Coast FIRE is one of the most achievable milestones in the FIRE spectrum. The concept: save aggressively until you have enough invested that compound growth alone will carry your portfolio to your retirement goal by traditional retirement age. After that point, you only need to cover current living expenses — you "coast" to retirement.
How Coast FIRE Works
The formula: Coast FIRE Number = FIRE Target ÷ (1 + r)^n
Where r = annual return rate, n = years until retirement.
FIRE target: $1,500,000 | Retirement age: 65 | Years to grow: 30 | Expected return: 7%
Coast FIRE = $1,500,000 ÷ (1.07)^30 = $1,500,000 ÷ 7.61 = $197,000
If you have $197,000 invested at 35 and never contribute another dollar, it grows to $1,500,000 by age 65.
Coast FIRE Numbers by Age (Targeting $1,500,000 at 65)
Assuming 7% average annual return:
| Current Age | Years to Grow | Coast FIRE Number |
|---|---|---|
| 25 | 40 years | $103,000 |
| 30 | 35 years | $144,000 |
| 35 | 30 years | $197,000 |
| 40 | 25 years | $277,000 |
| 45 | 20 years | $388,000 |
Adjusting Coast FIRE for CPP and OAS (Canada)
If CPP and OAS will provide $23,000/year and you need $60,000/year total, your portfolio only needs to generate $37,000/year. Your FIRE target becomes $37,000 × 25 = $925,000 — not $1,500,000.
At a $925,000 FIRE target, Coast FIRE at age 35 = $925,000 ÷ (1.07)^30 = $121,500. A far more accessible milestone.
Coast FIRE vs Barista FIRE
| Coast FIRE | Barista FIRE | |
|---|---|---|
| Portfolio role | Invested, growing — untouched | Partially funding current expenses |
| Work income needed | Cover all living expenses | Cover the gap between withdrawals and expenses |
| Retirement timeline | Still targeting a future date | Semi-retired now |
At 5% real return, the Coast FIRE number at 35 (targeting $1.5M at 65) is $347,000 — nearly double the 7% estimate. Be conservative with return assumptions if you plan to stop contributing entirely.
Calculate Your Coast FIRE Number
The F.I.R.E. calculator includes Coast FIRE mode — see if you have already coasted
Open F.I.R.E. Calculator →