Future value of a regular payment stream
Level or escalating contributions, any frequency, with the timing comparison and the full schedule.
$150,000 paid in across 300 monthly contributions, plus $196,497 of growth.
- Money paid in: $150,000 (43.3%)
- Investment growth: $196,497 (56.7%)
Closed-form check: the level-annuity formula gives $346,496.98, which matches the schedule below. With an annual increase applied there is no closed form, so the schedule becomes the calculation.
| Contribution timing | Future value | Total growth | Difference | Advantage |
|---|---|---|---|---|
| End of each period | $346,497 | $196,497 | $0 | 0.0% |
| Beginning of each period | $348,229 | $198,229 | $1,732 | 0.5% |
Paying in advance is worth $1,732 here — 0.50%, which is exactly one period of growth on every payment.
Scroll the table sideways on a narrow screen to see every column.
| Contribution pattern | Final payment | Total paid in | Future value | Total growth |
|---|---|---|---|---|
| Level payment | $500 | $150,000 | $346,497 | $196,497 |
| Rising 3% a year | $1,016 | $218,756 | $461,679 | $242,924 |
$68,756 of extra contributions produce $115,182 of extra value — 1.675 per dollar, because the increases still have years left to compound.
Scroll the table sideways on a narrow screen to see every column.
| Scenario | Annual return | Future value | Growth | vs stated return |
|---|---|---|---|---|
| Lower return | 4.0% | $257,065 | $107,065 | -$89,432 |
| Stated return | 6.0% | $346,497 | $196,497 | $0 |
| Higher return | 8.0% | $475,513 | $325,513 | $129,016 |
Contributions are identical in every row: only the return assumption changes. A band is a sensitivity test, not a probability.
Scroll the table sideways on a narrow screen to see every column.
| Year | monthly payment | Starting balance | Contributions | Growth | Ending balance |
|---|---|---|---|---|---|
| 1 | $500 | $0 | $6,000 | $168 | $6,168 |
| 2 | $500 | $6,168 | $6,000 | $548 | $12,716 |
| 3 | $500 | $12,716 | $6,000 | $952 | $19,668 |
| 4 | $500 | $19,668 | $6,000 | $1,381 | $27,049 |
| 5 | $500 | $27,049 | $6,000 | $1,836 | $34,885 |
| 6 | $500 | $34,885 | $6,000 | $2,319 | $43,204 |
| 7 | $500 | $43,204 | $6,000 | $2,833 | $52,037 |
| 8 | $500 | $52,037 | $6,000 | $3,377 | $61,414 |
| 9 | $500 | $61,414 | $6,000 | $3,956 | $71,370 |
| 10 | $500 | $71,370 | $6,000 | $4,570 | $81,940 |
| 11 | $500 | $81,940 | $6,000 | $5,222 | $93,161 |
| 12 | $500 | $93,161 | $6,000 | $5,914 | $105,075 |
| 13 | $500 | $105,075 | $6,000 | $6,649 | $117,724 |
| 14 | $500 | $117,724 | $6,000 | $7,429 | $131,152 |
| 15 | $500 | $131,152 | $6,000 | $8,257 | $145,409 |
| 16 | $500 | $145,409 | $6,000 | $9,136 | $160,546 |
| 17 | $500 | $160,546 | $6,000 | $10,070 | $176,616 |
| 18 | $500 | $176,616 | $6,000 | $11,061 | $193,677 |
| 19 | $500 | $193,677 | $6,000 | $12,113 | $211,790 |
| 20 | $500 | $211,790 | $6,000 | $13,231 | $231,020 |
| 21 | $500 | $231,020 | $6,000 | $14,417 | $251,437 |
| 22 | $500 | $251,437 | $6,000 | $15,676 | $273,113 |
| 23 | $500 | $273,113 | $6,000 | $17,013 | $296,126 |
| 24 | $500 | $296,126 | $6,000 | $18,432 | $320,558 |
| 25 | $500 | $320,558 | $6,000 | $19,939 | $346,497 |
The payment column is constant because no annual increase is applied.
Scroll the table sideways on a narrow screen to see every column.