Finance Guide

How to Calculate SIP Returns with Monthly Investments

A clear guide to SIP future value, annual return assumptions, XIRR, and how step-up SIPs can change long-term wealth.

Updated May 29, 2026 - 7 min read

A SIP, or systematic investment plan, invests a fixed amount at regular intervals. The power of SIP investing comes from consistency, compounding, and time in the market. Calculating expected returns helps you set a realistic monthly investment target.

SIP future value formula

A common SIP future value formula is FV = P x (((1 + r)^n - 1) / r) x (1 + r). P is the monthly investment, r is the monthly expected return, and n is the number of installments.

If you assume a 12 percent annual return, the monthly rate is 12 / 12 / 100 = 0.01. A 10-year SIP has 120 monthly installments.

  • P: amount invested each month
  • r: expected monthly return
  • n: total number of monthly investments
  • FV: estimated maturity value

Example calculation

Suppose you invest 10,000 per month for 10 years at an assumed 12 percent annual return. With monthly compounding, the projected value is about 2.3 million, while the invested amount is 1.2 million.

This is only an estimate. Market returns are not fixed, and actual results can be higher or lower depending on fund performance, costs, timing, and volatility.

Why XIRR matters

XIRR is useful when investments happen on different dates or amounts change over time. It estimates the annualized return from irregular cash flows.

For a simple fixed monthly SIP, future value is enough for planning. For real portfolios with skipped months, redemptions, or extra investments, XIRR gives a cleaner view of actual performance.

Step-up SIP strategy

A step-up SIP increases the monthly investment every year. Even a 5 to 10 percent annual increase can significantly improve long-term wealth because later contributions compound on top of earlier growth.

This strategy works well when income rises over time. It also avoids the pressure of starting with a very high monthly investment immediately.

Step-by-step summary

  1. Choose your monthly investment amount.
  2. Choose an expected annual return rate.
  3. Convert the annual return to a monthly rate.
  4. Multiply years by 12 to get total installments.
  5. Apply the SIP future value formula.
  6. Compare invested amount, estimated gains, and maturity value.

Frequently asked questions

Is SIP return guaranteed?

No. SIP returns are market-linked unless you are using a guaranteed product. Mutual fund SIP projections are estimates, not promises.

What return should I assume for SIP planning?

Many planners test several scenarios such as 8 percent, 10 percent, and 12 percent. Conservative assumptions are safer for long-term planning.

Is monthly SIP better than yearly investing?

Monthly SIPs are easier to budget and can reduce timing risk. A lump sum can work well too if you already have funds and a suitable risk profile.