SIP Calculator

What is a Systematic Investment Plan (SIP)?

A SIP is a way to invest a fixed amount in a mutual fund scheme at regular intervals — usually monthly. You instruct your bank to auto-debit ₹5,000 or ₹10,000 on the 5th of every month, and that amount buys units of your chosen fund at the prevailing NAV. That's the whole mechanism.

AMFI data shows over 10 crore active SIP accounts in India as of 2024, with monthly SIP contributions crossing ₹25,000 crore. The model caught on because it removed two obstacles: needing a large lump sum to start, and the anxiety of timing the market.

In practice, when markets fall, your fixed ₹10,000 buys more units. When markets rise, your existing units appreciate. Over a full market cycle, this averaging effect smooths your effective purchase cost — which is why SIP suits investors who cannot predict market direction (that's all of us).

SEBI mandates that mutual funds allow SIPs with a minimum of ₹100/month, though most fund houses set practical minimums at ₹500 or ₹1,000. SIP mandates run through NACH (National Automated Clearing House) and are reversible with 30 days' notice.

The SIP Formula — How the Math Works

The future value of a SIP is calculated using this formula:

Where P = monthly SIP amount, r = monthly interest rate (annual rate ÷ 12 ÷ 100), n = total number of months (years × 12).

Worked example: ₹10,000/month SIP at 12% annual return for 10 years.

• r = 12% ÷ 12 ÷ 100 = 0.01 (1% per month)
• n = 10 × 12 = 120 months
• FV = 10,000 × [(1.01)¹²⁰ − 1] / 0.01 × 1.01
• FV = 10,000 × [3.3004 − 1] / 0.01 × 1.01
• FV ≈ ₹23,23,391

You invested ₹12,00,000 (₹10,000 × 120 months) and received ₹23,23,391 — the extra ₹11,23,391 is entirely from compounding. This is why the saying holds: the first ₹10 lakh you invest does more work than the next ₹50 lakh you save.

Power of Compounding — Time Is the Real Variable

The compounding effect in a SIP is non-linear. Doubling the investment period does not double the corpus — it multiplies it many times over. The table below shows ₹10,000/month invested at 12% annual return across different time horizons.

At 5 years, returns are 36% of invested capital. At 30 years, returns are 880% of invested capital. The money you put in during the final 5 years contributes far less than the money invested in the first 5 years — because those early investments compound for longer. This is not motivation poster content; it is arithmetic.

SIP vs Lumpsum — Which One Wins?

Neither strategy dominates unconditionally. The honest answer depends on when you invest, not just how much.

Rupee cost averaging (RCA) is the mechanism behind SIP outperformance in volatile markets. When the Nifty 50 corrected 38% in March 2020, SIP investors bought heavily at the bottom. Lumpsum investors who entered at the January 2020 peak were down 38% within weeks. The RCA effect ensures SIP investors never buy everything at the top.

However, in a consistently rising market (like 2014–2018 when Nifty went from 6,200 to 11,600), a lumpsum deployed at the start outperforms SIP because you own more units through the entire rally.

The practical rule: if you have a large corpus sitting in savings, deploy 30–40% immediately and SIP the rest over 6–12 months. This captures some upside while reducing timing risk. Do not keep the entire amount idle waiting for a "correction" — markets spend more time going up than down.

How to Choose the Right SIP Amount

The 50-30-20 rule is a reasonable starting framework: 50% of take-home for necessities, 30% for discretionary spending, 20% for savings and investments. The SIP amount should come from that 20% — plus any bonus, increment, or windfall.

A more precise approach: work backwards from your goal. Want ₹1 crore in 20 years at 12%? Our calculator shows you need ₹10,010/month. Want ₹2 crore? Double it to ₹20,020/month. This is goal-based investing, and it gives you a concrete number rather than an abstract percentage.

Age-based allocation matters too. If you are 25 years old, you can afford 80–100% equity allocation (higher-return, higher-volatility funds). At 50, shift towards 50–60% equity. This affects the expected return rate you use in projections — equity funds target 12–14% long-term; debt funds realistically deliver 6–8%.

Step-up SIP is worth considering: commit to increasing your SIP by 10% every year. On a ₹10,000 starting SIP, this means ₹11,000 in year 2, ₹12,100 in year 3, and so on. Over 20 years, this strategy can nearly double your corpus compared to a flat ₹10,000 SIP, while the annual increment feels modest at each step.

Common SIP Mistakes That Cost Real Money

Not starting early: A 25-year-old investing ₹10,000/month for 30 years at 12% accumulates ₹3.53 crore. A 35-year-old doing the same for 20 years accumulates ₹99.9 lakh. Ten years of delay costs ₹2.53 crore in final corpus — not because of the ₹12 lakh less invested, but because of the compounding years lost.

Stopping during market crashes: This is the most expensive mistake. When markets fell 25% in 2022, many investors paused SIPs. Those who continued bought units cheap and recovered faster. Stopping a SIP during a crash locks in losses and misses the recovery. The data is unambiguous — investors who stayed invested through every major Nifty correction (2008, 2011, 2015, 2020) did better than those who tried to time the exit.

Not increasing SIP annually: Inflation erodes purchasing power. A ₹10,000 SIP today has the real value of ₹6,100 in 10 years at 5% inflation. Not increasing your SIP means investing less in real terms every year. Even a 5% annual step-up keeps pace with inflation.

Ignoring expense ratios: A regular plan (bought through a distributor) might charge 1.5–2% expense ratio vs 0.1–0.5% for direct plans. On a 20-year SIP, this difference can eat 15–20% of your final corpus. Always check whether you are in a regular or direct plan, and prefer direct plans if you do not need advisory services.

Tax Implications on SIP Returns

Each SIP installment is treated as a separate investment for tax purposes. When you redeem, FIFO (First In, First Out) applies — oldest units are redeemed first.

For equity mutual funds (funds with 65%+ equity): Units held more than 12 months qualify as Long-Term Capital Gains (LTCG). LTCG above ₹1,25,000 per financial year is taxed at 12.5% (post-Budget 2024 revision from 10%). Units held 12 months or less are Short-Term Capital Gains (STCG) taxed at 20%.

ELSS (Equity Linked Savings Scheme) funds offer a ₹1,50,000 tax deduction under Section 80C but carry a mandatory 3-year lock-in per installment. The LTCG rules apply after lock-in. If you are investing in ELSS for tax saving, note that each SIP installment has its own 3-year lock-in — you cannot redeem the January 2023 installment until January 2026, regardless of when other installments were made.

For debt mutual funds (funds with less than 35% equity): Gains are added to your income and taxed at your slab rate, regardless of holding period. The indexation benefit was removed in Finance Act 2023. This makes debt MFs less attractive for long-term tax efficiency compared to alternatives like PPF or SGBs.