How SIP Returns Are Calculated — The Power of Monthly Investing

A SIP — Systematic Investment Plan — is the most popular way Indians invest in mutual funds. You invest a fixed amount every month, and over time, compounding does the heavy lifting. But how exactly are SIP returns calculated?

The formula

Each monthly installment is treated as an independent investment that grows at the expected rate for its remaining duration:

FV = P × [((1 + r)ⁿ − 1) / r] × (1 + r)

Where:

• P = Monthly investment
• r = Monthly rate of return (annual rate ÷ 12)
• n = Number of months

This is essentially the future value of an annuity formula.

Why SIP works better than lump sum for most people

1. Rupee cost averaging — You buy more units when markets are low, fewer when high
2. Discipline — Automatic monthly deduction removes emotional decision-making
3. Compounding — Returns earned each month also earn returns in subsequent months
4. Accessible — Start with as little as ₹500/month

Worked example

₹10,000/month for 15 years at 12% annual return:

Total invested: ₹10,000 × 180 = ₹18,00,000
Future value: ₹50,45,760
Wealth gain: ₹32,45,760 (180% return on invested amount)

The first ₹10,000 invested compounds for the full 15 years. The last ₹10,000 only compounds for 1 month. This is why starting early matters enormously.

What return rate to expect

• Equity mutual funds (large cap): 10–12% historically
• Mid/small cap: 12–15% (with higher volatility)
• Debt funds: 6–8%
• These are pre-tax, pre-inflation numbers

Common mistakes

• Expecting linear growth — SIP returns are exponential. The first 5 years feel slow; the last 5 years feel dramatic.
• Stopping during crashes — Market dips are when SIP works best (you buy cheap units)
• Not stepping up — Increasing SIP by even 10% yearly dramatically improves final corpus

Try the OurDailyCalc SIP calculator to project your investment growth with a year-by-year breakdown.

TL;DR

• SIP compounds each monthly installment independently
• ₹10K/month for 15 years at 12% becomes ~₹50L (from ₹18L invested)
• Start early, stay consistent, increase annually
• Market dips are your friend when investing via SIP