# TSP Withdrawal Calculator > For federal employees and military: model TSP installments, tax, growth and inflation to see how long your Thrift Savings Plan lasts. Source: https://savingslast.com/tsp-withdrawal-calculator/ Markdown: https://savingslast.com/tsp-withdrawal-calculator.md Site: SavingsLast, free retirement drawdown calculators. Educational estimates, not advice. 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. *Interactive calculator on the page: https://savingslast.com/tsp-withdrawal-calculator/. The same engine is the MCP tool how_long_will_money_last at https://savingslast.com/mcp.* ## 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 your full budget and put the FERS pension and Social Security in their own boxes. Or leave those boxes at 0 and enter only the gap. 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. The withdrawal itself rises a little every month, at the rate that compounds to your inflation figure over a full year, 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.** Enter what you actually spend. Put Social Security and any pension in their own boxes, and the calculator takes them off your spending. Social Security counts from the starting age you enter. With those boxes at 0, enter only the gap that 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. ## Frequently asked questions **How long will $500,000 in TSP last?** Taking $2,000 a month after 15% tax at 5% return and 2.5% inflation, about 23 years. At $3,000 a month it drops to about 14 years. **Can I withdraw from TSP at 57 without penalty?** Yes, if you separated from federal service in or after the year you turned 55 — the minimum retirement age for most FERS employees is 57, so this applies to a typical immediate retirement. **Are TSP withdrawals taxed?** Traditional TSP withdrawals are federal ordinary income; most states tax them too, though several exempt some federal retirement income. Roth TSP qualified withdrawals are tax-free. **Should I take TSP installments or buy the annuity?** Installments keep control and legacy value; the annuity removes longevity risk but locks in today’s rates permanently. Compare the annuity quote to the 30-year sustainable amount above; if the annuity is not meaningfully higher, installments usually win. ## Related calculators - [Retirement drawdown calculator](https://savingslast.com/retirement-drawdown-calculator/) - [Savings withdrawal calculator](https://savingslast.com/savings-withdrawal-calculator/) - [401(k) distribution calculator](https://savingslast.com/401k-distribution-calculator/) - [IRA withdrawal calculator](https://savingslast.com/ira-withdrawal-calculator/) - [403(b) withdrawal calculator](https://savingslast.com/403b-calculator/) - [457(b) withdrawal calculator](https://savingslast.com/457b-calculator/) 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.