How this calculator works
- Step 1Deposit for 15 years₹1,50,000.00From ₹250 to ₹1,50,000 in each financial year.
- Step 2Interest each month8.2%One twelfth of the yearly rate, on the lowest balance after the 5th.
- Step 3Credit on 31 March₹12,300.00The year’s interest is added once and earns interest from April.
- Step 4Mature at 21 years₹71,82,119.17Years 16 to 21 earn interest with no new deposits.
Sukanya Samriddhi is a government small-savings account opened for a girl up to age 10. Deposits are allowed for 15 years from opening, and the account matures 21 years after opening.
Interest is worked out each month on the lowest balance between the close of the 5th and the month end. It is credited once a year, at the end of the financial year, so it compounds yearly.
The rate is a user input. It defaults to 8.2%, the rate listed for 1 October to 31 December 2026, and the same rate is applied to every year.
Worked example: the yearly maximum every April
- Interest in a year
I = r × (opening balance + deposit × k)- Balance after 15 deposit years
B₁₅ = A × (1 + r × k) × [(1 + r)^15 − 1] / r- Balance at 21 years
B₂₁ = B₁₅ × (1 + r)^6
- Adeposit each financial year ₹1,50,000.00
- ryearly rate as a decimal 8.2%
- kshare of the year the deposit earns 12 of 12 months
- Year 1 interest on the April deposit₹12,300.00
- Balance after 15 years of deposits₹44,75,989.33
- Year 16 interest, no deposit₹3,67,031.12
- Total deposited₹22,50,000.00
- Total interest₹49,32,119.17
- Estimated balance at maturity₹71,82,119.17
HDFC Bank’s published SSY calculator shows the same plan at ₹71,82,119 when rounded to the rupee. We use it as an outside check on the method.
The 5th of the month changes the answer
- Deposits
- Interest
A deposit made after the 5th misses that month, because the month’s lowest balance was set before it arrived. Monthly deposits put less money to work early in each year.
Smaller deposits and her age
- ₹50,000.00 a year₹23,94,039.72Same timing and rate, one third of the deposit.
- Opened at age 8Matures at 29The amount is the same; only her age at maturity changes.
The balance is proportional to the deposit, so one third of the deposit gives one third of the maturity. Her age at opening does not change the amount, because the term always runs 21 years from opening.
Reading the result and its limits
The result is an estimate at one fixed rate; the actual balance depends on every future quarterly rate and the dates your deposits are credited.
With a zero rate, the balance is simply your deposits: ₹22,50,000.00. Everything above that is interest, which depends on the rate entered.
The calculator does not round yearly interest to the rupee, while the account office does. A passbook can therefore differ by a few rupees. Education withdrawals and early closure are not modelled.
Other government savings schemes
Sukanya Samriddhi is one of several small-savings schemes. Each has its own rate, term and limits.
For a 15-year government-backed account, see the PPF calculator. Fixed-term options include the NSC calculator and the KVP calculator, and the college cost calculator estimates future fees.
Common mistakes
Mistake: Depositing on the 6th or later and expecting interest for that month.
Instead: Make sure the credit reaches the account by the close of the 5th.
Mistake: Thinking deposits continue for all 21 years.
Instead: Deposits stop after 15 years; the balance then earns interest until maturity.
Mistake: Paying more than ₹1,50,000.00 in a financial year.
Instead: Amounts above the limit earn no interest and are returned.
Mistake: Assuming today’s rate will apply for 21 years.
Instead: Treat the rate as an assumption and test a lower and a higher one.
Methodology and sources
Tests compare the formula with an independent day-by-day simulation of the lowest-balance rule and with a bank’s published figure.
The deposit limits, terms and interest rule come from the Sukanya Samriddhi Account Scheme, 2019, as set out in a PIB note of 21 January 2025. The rate comes from India Post’s savings-scheme page.
The rate is reviewed every quarter. This page will be checked when the next rate is announced. Source links, the review date and the financial disclaimer follow.
Read how we test our calculators, or browse more money calculators.