Book a free benefits review
A wooden desk from above with a vintage printing calculator, a pencil and graph paper under a brass lamp

TSP loan

TSP loan calculator

This TSP loan calculator estimates the payment per pay period on a TSP loan, 26 payments a year at the G Fund rate you type, and the total interest, which goes back into your own account. It adds the $50 or $100 processing fee and checks your amount against the $1,000 minimum and the main loan limits.

The calculator

What the calculator shows

  • Your estimated payment per pay period, on 26 pay periods a year.
  • The number of payments over the term you pick.
  • Total repaid and total interest, both credited to your own account.
  • The processing fee, $50 for a general purpose loan or $100 for a residential loan.
  • An estimated maximum loan, with a flag if your amount is over it or under the $1,000 minimum.

Your inputs

Prefilled with an example so the result is never empty. Change any number; the result updates as you type.

Educational estimate on the assumptions you entered

$173.50 a pay period

130 payments over 5 years

Want this run on your own records? A Federal Retirement Consultant (FRC®) checks the inputs with you, free.

Get matched with an FRC
Total repaid
$22,555, back into your own account
Interest, paid to yourself
$2,555
Processing fee
$50
Your estimated maximum
$50,000: the smallest of $50,000, your vested balance, and the greater of half that balance or $10,000; the 12-month lookback and your own-contributions limit can lower it
Checks
Within the estimated limits on these inputs

Assumptions behind this estimate

  • The rate is what you type. The TSP sets it from the G Fund rate on the 15th of the month before your request.
  • 26 equal payments a year. Your loan agreement sets the actual schedule, and the TSP re-amortizes if your pay cycle changes (5 CFR 1655.16, retrieved 2026-10-13).
  • No loan is outstanding and none was in the last 12 months. If one was, the limits are lower than shown.
  • Your own-contributions limit is not checked. Agency contributions cannot be borrowed; compare your amount with the employee portion on your statement.
  • Payments stay on schedule. Missed payments, separation or nonpay status change the outcome and can make the balance taxable.
  • Lost fund returns are not modeled. The calculator shows the interest you pay yourself, not what the money would have earned in the funds.

Educational estimate on the assumptions you entered, not a projection or a promise and not OPM's official computation. FFEBA is an education organization, not a financial advisor, and does not give personalized financial, tax or legal advice.

Inputs you will enter

  • Loan amountWhat you want to borrow, at least $1,000 (5 CFR 1655.6, retrieved 2026-10-13). The fee comes out of the proceeds, so the check is the amount less the fee.
  • Loan typeGeneral purpose, up to 5 years, for any reason; or primary residence, up to 15 years, for buying or building the home you live in, with a signed contract as proof (5 CFR 1655.20, retrieved 2026-10-13).
  • Term in yearsHow long you repay. A general purpose loan runs at least 1 year; a residential loan runs at least 61 months, so pick 6 years or more for that type (5 CFR 1655.5, retrieved 2026-10-13). The calculator limits the term to 5 or 15 years by type.
  • Interest rate (the G Fund rate when you apply)The G Fund rate in effect on the 15th of the month before you request the loan (5 CFR 1655.7, retrieved 2026-10-13). Look it up on tsp.gov before you type it; the rate is fixed once the loan is made.
  • Your vested TSP balanceYour balance minus any agency automatic 1 percent contributions you have not yet vested in. Your quarterly statement shows it.

How we compute it

The payment is a standard amortized loan payment: the amount times the per-period rate, divided by 1 minus (1 + the per-period rate) raised to the negative number of payments. The per-period rate is the yearly rate divided by 26, and the number of payments is the term times 26. Total repaid is the payment times the number of payments, and interest is total repaid minus the amount borrowed. Payments come out of your pay by payroll deduction, and both principal and interest are credited back to your account in your current contribution allocation (5 CFR 1655.9 and 1655.14, retrieved 2026-10-13).

The TSP caps a loan at the smallest of three limits: your own contributions and their earnings; 50 percent of your vested balance or $10,000, whichever is greater, minus any loan balance you already owe; and $50,000 minus your highest outstanding loan balance during the last 12 months (5 CFR 1655.6, retrieved 2026-10-13). The calculator checks the second and third limits on your vested balance with no loan outstanding. It cannot see your own-contributions total, so check that on your statement.

Missed payments matter. If you miss two or more payments and do not catch up within the cure period, or the loan is not repaid by its maximum term, the unpaid balance is declared a taxable distribution (5 CFR 1655.15, retrieved 2026-10-13). There is also a cost the payment does not show: the money you borrow is taken out of your funds and stops earning their returns while it is out; it earns only the interest you pay yourself (5 CFR 1655.9, retrieved 2026-10-13).

$1,000Minimum TSP loan5 CFR 1655.6, retrieved 2026-10-13
$50,000Top of the loan limit, less your highest balance in 12 months5 CFR 1655.6, retrieved 2026-10-13
$50 / $100Fee for a general purpose / residential loan5 CFR 1655.21, retrieved 2026-10-13
2 loansMost you can have at once, only one residential5 CFR 1655.4, retrieved 2026-10-13

A worked example

An employee with a $60,000 vested balance and no loan borrows $20,000 for general purposes over 5 years at an assumed G Fund rate of 4.25 percent. The per-period rate is 4.25% / 26, about 0.1635 percent, over 5 x 26 = 130 payments. The payment works out to about $170.90 a pay period, so about $22,216 is repaid in all, of which about $2,216 is interest credited back to the account. The $50 fee comes off the proceeds, so the check is $19,950.

The estimated maximum on these inputs is the smaller of $50,000 and 50 percent of $60,000, which is $30,000, so the $20,000 request fits, provided the employee's own contributions and earnings are at least $20,000. This is an educational estimate on the assumptions shown.

What to do with your estimate

Read how TSP loans work before you apply, then use the TSP calculator to see what the borrowed money might have done at a return you choose. If you are near separation, the TSP withdrawal calculator shows how a smaller balance changes your drawdown. More calculators are on the tools page.

FFEBA is an education organization. If you want someone to look at your own numbers, we can match you with a Federal Retirement Consultant (FRC), a professional trained on federal benefits. The FRC designation is listed with FINRA. The first review is free, nothing is booked until you choose a time, and you are never obligated to work with anyone we introduce. Get matched with an FRC.

Questions about this calculator

How much can I borrow from my TSP?

At least $1,000, and no more than the smallest of three limits: your own contributions and their earnings; 50 percent of your vested balance or $10,000, whichever is greater, minus any loan you already owe; and $50,000 minus your highest outstanding loan balance in the last 12 months (5 CFR 1655.6, retrieved 2026-10-13).

What interest rate does a TSP loan charge?

The G Fund rate in effect on the 15th of the month before your loan request, fixed for the life of the loan (5 CFR 1655.7, retrieved 2026-10-13). The interest is credited to your own account along with the principal (5 CFR 1655.9, retrieved 2026-10-13).

How long can a TSP loan run?

A general purpose loan runs 12 to 60 months. A residential loan, for buying or building a primary residence, runs 61 to 180 months and needs a signed purchase contract or builder's agreement (5 CFR 1655.5 and 1655.20, retrieved 2026-10-13). You can pay either off early without a penalty (5 CFR 1655.17, retrieved 2026-10-13).

How many TSP loans can I have at once?

Two, and no more than one of them can be a residential loan. After you repay a loan in full, more than 30 business days must pass before you can take another (5 CFR 1655.2 and 1655.4, retrieved 2026-10-13).

What happens to a TSP loan if I leave federal service?

Payroll deductions stop. The TSP sends a notice, and if you do not begin repaying or pay the loan off within the period it sets, the unpaid balance is treated as a loan offset, a taxable distribution (5 CFR 1655.15, retrieved 2026-10-13). If you are under 59 1/2 and no exception applies, the IRS 10 percent additional tax can apply as well (IRS, retrieved 2026-10-13).

Is this the payment the TSP will set?

No. This is an educational estimate on the amount, term and rate you type. The TSP sets the actual payment in your loan agreement and the rate on the date of your request.

Reviewed by the FFEBA education team. Last reviewed October 2026.

Sources

  1. Electronic Code of Federal Regulations, 5 CFR part 1655 (TSP loan program), retrieved 2026-10-13
  2. Internal Revenue Service, Topic no. 558, additional tax on early distributions from retirement plans, retrieved 2026-10-13

Every government figure on this page carries its source and retrieval date. Worked examples are educational estimates on the assumptions shown, not a projection of any person's benefit. FFEBA is an education organization, not a financial advisor.

Keep reading

Read the rule behind the math.