The five years you skip at the start cost more than any five years after
Delaying a SIP by five years does not cost you five years of contributions. It costs you the five most compounded years, which is usually about half the final corpus.
Everyone knows starting early is better. Almost nobody has looked at the size of the difference, and the size is what makes the argument.
Two people, one decision
Both invest ₹10,000 a month at 12%. Both stop at 50.
- A starts at 25. Twenty-five years of contributions: ₹30 lakh invested.
- B starts at 30. Twenty years: ₹24 lakh invested.
B put in ₹6 lakh less. At 50:
- A has about ₹1.89 crore.
- B has about ₹99 lakh.
A gap of ₹90 lakh, produced by a difference of ₹6 lakh in contributions. The five-year delay did not cost B ₹6 lakh. It cost fifteen times that.
Why the arithmetic is so lopsided
The intuition that fails here is that each year of investing is worth roughly the same as any other. It is not. Each year is worth what it compounds for.
₹10,000 invested at 25, at 12%, is worth about ₹2.9 lakh at 50 — twenty-five years of doubling. The same ₹10,000 invested at 45 is worth about ₹18,000. The first rupee is doing sixteen times the work of the last one.
Which means the years you remove from the beginning of a plan are the most valuable years in it. Everyone instinctively treats the delay as removing years from the end, where they are nearly worthless. It removes them from the front, where they are worth everything.
At 12%, money doubles roughly every six years. Over twenty-five years that is about four doublings. Over twenty, it is three. B is not missing 20% of the time — B is missing an entire doubling of everything accumulated up to that point.
Where the money actually appears
Take A's twenty-five years and split them into five-year blocks. The corpus at the end of each:
| Age | Corpus | Added in the block |
|---|---|---|
| 30 | ₹8.2 lakh | ₹8.2 lakh |
| 35 | ₹23 lakh | ₹14.8 lakh |
| 40 | ₹50 lakh | ₹27 lakh |
| 45 | ₹98 lakh | ₹48 lakh |
| 50 | ₹1.89 crore | ₹91 lakh |
The final five years add ₹91 lakh — more than the first twenty combined. The contribution in that block was ₹6 lakh, the same as in every other block.
This is the shape of the curve, and it explains almost every behavioural failure around investing. For the first decade it looks like a savings account with extra steps. The visible reward arrives at the end, long after the decisions that produced it. People give up in the flat part, which is the only part they ever see if they start late.
Catching up is expensive
Suppose B, at 30, wants to reach A's ₹1.89 crore by 50 anyway. What monthly amount does that take at 12% over twenty years?
About ₹19,100 a month — nearly double.
Delay to 35, and reaching the same figure by 50 needs roughly ₹42,000 a month. By 40, it is around ₹1,03,000 a month.
The catch-up cost does not rise linearly. It rises the way the curve does, which is why "I will invest properly once I am earning more" is such an expensive plan. The income usually does rise; it rarely rises fast enough to buy back the compounding.
What actually causes the delay
Rarely a decision not to invest. Almost always one of these:
Waiting for a lump sum. People hold cash intending to invest ₹5 lakh when they have it, rather than ₹10,000 now. The ₹10,000 invested today is worth more than ₹10,000 invested in eighteen months, and the lump sum frequently never assembles.
Waiting for a better entry point. The market always looks either too high or too uncertain. Over a twenty-five-year horizon, entry timing is close to noise; the number of years is not.
Waiting to understand it. A broad index fund requires no expertise to start. Understanding can be acquired while invested. It is far cheaper to learn with ₹10,000 a month running than to spend three years reading.
Waiting to clear debt first. Correct for anything above about 12%. For a home loan at 8.5%, doing both at once is usually better than sequencing them, precisely because the early investing years are the valuable ones.
The version that applies if you are already late
If you are forty and have not started, the arithmetic above is not an argument for despair. It is an argument for today over next year, and the gap between those two is still large.
Starting at 40 with ₹30,000 a month at 12% produces about ₹1.5 crore by 60. Starting at 41 produces about ₹1.32 crore. One year of delay, ₹18 lakh.
The most valuable year available to you is always the current one. That was true at 25 and it is still true at 45.
Open the compound interest calculator
Published by FinClamp. This guide is information, not financial advice — see the disclaimer.