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Last reviewed: 2026-06-19/Data checked: 2026-06-19
Investing Basics

What is SIP? A Plain-English Guide to Systematic Investment Plans in India

Learn what SIP is, how rupee cost averaging works with real numbers, how to use XIRR to measure returns, and how step-up SIP accelerates wealth building in India.

Quick answer

SIP is a method of investing a fixed amount at regular intervals (usually monthly) in a mutual fund. It enforces discipline, averages purchase cost across market cycles (rupee cost averaging), and removes the need to time the market.

When this matters

This is useful when you want to compare scenarios using your own numbers instead of generic rules. It is designed for Indian households using Niyamfin calculators for private, browser-side estimates.

Key numbers or assumptions

  • Rupee cost averaging: when NAV is low, your fixed amount buys more units; when high, fewer units. Over time this averages out the purchase cost.
  • SIP returns are measured using XIRR (extended internal rate of return), not simple or CAGR, because cash flows happen at different times.
  • Step-up SIP (increasing the amount by 10–15% annually) significantly boosts the final corpus without requiring a large initial commitment.

Example calculation

₹5,000/month SIP for 15 years at 11% p.a. assumed return → corpus ≈ ₹23.9L. Same SIP with 10% annual step-up → corpus ≈ ₹44.5L. The step-up nearly doubles the outcome.

Use the calculator

Want to estimate this with your own numbers? Use the relevant Niyamfin calculators below.

Common mistakes

  • Stopping SIP during market falls — these are exactly the months that buy more units at lower cost.
  • Measuring SIP return as (current value − invested) ÷ invested — this ignores the timing of each instalment.
  • Starting a very large SIP that is unsustainable — start small and step up.

What to do next

Use the SIP calculator to estimate corpus for different amounts and horizons. Then try the step-up SIP calculator to see how a 10% annual increase changes the outcome.

Data sources checked

Data last checked: 2026-06-19

Disclaimer

This article is for general education only. It does not provide financial, investment, tax, insurance, lending, or legal advice and should not be used as the basis for financial decisions.

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