Annuity Calculator

How this annuity calculator works

This annuity calculator estimates how much an annuity is worth at the end of its accumulation phase, the years when you are still paying in and it is growing. Enter an initial deposit, any yearly or monthly contributions, a fixed annual growth rate, and the number of years. The calculator adds each contribution on schedule, credits growth every month, and reports the end balance along with how much of it came from your money and how much from growth.

The growth rate is treated as an annual rate that compounds once a year. To credit growth monthly, the calculator converts it to the equivalent monthly rate, so twelve months of growth equal exactly one year at the rate you entered:

Monthly rate = (1 + annual rate)^(1/12) − 1

A $25,000 initial deposit plus $6,000 at the beginning of every year, growing at 5% a year for 15 years, ends with $187,918.16: $25,000 of initial deposit, $90,000 of contributions, and $72,918.16 of growth.

Annuity due vs. ordinary annuity

The timing choice decides when each contribution goes in. With an annuity due, contributions are made at the beginning of each period, so every payment earns growth for the full period. With an ordinary annuity, contributions arrive at the end of each period and the last one earns nothing. Yearly contributions follow the same rule: at the beginning of each year for an annuity due, or at the end of each completed year for an ordinary annuity.

In the example above, switching to end-of-year contributions lowers the end balance to $181,444.59, about $6,500 less, because each $6,000 payment grows for one year less.

Reading the accumulation schedule

The yearly schedule shows the contributions made during each year, the growth credited that year, and the balance at year end. Switch to the monthly schedule to see every month. If the length is not a whole number of years, the last row covers only the remaining months. A leftover fraction of a month, such as the 0.6 month in 3.3 years, earns growth but gets no contribution, and appears as a final monthly row. The chart compares the balance with the money you put in, so the gap between the two lines is the growth.

Frequently asked questions

What is the annuity formula for future value?

For level payments at the end of each period, future value = payment × ((1 + r)ⁿ − 1) ÷ r, where r is the rate per period and n is the number of periods. For an annuity due, multiply that result by (1 + r). Add the initial deposit grown by (1 + r)ⁿ. This calculator does the same thing month by month, which also handles a mix of yearly and monthly contributions. At a 0% rate the formula does not apply because it divides by zero; the end balance is simply the initial deposit plus all contributions.

What is a fixed annuity calculator?

A fixed annuity pays a set interest rate, so its growth can be projected with a single rate like the one this calculator uses. Variable and indexed annuities change with the market, so a fixed rate only gives a rough average for them.

Is this an annuity payout calculator?

No. It covers the accumulation phase only and does not estimate the income payments an insurer would pay from the balance. Payouts depend on your age, the payout option you choose, and the insurer's rates, so ask for a quote on the end balance shown here.

Does an annuity grow tax-free?

Growth in an annuity is tax-deferred, not tax-free. You pay no tax on the gains until you withdraw money or receive income payments. The end balance here is before any taxes, surrender charges, or tax penalties on early withdrawals.

Limitations

The calculator assumes the same growth rate every year and does not subtract fees such as mortality and expense charges, administrative fees, or rider costs. Actual contracts may credit interest on a different schedule. Treat the result as an estimate, not a quote or financial advice.