What the Coast FIRE Grid Shows

Coast FIRE is the moment you have enough invested that compound growth alone — with zero further contributions — will reach your full FIRE number by the time you retire. After that point you still need income to cover today's living costs, but you never have to save for retirement again. The grid puts this on one screen: rows are your current age, columns are the annual spending you want your portfolio to support, and each cell is the amount you'd need invested today to coast to that lifestyle by your retirement age.

Why Younger Ages Need So Much Less

Read any column top to bottom and the numbers shrink dramatically toward younger ages. That's compounding doing the heavy lifting. A dollar invested at 30 has 35 years to grow before a 65 retirement; a dollar invested at 55 has only 10. At a ~4.4% real (after-inflation) return, money roughly triples over 35 years but grows only about 55% over 10 — so the same retirement target needs a far smaller "coast" balance when you're young. This is why hitting Coast FIRE early is so powerful: it can happen in your 30s and quietly changes every career decision that follows.

How Each Cell Is Calculated

The math is the standard FIRE target discounted back to today. First, the FIRE number for a given lifestyle is annual spending divided by your safe withdrawal rate (4% by default, i.e. 25× spending). Then that future target is discounted to the present using your real return over the years remaining until retirement: coast number = (annual spending ÷ withdrawal rate) ÷ (1 + real return)^(retirement age − current age). Real return uses the Fisher relationship — (1 + nominal) ÷ (1 + inflation) − 1 — so every number in the grid is in today's dollars and stays comparable over time.

Using the Grid for Real Decisions

Find your age row and the spending column closest to your planned retirement lifestyle, then compare the cell to what you actually have invested. Already past it? You've hit Coast FIRE — you could downshift, take a lower-paying but more enjoyable job, or stop retirement contributions and redirect that money to nearer-term goals. Not there yet? The grid shows exactly how the target falls each year you keep investing, and how choosing a leaner retirement lifestyle (a column to the left) brings Coast FIRE within reach sooner.

Canadian Context and Limits

This grid is portfolio-only and deliberately simple, which makes it a clean planning reference — but real Canadian retirements are friendlier than the raw numbers suggest. CPP and OAS will eventually cover a meaningful slice of your spending (often $15,000–$25,000 per person per year from 65), which effectively lowers the portfolio you need for the years after those benefits start. It also ignores taxes, sequence-of-returns risk, and the RRSP/TFSA/FHSA account mix. Treat the grid as a fast orientation tool, then use TrackMoola's FIRE Levels calculator and Retirement Income Projector to layer in government benefits and account-specific tax treatment.