Mutual Fund Returns Calculator
Estimate the maturity value of a mutual fund investment — a starting lump sum plus a monthly SIP — at any expected annual return and time horizon. Uses the standard SIP future-value formula with monthly compounding.
Maturity value
£309,748.12
- Starting amount
- £10,000.00
- Total payments
- £90,000.00
- Total contributed
- £100,000.00
- Interest earned
- £209,748.12
Maturity value = lump sum compounded monthly at the expected annual return, plus the future value of monthly SIP contributions: M = P · (1+i)^n + SIP · ((1+i)^n − 1)/i, where i = annual return / 12 and n = years × 12. Returns are projected, not guaranteed.
How to use this calculator
Enter the lump sum you are investing on day one (set to zero for a pure SIP), the amount you plan to add each month, the expected annual return on the fund, and how many years you plan to stay invested. The maturity value, total contributions, and projected gains update as you type.
How the calculation works
The calculator treats your mutual fund investment as a textbook time-value-of-money stream: a lump sum compounding monthly at the expected annual return, plus a stream of equal monthly SIP contributions. The formula is M = P · (1+i)^n + SIP · ((1+i)^n − 1)/i, where P is the lump sum, SIP is the monthly contribution, i is the monthly rate (annual return ÷ 12), and n is the total number of months (years × 12). Returns are compounded monthly and treated as ordinary annuity payments (end of month). The result is a projection only — actual mutual fund returns vary with market performance, fund expenses, and exit loads.
Worked example
Example: a £10,000 lump sum plus a £500 monthly SIP, projected at a 12% expected annual return over 15 years. Monthly rate i = 0.01, total periods n = 180. The lump sum grows to 10,000 · 1.01^180 ≈ £59,958. The SIP grows to 500 · (1.01^180 − 1) / 0.01 ≈ £249,790. Maturity value ≈ £309,748 from £100,000 of contributions (£10,000 lump sum + £90,000 of SIPs), with roughly £209,748 of projected investment gains.
Frequently asked questions
What is a mutual fund returns calculator?
A mutual fund returns calculator projects the future value of money invested in a mutual fund — either as a one-off lump sum, a recurring monthly SIP (Systematic Investment Plan), or both. It uses the standard compound-interest formula with monthly compounding and a single assumed annual return. Because mutual fund returns are not guaranteed, the result should be read as a projection given an assumption, not a forecast.
What expected return should I use?
Use a return assumption that matches the type of fund you are modelling and a time horizon long enough for short-term volatility to wash out. Broadly: cash/liquid funds 3-5%, debt/bond funds 5-7%, balanced/hybrid funds 7-10%, large-cap equity 9-11%, broad equity / index funds 10-12%, mid- and small-cap equity 11-14% (with much wider variance). These are nominal, pre-tax, before fund expenses. Subtract the fund's expense ratio (often 0.1-2.0%) and an inflation estimate if you want real, after-fee returns.
Does this match a SIP calculator?
Yes — when you set the lump sum to zero, the result is identical to a standard SIP calculator: M = SIP · ((1+i)^n − 1)/i with monthly compounding. When you set the SIP to zero, it reduces to a lump-sum-only compound interest calculation: M = P · (1+i)^n. The combined form lets you model "lump sum plus top-up SIP" in one go, which is how many real-world mutual fund plans work.
How does compounding frequency affect the result?
This calculator assumes monthly compounding, which is the convention used by most published mutual fund SIP calculators and matches the typical monthly NAV-based valuation cycle. Annual compounding at the same nominal rate produces a slightly lower maturity value; daily compounding produces a marginally higher one. The difference is small relative to the uncertainty in the return assumption itself, so monthly is a reasonable default for projection purposes.
What does this calculator NOT account for?
Four things: (1) fund fees and expense ratios — subtract them from the return assumption to model net returns; (2) entry/exit loads — typically charged on redemption, not deposit; (3) capital gains tax on redemption — varies by jurisdiction and holding period; (4) inflation — the projection is in nominal currency. For a real (inflation-adjusted) figure, subtract your expected inflation rate from the return input before computing. Returns are also assumed constant, whereas real-world mutual fund returns are volatile and path-dependent.
Are mutual fund returns guaranteed?
No. Unlike a bank deposit or fixed-rate savings product, mutual funds are market-linked investments. Past returns do not guarantee future results, and the value of your investment can go down as well as up. This calculator projects what your investment would be worth if it earned exactly your assumed return every year — useful for planning, but not a forecast. For higher-risk equity funds, you should model a range of outcomes (e.g. 6%, 10%, 14%) rather than a single number.