Understanding growing annuities
A growing annuity is a finite stream of cash flows that expand at a constant percentage rate each period over a defined horizon. Unlike standard level annuities where every installment is identical, growing annuities account for regular payment increases driven by inflation, contractual escalation clauses, scheduled salary increments, or expanding dividend payouts.
This calculator evaluates both the present value (PVGA) and future value (FVGA) of escalating cash flows, supporting both ordinary annuities (end of period) and annuities due (start of period). If your cash flows remain constant without annual increases, evaluate level payments with our annuity calculator. When focusing exclusively on long-term terminal accumulation and compounded wealth, consult the future value of growing annuity calculator. For standard constant contributions where every deposit is invested on the first day of the billing cycle, compare returns using our future value of annuity due calculator. If you are evaluating a fixed-income retirement draw phase with level scheduled withdrawals, model your depletion timeline with the annuity payout calculator.
Growing annuity formulas
Let C₁ represent the initial payment received or deposited in period 1, g denote the periodic growth rate, r represent the periodic discount or interest rate, and n represent the total number of payment intervals.
Present value of an ordinary growing annuity (r ≠ g)
When the discount rate differs from the payment growth rate, the present value discounts each escalating payment back to time zero:
Future value of an ordinary growing annuity (r ≠ g)
The future value compounds all escalating cash flows to the end of period n:
Special condition: when interest rate equals growth rate (r = g)
If the discount rate exactly matches the growth rate (r = g), the standard fraction yields a zero-denominator division. Taking the algebraic limit reveals that each cash flow discounted back to time zero simplifies to C₁ / (1 + r). Across n identical discounted periods:
Ordinary annuity vs. annuity due timing
Under an ordinary annuity, payments occur at the end of each payment period. Under an annuity due, payments occur at the beginning of each period. Because every cash flow occurs one compounding period earlier, both present value and future value are scaled by a factor of (1 + r):
Worked example: valuing a multi-year escalating contract
Suppose you are evaluating a 5-year commercial royalty or pension agreement where the initial year-end payment is $1,000. Each subsequent year, the payment increases by 3% to offset inflation, and the appropriate annual discount rate is 6%.
- Initial payment (C₁): $1,000
- Payment growth rate (g): 3.0% (0.03)
- Discount rate (r): 6.0% (0.06)
- Duration (n): 5 years
Step 1: Calculate the nominal cash payments across the 5 years:
| Year | Payment formula | Cash payment |
|---|---|---|
| Year 1 | $1,000 × (1.03)⁰ | $1,000.00 |
| Year 2 | $1,000 × (1.03)¹ | $1,030.00 |
| Year 3 | $1,000 × (1.03)² | $1,060.90 |
| Year 4 | $1,000 × (1.03)³ | $1,092.73 |
| Year 5 | $1,000 × (1.03)⁴ | $1,125.51 |
| Total nominal cash | Sum of all 5 payments | $5,309.14 |
Step 2: Apply the present value equation:
Step 3: Calculate the compounded terminal future value:
Notice that the relationship FV = PV × (1 + r)ⁿ holds exactly: $4,457.43 × (1.06)⁵ = $5,965.05. If you need to model arbitrary, irregular cash flow series that do not follow a constant growth rate, use our comprehensive discounted cash flow calculator.
Frequently asked questions
What is the primary difference between an annuity and a growing annuity?
Can the growth rate (g) exceed the discount rate (r)?
What happens if the discount rate equals the growth rate (r = g)?
How does payment frequency affect the calculation?
Does the calculator store or transmit my financial data?
Resources and references
The formulas and methods in this calculator were checked against these independent sources.