Annuity Payout Calculator
1Your Annuity
2Payout Period
Breakdown
What Is an Annuity Payout Calculator?
An annuity turns a pile of money into a stream of income: you hand an insurer a lump sum, and it pays you a fixed amount every month while crediting interest on whatever hasn’t been paid out yet. This calculator answers the natural question — “how much per month would my money generate?” Enter the principal, an annual interest rate, and a payout period in years, and it returns the level monthly payment, the total you’d collect over the full term, and how much of that total is interest rather than your own money coming back.
How It Works
The calculator uses the standard annuity-immediate formula — the same math behind mortgage payments, run in reverse. Instead of paying down a loan, the insurer pays down your principal, with interest accruing on the declining balance:
Monthly payment, where P is the principal, i is the monthly rate (annual rate ÷ 12), and n is the number of monthly payments:
PMT = P × i ÷ [1 − (1 + i)−n]Early payments are mostly interest sitting on a large balance; later payments are mostly principal being returned. By the final month, the balance reaches exactly zero. A higher rate or a longer period both raise the total collected, but more years also means smaller monthly checks, spread thinner.
Worked Example: $500,000 Over 20 Years at 5%
Annuitize $500,000 at a 5% annual rate over 20 years. The monthly rate is 5% ÷ 12 ≈ 0.4167%, across 240 payments. The formula yields a payment of about $3,299.78 a month. Over the full term you’d collect roughly $791,947 — your $500,000 back plus about $291,947 of interest earned on the declining balance. Shrink the deal to $250,000 at 4.5% for 15 years and the payout becomes about $1,912.48 a month, roughly $344,247 in total.
Fixed-Period vs. Lifetime Annuities
This calculator models a fixed-period (period-certain) annuity: payments run for an exact number of years, then stop, whether or not you’re around to spend them — any remaining certain payments typically go to a beneficiary. A lifetime annuity is a different contract: it pays as long as you live, however long that is. Insurers price lifetime payouts using mortality tables, pooling everyone’s longevity risk, so the quote depends on your age and can’t be reproduced by this formula. Lifetime versions protect against outliving your money but usually offer a lower monthly amount at younger ages. Use this tool to understand the mechanics, then compare real quotes side by side.
Common Mistakes to Avoid
First, don’t compare a fixed-period quote against a lifetime quote as if they were the same product — one has an end date, the other doesn’t. Second, remember inflation: a level $3,300 payment buys noticeably less in year 20 than in year 1, and inflation-adjusted riders cost real money. Third, annuitization is usually irreversible — once the lump sum becomes a payment stream, you generally can’t get the principal back for emergencies. Finally, taxes on annuity income depend on how the annuity was funded. This calculator provides educational estimates only, not financial or tax advice — review any annuity contract with a qualified professional before signing.
Frequently Asked Questions
Why is the monthly payout higher than the interest the principal earns?
Because each payment includes a slice of your own principal coming back, not just interest. A fixed-period annuity is designed to spend the balance down to zero by the final payment — that’s why $500,000 at 5% pays about $3,300 a month instead of the roughly $2,083 that interest alone would generate.
What happens if I die during a fixed-period payout?
With a period-certain annuity, the remaining guaranteed payments typically continue to your named beneficiary until the term ends. That’s a key difference from a pure lifetime annuity, where payments generally stop at death unless you bought a guarantee rider.
Would a lifetime annuity pay more or less per month?
It depends mostly on your age. A lifetime annuity might pay less per month than a 20-year fixed payout for a younger retiree, because the insurer may be on the hook for 30+ years. At older ages, lifetime quotes can beat fixed-period ones. Only real quotes, priced on current rates and mortality tables, can say.
Is annuity income taxable?
Generally some or all of it is. Annuities bought with pre-tax retirement money are typically fully taxable as income, while those bought with after-tax dollars are taxed only on the earnings portion of each payment. The rules are intricate — consult a tax professional; this calculator is educational only.