About the Pension Lump Sum vs Annuity Calculator
This calculator helps you decide between taking a pension as a one-time lump sum or as a monthly annuity for life. Enter the lump sum offered, the monthly pension, when payments start, your life expectancy, any cost-of-living increase, and the return you think you could earn investing the lump sum yourself.
It reports three numbers that matter: the present value of the pension payments at your expected return (what the monthly checks are “worth” in today’s money), the implied return the pension pays you on the lump sum (the break-even investment return), and how long the lump sum would last if you paid yourself the same monthly income from it. It is useful for anyone facing a pension buyout window, a job change, or retirement from a defined-benefit plan.
Payments are assumed to start immediately and arrive monthly; cost-of-living increases are applied once a year. The analysis ignores taxes (a lump sum rolled into an IRA stays tax-deferred), survivor options and the PBGC guarantee limit (for 2026, $7,789.77 a month for a single-employer plan retiree aged 65). Living longer than expected favors the annuity; dying early or earning high returns favors the lump sum.
With the default inputs, the pension value minus lump sum is −$3,381.29. Change any value above to recalculate instantly.
How to use the pension lump sum vs annuity calculator
- 1Enter the lump sum from your pension election paperwork.
- 2Enter the monthly annuity you would receive instead and the age it starts.
- 3Enter a realistic life expectancy — consider family history and health.
- 4Enter the return you could reasonably earn on the lump sum and any pension COLA.
- 5Compare the present value, break-even return and the age the lump sum would run out.
Formula and method
The present value discounts every monthly pension payment P_m back to today at the monthly equivalent of your expected investment return r, over N months from the start age to your life expectancy. Payments grow once a year by the cost-of-living adjustment. If the present value exceeds the lump sum, the pension is worth more at that return.
The implied (break-even) rate is the return that makes the present value exactly equal the lump sum, found by bisection — you would need to beat it investing on your own. The “runs out” age simulates withdrawing the same monthly income from the invested lump sum until the balance hits zero.
- P
- Monthly pension payment in the first year
- N
- Number of monthly payments to life expectancy
- r / i
- Expected annual return and its monthly equivalent
- COLA
- Annual pension increase
Worked examples
$500,000 lump sum vs $3,000 a month from 65
Discounting 276 monthly payments of $3,000 at 5% a year gives a present value of about $496,619 — within 1% of the $500,000 lump sum, and the pension’s implied return is about 4.92%. Paying yourself $3,000 a month from the lump sum at 5% would last to about age 88.3, so the choice hinges on longevity and investment skill.
Pension with a 2% COLA and a long life
With payments rising 2% a year to age 92, the pension is worth about $488,526 at a 5% discount rate — roughly $88,526 more than the $400,000 lump sum. You would need to earn about 6.88% a year to do as well investing the lump sum.
Generous buyout: $500,000 vs $1,800 a month
Withdrawing $1,800 a month ($21,600 a year) is less than the roughly $24,400 a year that $500,000 earns at 5%, so the invested lump sum never runs out. The pension’s 276 payments total only $496,800 — less than the lump sum itself — and are worth about $297,971 today, so the buyout is clearly better.
Frequently asked questions
Is it better to take a pension lump sum or monthly payments?+
The monthly pension is usually better if you expect to live longer than average, want guaranteed income, and have few other secure income sources. The lump sum can be better if your health is poor, you want to leave money to heirs, or you can invest it at a return above the pension’s implied rate.
How do I calculate the value of my pension?+
Discount each future payment back to today at a realistic interest rate and add them up — that is the present value. Plans calculate lump sums using IRS-mandated corporate bond rates and mortality tables, so when interest rates rise, lump-sum offers usually fall.
What is the break-even rate of a pension buyout?+
It is the investment return at which the lump sum could pay you exactly the same income until your life expectancy. If you are unlikely to earn more than this rate reliably, after fees, the pension offers the better deal.
Are pension lump sums taxable?+
A lump sum rolled directly into an IRA or another qualified plan is not taxed until you withdraw it. Taken as cash, it is taxed as ordinary income in the year received, with 20% mandatory federal withholding on an eligible distribution paid to you. The 10% early-distribution tax generally applies before age 59½, but not to a payout from an employer plan after you leave that employer in or after the year you turn 55 (50 for qualifying public-safety employees).
What happens to my pension if the company goes bankrupt?+
Most private-sector defined-benefit pensions in the US are insured by the Pension Benefit Guaranty Corporation up to a limit that depends on your age. For single-employer plans ending in 2026 the maximum guarantee is $7,789.77 a month at 65 as a straight-life annuity. Benefits above the limit may be reduced, which is one reason some people prefer a lump sum.
Results are estimates for educational purposes and are not financial advice. Rates, fees and terms vary — confirm with your lender or a licensed advisor before making decisions.