acalculator

What is my TSP loan payment?

Type your own TSP contributions and earnings, the loan amount, the G Fund rate, the loan type, and the term. The TSP loan calculator shows the most you can borrow now, the processing fee, the payment taken from each paycheck, and the interest you pay back into your account.

Your numbers

An example rate, not today’s rate. tsp.gov shows the current one.
Loan type
Paychecks per year
Other TSP loans
Payment per paycheck
$171.93

You repay $171.93 per paycheck, 130 payments, with $2,351.53 of interest back into your account.

Most you can borrow now
$30,000.00
Processing fee
$50.00
Money you receive
$19,950.00
Total interest
$2,351.53
Total repaid
$22,351.53
Number of payments
130

Payment per paycheck: $171.93. You repay $171.93 per paycheck, 130 payments, with $2,351.53 of interest back into your account.

How fast is the loan paid back?

Every payment

The results are estimates for information only. They are not financial, tax, or legal advice. Check the numbers with your lender or a qualified professional before you decide. Terms of use

How to calculate

Computes the most you can borrow from your Thrift Savings Plan account, the processing fee, the payment per paycheck at the G Fund rate, the interest paid back into your account, and the schedule.

Example with the default inputs (Your contributions and earnings $60,000.00, Loan amount $20,000.00, G Fund rate 4.5%, Loan type General purpose, Repayment term (months) 60, Paychecks per year Every 2 weeks): You repay $171.93 per paycheck, 130 payments, with $2,351.53 of interest back into your account.

Method: Limit = min(your contributions and earnings, max(half of them plus loans owed, $10,000) − loans owed, $50,000 − highest loan balance in 12 months); payment = L·r ÷ (1 − (1 + r)^−n) with r = G Fund rate ÷ paychecks a year and n = months × paychecks a year ÷ 12, rounded.

  • The three TSP limits as tsp.gov states them; My Account shows the exact amount for you.
  • Level payments each paycheck with interest on the unpaid balance; the last payment clears the balance.
  • The number of payments is the term in months × paychecks a year ÷ 12, rounded to the nearest whole payment; the TSP sets the exact count.
  • The G Fund rate is the one you type; no live rates.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Your contributions and earnings $60,000.00, Loan amount $20,000.00, G Fund rate 4.5%, Loan type General purpose, Repayment term (months) 60, Paychecks per year Every 2 weeks gives Most you can borrow now $30,000.00, Payment per paycheck $171.93, Number of payments 130, Processing fee $50.00, Money you receive $19,950.00, Total interest $2,351.53.Source: Thrift Savings Plan, TSP loans (loan types and terms, $50 and $100 fees, $1,000 minimum, the three limits on the maximum, the G Fund rate for the month before you apply), https://www.tsp.gov/tsp-loans/ (retrieved 2026-10-05)
  2. Your contributions and earnings $15,000.00, Loan amount $8,000.00, G Fund rate 4%, Loan type General purpose, Repayment term (months) 24, Paychecks per year Monthly, TSP loans you owe now $2,000.00, Highest loan balance in the last 12 months $6,000.00 gives Most you can borrow now $8,000.00, Number of payments 24, Payment per paycheck $347.40, Total interest $337.59.Source: Thrift Savings Plan, TSP loans (loan types and terms, $50 and $100 fees, $1,000 minimum, the three limits on the maximum, the G Fund rate for the month before you apply), https://www.tsp.gov/tsp-loans/ (retrieved 2026-10-05)
  3. Your contributions and earnings $200,000.00, Loan amount $50,000.00, G Fund rate 4.875%, Loan type Primary residence, Repayment term (months) 180, Paychecks per year Every 2 weeks, TSP loans you owe now $0.00, Highest loan balance in the last 12 months $0.00 gives Most you can borrow now $50,000.00, Number of payments 390, Processing fee $100.00, Payment per paycheck $180.86, Total interest $20,534.50.Source: Thrift Savings Plan, TSP loans (loan types and terms, $50 and $100 fees, $1,000 minimum, the three limits on the maximum, the G Fund rate for the month before you apply), https://www.tsp.gov/tsp-loans/ (retrieved 2026-10-05)
  4. Your contributions and earnings $30,000.00, Loan amount $5,000.00, G Fund rate 0%, Loan type General purpose, Repayment term (months) 13, Paychecks per year Every 2 weeks gives Number of payments 28, Payment per paycheck $178.57, Total interest $0.00.

How it works

With C your own contributions and earnings (not counting agency contributions, the mutual fund window, or loans you owe), B the TSP loan balance you owe now, and H the highest loan balance in the last 12 months (taken as at least B):

  • Most you can borrow now = min(C, max((C + B) ÷ 2, $10,000) − B, $50,000 − H), never below 0, in exact decimals.
  • Processing fee = $50 for a general purpose loan, $100 for a primary residence loan. Money you receive = loan amount − fee.
  • Number of payments n = months × paychecks a year ÷ 12, rounded to the nearest whole payment (a half rounds up), in exact decimals. 60 months every 2 weeks is 130 payments.
  • Rate per payment r = G Fund rate ÷ paychecks a year. Payment per paycheck = L × r ÷ (1 − (1 + r)^−n), or L ÷ n at 0%.
  • Each paycheck, interest = balance × r and the rest of the payment lowers the balance; the last payment clears the balance. Nothing is rounded between payments. Total interest is the sum of the interest; total repaid = L + total interest.

Rules

  • You need at least $1,000 of your own contributions and earnings; the loan is $1,000 to $50,000 and no more than the limit.
  • A general purpose loan runs 12 to 60 months; a primary residence loan 61 to 180 months. Other inputs give no answer, with a message.
  • Paychecks a year: 26 (every 2 weeks), 24 (twice a month) or 12. The G Fund rate is 0% to 20%.

Worked examples by hand

The default: $60,000 of your own money, $20,000 general loan, 4.5%, 60 months, every 2 weeks. Limit = min(60,000, max(30,000, 10,000) − 0, 50,000) = $30,000. n = 60 × 26 ÷ 12 = 130; r = 0.045 ÷ 26. Payment = $171.93; interest $2,351.53; you receive 20,000 − 50 = $19,950.

A loan owed now: $15,000 of your own money, $2,000 owed, $6,000 highest in 12 months. Limit = min(15,000, max(8,500, 10,000) − 2,000, 50,000 − 6,000) = $8,000. Borrowing $8,000 at 4% monthly over 24 months: $347.40 a month.

A primary residence loan: $50,000 at 4.875% over 180 months, every 2 weeks. n = 390; payment $180.86; interest $20,534.50; fee $100.

13 months every 2 weeks at 0%. 13 × 26 ÷ 12 = 28.17, so 28 payments of 5,000 ÷ 28 = $178.57.

Other questions people ask

How much can I borrow from my TSP?

The smallest of three limits: your own contributions and earnings; the greater of half of them (plus any loan you owe) or $10,000, minus the loan you owe; and $50,000 minus your highest loan balance in the last 12 months. The minimum loan is $1,000.

What interest rate does a TSP loan charge?

The G Fund rate for the month before you request the loan. It stays the same for the life of the loan. Type the rate from tsp.gov; the calculator uses no live rates.

How long can I take to repay a TSP loan?

A general purpose loan is repaid in 12 to 60 months. A primary residence loan, for buying or building your main home, is repaid in 61 to 180 months.

Is there a fee for a TSP loan?

Yes, a one-time processing fee that comes out of the loan: $50 for a general purpose loan and $100 for a primary residence loan. A $20,000 general loan pays you $19,950.

Where does the interest go?

Back into your own TSP account, with the principal. The cost of the loan is the growth the borrowed money would have earned while it was out of the funds.

How is the payment per paycheck worked out?

As a level payment: L × r ÷ (1 − (1 + r)^−n), with r the G Fund rate ÷ paychecks a year and n the number of paychecks. $20,000 at 4.5% over 130 biweekly paychecks is $171.93.