TSP Withdrawal Calculator

For federal employees, postal workers and service members. Enter your TSP balance and the monthly installment you plan to take; the calculator shows how long it lasts and the safe amount for 30 years.

TSP in the FERS three-legged stool

The FERS pension and Social Security (or the FERS supplement before 62) cover a large share of most federal retirees' needs, so the TSP's job is the remaining gap — typically $1,000–3,000 a month. Enter that gap, not your full budget. Because TSP funds are among the cheapest in existence (expense ratios around 0.05%), a 5% return assumption is reasonable for a mix of C, S, I and F funds; use 3–4% if you are mostly in the G Fund.

How the calculator works

Each month the balance earns one month of return, then the withdrawal is taken out. Every 12 months the withdrawal is increased by the inflation rate so your spending power stays level. If you enter a tax rate, each withdrawal is grossed up so the after-tax amount you keep matches the number you typed. The calculator stops when the balance hits zero, or after 100 years if it never does.

The "to last 20 / 25 / 30 years" figures are solved by bisection: the largest starting withdrawal that still survives that horizon under the same return and inflation assumptions.

TSP withdrawal options

• Installment payments — fixed dollar amount monthly, quarterly or annually, changeable at any time; or life-expectancy-based amounts. This calculator models the fixed-dollar option with an inflation increase you set.
• Partial withdrawals — unlimited single withdrawals of $1,000 or more, once every 30 days.
• Annuity purchase — convert some or all to a MetLife life annuity. Irreversible; compare the monthly payout to the "to last 30 years" box above before committing.
• Age 55 rule — penalty-free if you separate in or after the year you turn 55 (age 50, or 25 years of service, for public-safety employees).
• RMDs — apply from age 73; Roth TSP balances are exempt from lifetime RMDs from 2024.
• Tax withholding — the TSP withholds 20% federal on most withdrawals unless you elect otherwise for installments over 10 years.

Choosing realistic inputs

• Annual return. 4–5% is a conservative planning number for a balanced portfolio; 6–7% is closer to long-run history for 60/40; cash and CDs are 3–5% today but fall when rates fall.
• Inflation. The Federal Reserve targets 2%; the 30-year U.S. average is about 2.5%. Healthcare inflation runs higher, so retirees with large medical costs should test 3–3.5%.
• Withdrawal. Use what you actually spend, minus guaranteed income (Social Security, pension, annuity). That net gap is what savings must cover.

G Fund safety vs. running out

Many retirees move everything to the G Fund at retirement for safety. It cannot lose money, but at roughly 4% it barely beats inflation, so a 4% withdrawal means spending principal from day one. The default run above at 5% shows the balance lasting decades; rerun it at 3.5% and watch the horizon shrink. Holding 1–3 years of withdrawals in G and the rest in the L Income or a C/S/I mix is the usual compromise.

SavingsLast calculators are educational estimates. They assume a constant average return and steady inflation; real markets are volatile and sequence-of-returns risk can shorten how long money lasts. Nothing here is financial, investment, tax, or legal advice. Consult a qualified professional before making decisions.