Coast FIRE India: The Number Where You Can Stop Investing

Priya is 31. She has been working at a Pune IT firm for seven years, and for the last four of those she has been investing ₹40,000 every month without fail. She has ₹22 lakhs in mutual funds and is genuinely proud of it. She should be.

But she is also tired. Tired of watching every expense, tired of saying no to weekend trips, tired of the low-level anxiety that comes from tracking a savings rate like a performance review. She has started wondering: is there ever a point where I can just... stop? Where the money I already have does the rest on its own?

The answer is yes. And it has a specific number attached to it.

What Coast FIRE Means

Coast FIRE is the corpus size at which you can completely stop making new investments — no more SIPs, no more lump sums, nothing — and still reach your full FIRE number by your target retirement age through compounding alone.

The name comes from the image of a car cresting a hill and then coasting to the destination with the engine off. You have done the hard work of climbing. Now gravity (compounding) carries you the rest of the way.

The important clarification: coasting does not mean retiring. You still work. Your salary still covers your living expenses. You simply stop the investment contributions. The corpus you have already built grows on its own at market returns, and by the time you hit your retirement age, it has grown into your full FIRE number.

For people burning out under a high savings rate, this is meaningful relief. You go from running at maximum effort — salary minus heavy savings equals a constrained life — to a pace where your income covers your actual life and you let time do the rest.

The Formula

The Coast FIRE number is simply your full FIRE number discounted back to today at your expected investment return. In other words: how much do you need right now, invested and left alone, to grow to your FIRE target in n years?

A few things worth noting about how this works in practice. First, you are not trying to predict exact returns — you are using 12% as a reasonable long-run Nifty CAGR to get a directional number. Second, the formula assumes you reinvest everything and do not withdraw during the accumulation phase. Third, the further away your retirement, the smaller your coast number — compounding does more work over more years.

This last point is counterintuitive but important. A 28-year-old with 27 years until retirement needs a far smaller coast number than a 40-year-old with 15 years. Time is the actual lever here, not the return rate.

Coast FIRE Numbers by Age and Retirement Target

The table below gives you Coast FIRE numbers for the most common scenarios: different starting ages, different FIRE targets, all assuming 12% CAGR and a retirement age of 55. These are the numbers worth bookmarking.

Assumes 12% CAGR (Nifty equity), retirement at 55, no withdrawals during accumulation. Coast numbers are rounded to one decimal.

A few things jump out of this table. First, coasting at 25 requires surprisingly little — under ₹25 lakhs even for a ₹5 crore FIRE target. That is within reach for someone who started investing early and earned decent returns on a modest salary for 4–5 years. Second, the jump from age 30 to 40 is dramatic: for a ₹3 crore FIRE target, you need ₹26L at 30 but ₹82L at 40. Every year you wait roughly costs you 12% more in required corpus. Third, the numbers are achievable — they are not requiring extraordinary incomes or extraordinary savings rates, just a head start and patience.

Priya's Numbers

Back to Priya. She earns ₹18 LPA in Pune. Her target retirement lifestyle is ₹60,000/month in today's money — a reasonable middle-class life, not extravagant. She wants to retire at 55.

Step one: calculate her full FIRE number.

Step two: calculate her Coast FIRE number. She is 31, wants to retire at 55 — that is 24 years.

Priya needs ₹17.8 lakhs to have officially coasted.

She has ₹22 lakhs.

She already coasted. Four months ago, probably. And she had no idea.

What “Coasting” Actually Looks Like in Practice

Hitting your coast number does not mean you wake up the next day and cancel all your SIPs. It means you have permission to — and you should think carefully about whether you want to.

Most people who reach Coast FIRE do one of three things:

One practical note: coasting works best when the corpus is in growth-oriented instruments — predominantly equity mutual funds — that can realistically deliver 12% over a long horizon. If a large portion is in FDs or debt funds earning 7%, your coast number is much higher (you need more upfront to compensate for lower compounding). The formula assumes you stay invested in equity for the duration.

The Catch: Inflation Eats Your Coast Number Too

Here is what this means in practice. Priya calculated her FIRE number as ₹2.18 crore based on ₹60,000/month in today's money. At 6% inflation, five years from now ₹60,000 of purchasing power costs roughly ₹80,000/month in nominal terms. That raises her FIRE number to roughly ₹2.91 crore — and her coast number (now with 19 years to retirement) becomes approximately ₹25.5 lakhs.

She still has plenty of buffer — her ₹22 lakh corpus at 12% for five years will be ₹38+ lakhs by then. But the point stands: coast numbers are not set-and-forget calculations. Recalculate every two to three years, especially if your lifestyle target changes or your expected retirement age shifts.

The practical rule: treat your coast number as the floor, not a precision target. Building a 15–20% cushion above it before you reduce contributions is sensible. Markets are not a 12% escalator every year — they are lumpy, and a bad sequence in the early coasting years can push your actual corpus well below the theoretical projection.

Coast FIRE vs Barista FIRE vs Lean FIRE

These three terms get conflated constantly. They are meaningfully different.

Coast FIRE is a milestone on the way to full FIRE — it is not a substitute for it. Barista FIRE is a semi-retirement that relies on part-time income to bridge the gap. Lean FIRE is full retirement on a minimal budget. They solve different problems for different people.

Many Indian FIRE journeys pass through Coast FIRE first: hit the coast number, ease off the savings throttle for a few years, maybe switch to a less intense job, and then cross into full FIRE at 52–55. It is a reasonable middle path for people who want the pressure to lift before they are fully ready to stop.

“The most underrated FIRE milestone is not the final number — it's the one where you can stop trying so hard, and just let time work.”

So What About Priya?

Priya opened a spreadsheet this morning expecting to feel behind. She had ₹22 lakhs and a vague sense that ₹2+ crore was a long way away.

What she found instead: she passed her coast number four months ago. Her existing corpus, left alone, will compound to her full FIRE target by the time she is 55. She does not need to invest a single additional rupee. She can cancel her ₹40,000 SIP tonight and her retirement plan stays intact.

She probably won't cancel it entirely. She might drop to ₹10,000/month — enough to stay in the habit, build a modest cushion above the coast number, and not feel like she's leaving too much to chance. She will take that trip to Goa she has been postponing for two years. She will stop flinching at restaurant menus.

The math did not change. Her FIRE plan did not change. But the pressure — that low-level background hum of not enough, not fast enough — that can be turned down now. She earned that.

If you are reading this and you have been investing steadily for several years: go run the numbers. Your coast number might already be in your rearview mirror.