How much does a TSP annuity pay per $100,000?

It depends almost entirely on your age and the interest rate index in force on the purchase date. At the October 2026 index of 5.2 percent, TSP's own calculator quotes about $714 a month for a 65 year old buying a single life annuity with level payments and no extra features. The same $100,000 pays roughly $605 at 55 and about $1,174 at 80. Adding a survivor benefit or a beneficiary feature lowers all of those.

What is the TSP annuity interest rate index?

It is the single number TSP publishes each month that sets annuity prices, and it moves. TSP lists it at 5.2 percent for October 2026, up from 4.575 percent in January 2026. A higher index means a higher monthly payment for the same money, so timing matters. TSPFS24 warns that if you request an annuity near the end of a month, the purchase may fall into the next month and use that month's index instead.

Do TSP annuity payments keep up with inflation?

No. The increasing-payment option rises a flat 2 percent on each anniversary of the first payment. That is a fixed 2 percent, not a cost of living adjustment and not tied to CPI. It is worth checking against your own expectations: the payment starts noticeably lower than a level annuity, and at 65 it takes roughly 11 years of 2 percent rises before the increasing option catches the level one in dollar terms.

What does the 100 percent survivor option cost?

Roughly 12 percent of the monthly payment compared with the 50 percent option, at typical retirement ages. For a 65 year old with a 62 year old spouse, TSP quotes about $614 a month at 100 percent survivor against about $695 at 50 percent on a $100,000 purchase. The 100 percent option keeps the payment whole for whoever survives. The 50 percent option halves it for the survivor, whichever of you that turns out to be.

What is the difference between cash refund and ten-year certain?

Cash refund pays your beneficiary a lump sum equal to whatever is left of the purchase price if you die before the payments add up to it. Ten-year certain keeps the monthly payments going to your beneficiary for the rest of a ten year period if you die inside it. Both reduce your own payment. For most buyers ten-year certain costs less, because its guarantee ends at ten years. That flips late in life: at the 5.2 percent index, cash refund pays more than ten-year certain from age 82 on level payments and from 83 on increasing ones, because a buyer that old is less likely to outlive the ten years. TSPFS24 states ten-year certain cannot be combined with a joint life annuity.

Are TSP annuity payments subject to the 10 percent early withdrawal penalty?

No, and TSPFS24 is explicit: your annuity payments are not subject to the IRS early withdrawal penalty, regardless of your age. That makes an annuity one of the few ways to get TSP money moving before 59 and a half with no penalty exposure. Payments bought with traditional money are still taxed as ordinary income in the year you receive them.

Can I change my mind after buying a TSP annuity?

No. TSPFS24 states that once the funds have been disbursed to the annuity provider you cannot cancel the annuity, change the option, or change the joint annuitant. You can change your beneficiary with the provider afterwards, and that is all. The money also stops being yours to manage, which is the real trade: you swap control and any upside for a payment that cannot run out.

Where do these numbers come from?

From TSP itself. TSP publishes the complete vendor factor table its own annuity calculator uses at https://www.tsp.gov/data/annuity_calculator/data.json (61,404 rows, of which 55,860 carry a price; read 2026-10-03), along with the arithmetic it applies to them: monthly = amount x ANN_FCTR x (1 + (index - 5) x INT_ADJ_FCTR) / 1,000. This calculator looks up the same row TSP would and runs the same formula, so the figure is not an approximation of TSP's price, it is TSP's price at the index you enter. TSP's own calculator is still the binding quote at purchase, because the index that applies is the one in force on the day the annuity is actually bought.

Calculator

TSP Life Annuity

What would your TSP balance actually pay as a lifetime monthly check? This estimates the payment under every option TSP offers, priced at the October 2026 annuity interest rate index of 5.2 percent, so you can see what each survivor benefit and beneficiary feature costs before you give up control of the money for good.

Reviewed by Jonathan D., 20-year federal employee · Formulas verified against TSP.gov · Updated October 2026

Rule snapshot

Reviewed October 3, 2026 · Sources: TSP: Annuities (TSPFS24), TSP annuity interest rate index, October 2026, TSP published annuity factor table (61,404 rows), TSP annuity interest rate index feed (CSV), TSP annuity calculator (the binding quote at purchase) · Inputs stay in your browser. Nothing you type is sent to a server or saved.

What you are buying with

Amount from your TSPMinimum $3,500, applied separately to your traditional and Roth balances.

Your age at purchaseWhole years. TSPFS24 says months are not considered in the annuity calculation.

Interest rate index (%)Prefilled with 5.2%, the published index for October 2026. TSP changes it monthly, and the rate in force on your purchase date is the one that counts. Accepts 1.2 to 20; the lowest TSP has published is 1.209% (July 2020).

The annuity option

Whose life it covers

Payment patternIncreasing starts lower and rises a flat 2% a year, not with inflation.

Extra featureEither feature lowers your monthly payment in exchange for paying a beneficiary.

What this models, and what it does not

Read the second list before you act on the number.

What this models

The published TSP annuity interest rate index, 5.2 percent for October 2026, editable so you can model another month from 1.2 to 20 percent (the lowest TSP has published is 1.209 percent, July 2020; below about 0.9 percent TSP’s linear adjustment would price some options at a negative payment, so the calculator refuses an index under 1.2)
Single life, joint life with a spouse, and joint life with a non-spouse survivor
Level payments and increasing payments, which rise a flat 2 percent each anniversary
The cash refund and ten-year certain features, at TSP’s own published factor for each
The 100 percent and 50 percent survivor options, with the resulting survivor payment shown
Every combination TSP refuses, with the reason quoted from TSPFS24
The $3,500 minimum purchase, flagged rather than silently ignored
A side by side table of every legal option, so the cost of each choice is visible
Break even in months and years, and what you give up against plain single life level

Not modeled

A binding quote. The payment uses TSP’s own published factors and formula, so it matches what TSP quotes at the same index — but the index that applies is the one in force on the day the annuity is actually purchased, and only TSP can commit to a price
Any combination TSP does not publish a factor for. Rather than interpolating, the calculator refuses and says so. The published table covers participant ages 25 to 94 and joint annuitant ages 1 to 99, and TSP’s own calculator will not quote a participant over 85, so neither does this one
Future revisions to the factor table. The factors here were read on 2026-10-03; TSP can change them, and a change would not appear here until the table is rebuilt
The tax on the payments. Traditional money is taxed as ordinary income when received. Use the TSP Withdrawal Tax Calculator for that
Combat zone tax-exempt contributions, which the annuity vendor spreads across your payments under a separate IRS calculation
Spousal rights paperwork. A married FERS or uniformed services participant needs a spousal waiver for any option other than joint life with spouse, level, 50 percent survivor
Any comparison against commercial annuities. TSP charges no commission, which commercial quotes usually do not match

The interest rate index is the part people miss

An annuity price has two moving parts: how long you are expected to live, and the interest rate TSP uses to discount the payments. The second one changes every month and it changes a lot. TSP held the index at 4.575 percent from January through April 2026, then moved it five times, reaching 5.2 percent for October 2026. On a $300,000 purchase at 65, that swing is worth roughly $120 a month for life: TSP's own factors put the single life level payment at $2,019.22 a month at 4.575 percent against $2,141.41 at 5.2 percent, a difference of $122.19.

TSPFS24 adds a timing warning worth reading twice. If you request an annuity late in a month, the purchase may not complete until the following month, and the provider uses the index in force when the annuity is actually purchased. The rate you saw when you filed the paperwork is not necessarily the rate you get.

TSP annuity interest rate index by month in 2026
Month	Interest rate index
October 2026	5.200%
September 2026	5.075%
August 2026	4.950%
July 2026	4.950%
June 2026	4.825%
May 2026	4.700%
January to April 2026	4.575%

Source: TSP historical annuity interest rate index, read 2026-10-03. TSP publishes a new figure every month.

Which combinations TSP actually sells

The option set is narrower than it looks. Three limits catch people out: a non-spouse joint annuitant gets level payments only, the ten-year certain feature cannot be attached to a joint life annuity, and a non-spouse survivor more than 10 years younger than you must take the 50 percent benefit unless they are a former spouse owed part of your account under a retirement benefits court order. This calculator does not quote that exception.

TSP life annuity options and which features each one allows
Annuity	Payment pattern	Survivor benefit	Extra features
Single life	Level or increasing	Not applicable	None, cash refund, or ten-year certain
Joint life with spouse	Level or increasing	100% or 50%	None or cash refund
Joint life with other survivor	Level only	100% only if not more than 10 years younger, otherwise 50%	None or cash refund

Source: TSPFS24, Annuities, pages 2 and 3. Note that TSPBK06, the old withdrawal booklet, is retired. The live publications are TSPFS24 for annuities and TSPBK25 for distributions.

Where these numbers come from

TSP publishes the vendor factor table its own annuity calculator runs on. It sits at tsp.gov/data/annuity_calculator/data.json, it holds 61,404 rows, and 55,860 of them carry a price. Each row gives two numbers for one combination of participant age, joint annuitant age, payment pattern, feature and survivor percentage: an annuity factor, and an interest adjustment factor that moves it away from a 5 percent reference index. TSP publishes the arithmetic too, in the script on its own calculator page: monthly = amount x ANN_FCTR x (1 + (index - 5) x INT_ADJ_FCTR) / 1,000.

So this calculator does not model anything. It reads the row TSP would read and runs the formula TSP runs. All 55,860 priced combinations are checked against that formula in the test suite, to the cent, with no tolerance. Where TSP publishes no factor the calculator refuses to quote rather than filling the gap with a guess: the table covers participant ages 25 through 94 and joint annuitant ages 1 through 99, and TSP's own calculator will not quote a participant over 85.

An earlier version of this page said TSP kept its factors private, and that this tool was a mortality model calibrated against TSP's calculator and accurate to 0.38 percent on average. The premise was wrong. The factors were public the whole time, and the model was off by far more than that on joint annuities with the cash refund feature and on joint annuitants under 25. The model and the accuracy claim are both gone.

What is still worth confirming on TSP's own annuity calculator for the authoritative figure. If you are weighing the annuity against simply drawing the money down, the withdrawal tax calculator and the RMD calculator show the other side of that decision.