Annuity Future Value Calculator
Project the future value of regular payments — with or without a starting balance — using the standard ordinary-annuity and annuity-due formulas.
Future value
£200,903.01
- Starting balance grown
- £0.00
- Contributions grown
- £200,903.01
- Total contributions paid in
- £72,000.00
- Interest earned
- £128,903.01
- Number of periods
- 360
Ordinary annuity future value: FV = PMT · ((1+r)^n − 1)/r + PV · (1+r)^n. r is the period rate (annual rate ÷ periods per year) and n is total periods. Matches Excel =FV(rate, nper, -PMT, -PV, 0).
How to use this calculator
Enter any starting balance you already have (set to 0 for a pure-contribution plan), the amount you will add each period, the nominal annual interest rate, and the term in years. Pick how often payments occur and whether they land at the end or start of each period. The future value updates as you type.
How the calculation works
The calculator combines two textbook time-value-of-money formulas. The starting balance grows as a lump sum: PV · (1+r)^n. The stream of payments grows as an annuity: PMT · ((1+r)^n − 1)/r. r is the period interest rate (annual rate ÷ periods per year) and n is the total number of periods. For "start of period" timing (annuity due), the whole annuity result is multiplied by (1+r) because each payment gets one extra period of growth. These match Excel's =FV(rate, nper, -PMT, -PV, type) with type=0 (end) or type=1 (start).
Worked example
Saving $200 a month for 30 years at a 6% nominal annual rate (monthly compounding, end of period). Period rate r = 0.06/12 = 0.005, periods n = 360. Annuity factor = ((1.005)^360 − 1)/0.005 ≈ 1004.5150. Future value = 200 · 1004.5150 ≈ $200,903.01 from $72,000 of contributions — $128,903.01 of compound interest. Switching to start-of-period payments multiplies the result by 1.005, giving ≈ $201,907.52.
Frequently asked questions
What is the future value of an annuity?
The future value of an annuity is the amount a series of equal periodic payments will be worth at the end of the term, after every payment has been invested and earned interest at a constant rate. It answers the practical question "if I save this much per month for this many years, what will I end up with?" — and unlike compound interest on a lump sum, it accounts for each payment compounding for a different length of time (the first payment compounds for the full term, the last one barely at all).
What is the difference between an ordinary annuity and an annuity due?
Ordinary annuity payments arrive at the end of each period (standard for savings plans, bond coupons, and most loan-style products). Annuity-due payments arrive at the start of each period (standard for rents, leases, and some insurance and pension products). At the same rate, term and payment, an annuity due always has a higher future value — by exactly a factor of (1 + r), where r is the period rate — because every payment gets one extra period of compounding before the end date. This calculator handles both via the "Payment timing" selector.
Why does the calculator ask for a starting balance?
Most real savings questions are not pure annuities. You already have something — an existing 401(k) balance, a small ISA pot, a savings account with a few thousand in it — and you plan to add to it over time. The starting balance grows on its own as a compound-interest lump sum, while your contributions grow as an annuity. Adding the two parts gives the realistic projection. Set the starting balance to 0 for the textbook annuity case.
How is this different from a compound interest or savings calculator?
It is the same family of math. A pure compound-interest calculator typically handles only a starting lump sum. A savings calculator usually adds regular contributions but rarely lets you switch between end-of-period and start-of-period timing. The annuity future value calculator is the explicit form: it makes the timing convention (ordinary vs. due) and the role of each input visible, which matters when you are checking a quote, modelling a lease, or matching a textbook example.
Should I enter the nominal rate or the effective rate?
Enter the nominal annual rate — the headline rate most providers quote. The calculator divides it by the number of compounding periods per year to get the period rate, matching the convention used by finance textbooks and spreadsheet TVM functions. If your product quotes only an effective annual rate (EAR or APY), convert with nominal = m · ((1 + EAR)^(1/m) − 1), where m is periods per year. For a monthly-compounded 6.17% EAR, the equivalent nominal rate is roughly 6.00%.
What about taxes and inflation?
The result is nominal — pounds, dollars or euros at the end, in current money. To estimate real purchasing power, deduct your expected inflation rate from the rate you enter (a 7% nominal rate with 2% inflation is roughly 5% real). For tax, the calculator assumes growth is sheltered, e.g. inside an ISA, IRA, 401(k) or pension wrapper. For a taxable account, deduct your marginal rate from each period's interest. Annuity products themselves have specific tax treatment that varies by jurisdiction — this calculator is pure TVM, not product-specific.