A worked example: ₹1,50,000 deposited in SCSS
Put ₹1,50,000 into a Senior Citizen Savings Scheme account as a one-time lump-sum deposit, and at the current 8.2% p.a. rate it generates ₹12,300 in annual interest, paid out as ₹3,075 every quarter. Over the standard 5-year tenure that comes to ₹61,500 in total interest, with the ₹1,50,000 principal returned in full at maturity — a total maturity amount of ₹2,11,500.
The same ₹1,50,000, invested yearly in SSY instead
Now put the same ₹1,50,000 into a Sukanya Samriddhi Yojana account instead — not as a single deposit, but as the annual contribution made every year for 15 years (this is the SSY annual cap, so it is the largest such comparison the two calculators can share). Total deposits reach ₹22,50,000 over those 15 years, and at the same 8.2% p.a. rate, compounded annually through the full 21-year term, the account earns ₹49,32,119.17 in interest — a projected maturity amount of ₹71,82,119.17.
The formula difference: simple payout vs compounding accumulation
The ₹2,11,500 SCSS figure and the ₹71,82,119.17 SSY figure are not directly comparable results from the same input — they come from different formulas answering different questions. SCSS takes one ₹1,50,000 deposit and applies simple interest (principal × 8.2%, divided into quarterly payouts) for 5 years, always paying the interest out rather than reinvesting it. SSY instead takes ₹1,50,000 deposited fresh every year for 15 years and compounds the entire growing balance at 8.2% annually for 21 years, including 6 years after deposits stop. One formula multiplies a fixed sum by a rate five times over; the other repeatedly adds new money to a balance that is itself compounding.
Why comparing the numbers alone can mislead
SCSS and SSY exist to solve different problems for different people. SCSS is open only to residents aged 60 and above (55+ for voluntary retirees, any age for retired defence personnel) and is designed to convert a retirement corpus into steady quarterly income over 5 years, with the original capital protected and returned at the end. SSY is open only for a girl child under age 10, and is designed to build up an education or marriage fund over the long 21-year horizon by encouraging small annual contributions early in her life. The ₹71,82,119.17 SSY maturity figure looks far larger than the ₹2,11,500 SCSS figure mainly because it represents 15 years of fresh contributions compounding for 21 years, against one deposit paying out over 5 — not because SSY is the "better" scheme. Choosing between them should follow eligibility and purpose, not which raw number is bigger.