Formula
maturity = Σ P × (1 + r ÷ n)^(n × (months remaining) ÷ 12) over every monthly deposit
- P — monthly deposit
- r — annual rate as a decimal
- n — compounding periods per year
Each deposit grows for as long as it remains in the account; the maturity amount is the sum of them all.
Worked example
5,000 a month for 24 months at 6.5%
- Monthly deposit
- 5,000
- Interest rate per year
- 6.5 %
- Tenure
- 24
- Tenure in
- Months
- Interest is compounded
- Quarterly (most Indian banks)
- Currency symbol
- ₹ Rupee (INR)
Maturity amount
₹1,28,425.30
Total deposited: ₹1,20,000.00
Interest earned: ₹8,425.30
Number of deposits: 24
How it works
Depositing 5,000 a month for 24 months at 6.5% with quarterly compounding gives a maturity of about 1,28,425.30 on 1,20,000 deposited. The first deposit earns interest for the full 24 months, the last for just one, so the average money is only invested for about half the term.
Deposits are assumed to be made at the start of each month. Banks and post offices publish their own maturity tables and can differ slightly, so confirm with yours. Lump-sum deposits are covered by the FD Calculator, and market-linked monthly investing by the SIP Calculator; see Compound Interest Calculator for the general idea.
Assumptions and limits
- Equal monthly deposits at the start of each month, none missed.
- No tax is deducted.