominal capital through 2026's rate environment
• Possibly lost significant real purchasing power if inflation outpaces G Fund rates
• Significantly underperformed a mixed equity/bond portfolio over that 30-year horizon

The G Fund is a tool, not a total strategy. Its principal protection is most valuable when you need it — in the years around retirement when sequence-of-returns risk is highest, and as a stable allocation within a balanced portfolio. Over the full arc of a 25–30-year retirement, a significant equity allocation is still necessary to keep pace with inflation and avoid running out of money.

Should the G Fund keep you from rolling to an IRA?

The G Fund is the most commonly cited reason to stay in TSP after separation. It's a legitimate reason. But it shouldn't be the only factor in a stay-vs-rollover decision.

Here's when the G Fund argument is strongest:

• You're retiring before 59½ and need the G Fund as the stable piece of your bucket strategy while you use Rule of 55 withdrawals from TSP
• Interest rates are elevated (2024–2026 environment) and the G Fund is earning a real yield vs. alternative options
• You don't have a specific IRA strategy that requires the assets to move — staying in TSP and using the G Fund is simpler and cheaper

Here's when rolling to an IRA may be worth giving up the G Fund:

• You're working with a fee-only advisor who actively manages a single consolidated portfolio, and splitting TSP from IRA creates coordination friction worth more than the G Fund advantage
• You have estate planning needs (trust beneficiaries, generation-skipping planning) that IRA structures handle better than TSP's beneficiary rules
• Interest rates fall significantly and the G Fund yields 1–2% — the advantage collapses

The partial rollover resolves this dilemma for most people: keep a meaningful G Fund allocation in TSP (typically two to three years of expected withdrawals, minimum) while rolling the growth portion to an IRA. You preserve the safe bucket without forfeiting all the IRA's flexibility.

For more detail, see: TSP Stay vs. Rollover: The Complete Decision Guide.

G Fund common mistakes

1. Over-allocating in accumulation: Holding 30–50% G Fund at age 35–45 drags long-run returns without any benefit — volatility is your friend when you have 20+ years of compound growth ahead.
2. Under-allocating near retirement: Heading into retirement with 100% in C/S without a stable bucket creates real sequence-of-returns risk in year one of a market correction.
3. Treating the G Fund as "safe" for the long haul: Safe from price volatility, yes. Not safe from purchasing power erosion over a 30-year retirement.
4. Leaving the G Fund when moving to an L Fund: If you manually moved to 100% C Fund and then switch to an L Fund, you're not "adding" G Fund — you're changing your allocation entirely. Understand what you're buying before you click.
5. Rolling everything to an IRA without modeling the G Fund loss: The G Fund yield vs. money market differential may be $3,000–$8,000/year on a $200,000 stable allocation. Over 20 years, that's real money. Model it before you roll.

1. TSP G Fund — tsp.gov. G Fund description, rate calculation methodology, and current monthly returns. Rates verified May 2026.
2. TSP Fund Information May 2026 — tsp.gov. Monthly return data for all TSP funds including G Fund monthly figures.
3. What to Know About the TSP G Fund — Morningstar. Independent analysis of G Fund mechanics and comparison to IRA equivalents.
4. TSP vs. Fidelity and Vanguard: A $1M Retirement Case Study — FedSmith. Fee and return comparison between TSP funds and IRA equivalents, including G Fund analysis.
5. The G Fund's Silent Erosion — Federal News Network. Analysis of G Fund inflation risk and purchasing-power concerns over long retirement horizons.

Values verified as of May 2026. G Fund rates change monthly; check tsp.gov for current figures.