Immediate Annuity Calculator: Estimate Guaranteed Retirement Income
Use this guide to understand the assumptions, inputs, results, and next steps behind the calculator.
Created by Luis Gonzalez · Last updated September 18, 2026
An immediate annuity converts a lump sum into income that typically begins soon after purchase. This calculator estimates monthly payments from a single-life or joint-life payout using your purchase amount, payout rate, and joint-life reduction. It also estimates the age when cumulative payments equal the purchase price and total payments through your assumed life expectancy.
Annuity quotes vary by insurer, contract terms, payout option, interest rates, age, and state. The calculator’s payout rate is an assumption, not a current quote. Compare the estimate with a retirement annuity calculator or broader annuity calculator before considering how an annuity fits into a retirement-income plan.
Default example: $250,000 at age 65
The default assumptions are a $250,000 purchase, age 65, a 6.5% payout rate, a 15% joint-life reduction, and payments modeled through age 90. The calculator reports a single-life payment of $1,354 per month, a joint-life payment of $1,151 per month, and break-even ages of 81 and 84, respectively.
The single-life annual payment is $16,250. Dividing by 12 gives $1,354.17, rounded to $1,354 monthly. Over 25 modeled years, total single-life payments are $406,250. The joint calculation reduces the annual payment to $13,812.50, rounded to $13,813, and estimates $345,313 in total joint-life payments.
Single-life annual payment = $250,000 × 6.5%
= $16,250
Single-life monthly payment = $16,250 ÷ 12
= $1,354.17
= $1,354 rounded
Joint-life monthly payment = $16,250 × (1 - 15%) ÷ 12
= $1,151.04
= $1,151 rounded
The simple break-even calculation divides the purchase amount by annual income and rounds up to a whole year. For single life, $250,000 ÷ $16,250 is about 15.38 years, so the model rounds to 16 years after age 65: age 81. For joint life, the lower payment takes longer to equal the purchase price, producing a break-even age of 84. This is a payment-total comparison, not an investment-return calculation that accounts for interest, inflation, or what the unused purchase amount could have earned elsewhere.
Single-life and joint-life tradeoffs
A single-life annuity generally pays while one covered person is alive. A joint-life annuity can continue payments while either covered person is alive, depending on the contract’s survivor percentage and terms. In this calculator, the joint option is represented by a flat reduction percentage. It does not model every survivor-benefit design or guarantee a specific insurer’s quote.
The default joint option pays $203 less per month than the single-life option ($1,354 minus $1,151). The tradeoff is lower starting income in exchange for payments designed to continue for a second person under the contract. If a spouse or partner relies on the income, compare the survivor protection with other resources, such as Social Security survivor benefits, pensions, and savings.
| Scenario to test | Change one input | Likely effect |
|---|---|---|
| Smaller purchase | $250,000 to $200,000 | Reduces estimated single and joint monthly payments |
| Higher payout assumption | 6.5% to 7% | Increases modeled payments, but is not a guaranteed quote |
| Larger joint reduction | 15% to 25% | Reduces joint payment relative to single life |
| Shorter assumed lifespan | Age 90 to 85 | Reduces modeled total lifetime payouts and changes the comparison |
A high payout rate is not automatically a better deal. It can reflect insurer pricing, age, payout design, and market conditions; it may also come with less flexibility or different guarantees. Obtain quotes with matching terms before comparing products.
Inflation, taxes, and what the model leaves out
The calculator accepts an inflation input, but its payout and lifetime-total formulas do not increase payments for inflation or adjust them into today’s dollars. Treat the estimated payments as fixed nominal amounts in this model. With 2.5% inflation, the same dollar payment would generally buy less over time, even though the calculator does not reduce its displayed payment for that loss of purchasing power.
The calculator also estimates after-tax income using a simplified exclusion ratio. The default tax rate is 22%, and the reported after-tax monthly estimates are $1,240 for single life and $1,081 for joint life. Actual taxation depends on whether the annuity is purchased with qualified or nonqualified funds, the contract’s tax basis, and the applicable tax rules. The model’s tax estimate is not tax advice. The IRS explains general annuity and pension tax rules.
Before comparing a single premium annuity with other choices, review liquidity needs, surrender provisions, insurer financial strength, and the contract’s death-benefit terms. An immediate annuity typically exchanges access to a lump sum for promised payments under the contract. A deferred income annuity calculator can help explore income that starts later, while an IRA annuity calculator focuses on annuities held in an IRA.
Formula: payments and break-even age
The payout-rate method is a simplified estimate. A real quote may use insurer pricing factors rather than a stated percentage.
Annual single-life income = purchase amount × payout rate
Annual joint-life income = annual single-life income
× (1 - joint reduction percentage)
Break-even age = current age
+ round up(purchase amount ÷ annual payment)
Total lifetime payouts = annual payment
× (life expectancy - current age)
The model uses at least one payout year. Its total payout calculation does not discount future payments, add investment returns to the original purchase amount, or account for payments stopping at death under a single-life option.
Compare an annuity with other retirement-income sources
An annuity can provide predictable payments, but it is only one way to meet retirement spending needs. Compare the estimated payment with a lifetime annuity calculator, investment annuity calculator, or annuity surrender charge calculator if you are evaluating different contract structures.
A 4% rule withdrawal calculator can compare portfolio withdrawals with annuity income, although investment withdrawals are not guaranteed. A bucket strategy calculator can help model liquid reserves alongside long-term assets. For an overall plan, estimate retirement spending with a retirement needs calculator and test how long assets might last with a how long will my money last calculator.
Frequently asked questions
What does the break-even age mean?
It is the age when cumulative modeled payments equal the purchase amount, without adjusting for inflation, investment returns, taxes, or the value of a survivor benefit. It does not show when an annuity becomes profitable in every financial sense.
Does joint life always mean the surviving spouse receives the full payment?
No. Survivor percentages and payment options vary by contract. This calculator applies the entered joint reduction but does not specify all possible continuation terms. Review the actual quote and contract.
Is the 6.5% payout rate guaranteed?
No. It is a calculator assumption. A guaranteed payment amount is set by an insurer’s actual quote and contract, not by this estimate.
Should I choose a single-life or joint-life payout?
A single-life option may provide more income while the annuitant is alive; a joint option may continue income for a surviving covered person but often starts lower. Compare the income reduction with the survivor’s other resources and expected expenses.
Does the calculator account for inflation?
No. Although it accepts an inflation input, the displayed payment formulas do not adjust payments for inflation. A fixed nominal payment can lose purchasing power over time.
Are the after-tax estimates exact?
No. The default estimates apply a simplified tax calculation and a 22% tax-rate assumption. Tax treatment depends on the contract and funding source, so use the results only as an illustration.
Next steps
Use the estimate to compare payout designs, then request insurer quotes with the same purchase amount, payment start date, survivor terms, and inflation features. Check liquidity and tax treatment before deciding how much of your retirement savings, if any, to exchange for annuity income.