What is a step-up (top-up) SIP?
A step-up SIP, also called a top-up SIP, is a systematic investment plan whose instalment increases at fixed intervals instead of staying flat for the entire tenure. A level SIP of ₹10,000 stays at ₹10,000 in year 15; a step-up SIP that starts at ₹10,000 and rises 10% a year reaches ₹37,975 a month by year 15. The idea is to let contributions move with income over time rather than locking them at the amount affordable on day one.
How this SIP calculator with annual increase works
The calculator treats the investment as a chain of one-year level SIPs. Within a year the monthly amount is constant; it changes only after every 12 instalments. Specifically:
- Step-up timing: the instalment rises once every 12 months, starting from month 13. Year 1 is paid at the starting amount.
- Percentage, compounded: the increase is a percentage of the previous year's instalment, so a 10% step-up goes ₹10,000 → ₹11,000 → ₹12,100, not ₹10,000 → ₹11,000 → ₹12,000. Year y's instalment is P × (1 + s)y−1.
- Monthly compounding at an effective rate: the annual return R is converted to an equivalent monthly rate i = (1 + R)1/12 − 1. At 12% this is about 0.9489% a month, so 12 months of growth equal exactly 12%.
- End-of-month contributions: each instalment earns returns from the month after it is paid; the 12th instalment of a year earns nothing by year end. This is slightly more conservative than the start-of-month convention used on our SIP calculator.
Each year's block is valued at year end and then compounds untouched until maturity:
FV = Σy=1..Y P(1 + s)y−1 × ((1 + i)12 − 1) / i × (1 + R)Y−y
- P = starting monthly SIP; s = annual step-up (decimal)
- i = effective monthly rate; R = annual return (decimal)
- Y = total years; y = year index
Total invested is simply the sum of 12 × each year's instalment. See the step-up SIP methodology page for assumptions and sources.
How to use the SIP calculator with annual increase
- Starting monthly SIP: the instalment you pay in year 1.
- Annual step-up (%): how much the instalment rises each year. 10% turns ₹10,000 into ₹11,000 in year 2.
- Expected annual return (%): an assumption, not a forecast. Try a few values to see the range.
- Investment period: the number of years you keep paying. Set the step-up to 0% to compare with a SIP that never increases.
Worked example: ₹10,000 SIP with a 10% annual increase vs a flat SIP
Take a starting SIP of ₹10,000, a 10% annual step-up, an assumed 12% annual return and 15 years. Year 1's twelve instalments of ₹10,000 are worth ₹1,26,465 at the end of that year. Repeating the block for every year and compounding gives:
- Step-up SIP: invested ₹38,12,698, value ₹81,96,939, gain ₹43,84,241.
- Flat SIP of ₹10,000 (0% step-up): invested ₹18,00,000, value ₹47,14,578, gain ₹29,14,578.
The step-up version ends ₹34,82,361 higher, but ₹20,12,698 of that gap is extra money contributed. The rest comes from returns on those extra contributions. Because the larger instalments arrive late, they have less time to compound, so the step-up SIP's gain is a smaller share of its final value than the flat SIP's.
Year-by-year schedule
| Year | Monthly SIP that year | Total invested to date | Value at year end |
|---|---|---|---|
| 1 | ₹10,000 | ₹1,20,000 | ₹1,26,465 |
| 2 | ₹11,000 | ₹2,52,000 | ₹2,80,752 |
| 3 | ₹12,100 | ₹3,97,200 | ₹4,67,465 |
| 4 | ₹13,310 | ₹5,56,920 | ₹6,91,886 |
| 5 | ₹14,641 | ₹7,32,612 | ₹9,60,070 |
| 6 | ₹16,105 | ₹9,25,873 | ₹12,78,951 |
| 7 | ₹17,716 | ₹11,38,461 | ₹16,56,466 |
| 8 | ₹19,487 | ₹13,72,307 | ₹21,01,686 |
| 9 | ₹21,436 | ₹16,29,537 | ₹26,24,977 |
| 10 | ₹23,579 | ₹19,12,491 | ₹32,38,172 |
| 11 | ₹25,937 | ₹22,23,740 | ₹39,54,770 |
| 12 | ₹28,531 | ₹25,66,114 | ₹47,90,162 |
| 13 | ₹31,384 | ₹29,42,725 | ₹57,61,883 |
| 14 | ₹34,523 | ₹33,56,998 | ₹68,89,900 |
| 15 | ₹37,975 | ₹38,12,698 | ₹81,96,939 |
Comparing step-up rates (₹10,000 start, 12%, 15 years)
| Annual step-up | Monthly SIP in year 15 | Total invested | Value after 15 years | Gain |
|---|---|---|---|---|
| 0% | ₹10,000 | ₹18,00,000 | ₹47,14,578 | ₹29,14,578 |
| 5% | ₹19,799 | ₹25,89,428 | ₹61,32,897 | ₹35,43,469 |
| 10% | ₹37,975 | ₹38,12,698 | ₹81,96,939 | ₹43,84,241 |
| 15% | ₹70,757 | ₹57,09,649 | ₹1,12,27,965 | ₹55,18,316 |
Illustrative only: a constant 12% annual return, end-of-month contributions and no costs or taxes. Monthly SIP figures are rounded to the nearest rupee. Real returns vary.
How step-up rate relates to income growth
A useful way to read the step-up input is as a statement about the share of income going into the SIP. If the step-up equals the growth rate of take-home pay, the SIP stays a constant percentage of income. A step-up above income growth means the SIP takes a rising share each year; a step-up below it means a falling share.
The compounding of the step-up itself matters over long horizons: at 10% a year the instalment is about 3.8× the starting amount by year 15, and at 15% it is about 7.1×. Income rarely rises in a straight line (job changes, career breaks and one-off bonuses all intervene), so it can help to run the calculator at a few different step-up rates and see how sensitive the result is.
How fund houses implement SIP top-up
In practice, top-up is a facility registered with the SIP mandate, and terms differ between AMCs. As of October 2026, common features include:
- Fixed amount or percentage: some AMCs allow only a fixed rupee increase; others also offer a percentage top-up. SBI Mutual Fund, for example, describes its facility as a fixed-amount top-up with a ₹500 minimum, in multiples of ₹500.
- Frequency: half-yearly or yearly top-up is typical. SBI Mutual Fund offers both for monthly SIPs and defaults to half-yearly if no frequency is chosen.
- Cap and changes: some AMCs let investors set a maximum instalment or a top-up end date. At SBI Mutual Fund, top-up details cannot be modified after enrolment; changing them requires cancelling and re-registering the SIP.
This calculator models only a yearly percentage step-up with no cap. A fixed-amount top-up grows contributions linearly, so after the first increase it falls behind a percentage step-up that starts with the same first increment (₹1,000 a year versus 10% of ₹10,000, for example).
What this calculator does not model
- Expense ratio: fund costs are deducted from the NAV, so the return entered should be thought of as net of costs.
- Tax: as of October 2026, long-term gains on equity-oriented fund units (held over 12 months) are taxed at 12.5% on the amount above ₹1.25 lakh in a financial year, and short-term gains at 20%, plus surcharge and cess. Each instalment buys units with its own holding period, so late, larger top-up instalments may still be short-term at redemption.
- Top-up caps and fixed-amount top-ups: the step-up continues uncapped for the full tenure.
- Inflation: all values are nominal rupees.
- Volatility: returns are a constant rate. In a step-up SIP the largest instalments come at the end, so returns in the final years carry more weight than in a flat SIP.
Related calculators
- SIP Calculator - project a level monthly SIP with optional inflation adjustment.
- Lumpsum Calculator - see how a one-time investment compounds over the same horizon.
- PPF Calculator - model yearly PPF deposits at the government-notified rate.
- Net Worth Calculator - place a projected corpus alongside your other assets and liabilities.