The FIRE Movement Guide: Achieving Financial Independence and Early Retirement
FIRE — Financial Independence, Retire Early — is less about quitting work than about making work optional. The arithmetic is simple: build a portfolio large enough that its returns cover your living costs indefinitely.
What is the 4% Rule and How Do You Calculate Your FIRE Number?
The 4% rule comes from William Bengen's 1994 research and the Trinity Study: a portfolio of stocks and bonds could sustain an initial withdrawal of 4% of its starting value, adjusted upward for inflation each year, for at least 30 years across every historical period tested.
FIRE Number = Annual Expenses × 25
| Annual spending | 4% rule (25×) | 3.5% rule (28.6×) | 3% rule (33×) |
|---|---|---|---|
| $40,000 | $1,000,000 | $1,143,000 | $1,333,000 |
| $60,000 | $1,500,000 | $1,714,000 | $2,000,000 |
| $100,000 | $2,500,000 | $2,857,000 | $3,333,000 |
Note what this makes obvious: every $100/month of recurring spending you remove cuts $30,000 from your target. Reducing expenses shortens the timeline from both ends — a lower target and a higher savings rate.
Lean FIRE vs. Fat FIRE vs. Coast FIRE: Choosing Your Path
| Path | Annual spending | Typical target | Who it suits |
|---|---|---|---|
| Lean FIRE | Under ~$40,000 | $500k - $1M | Minimalists, low cost-of-living areas, no dependents |
| Regular FIRE | $40,000 - $100,000 | $1M - $2.5M | Middle-class lifestyle maintained without employment |
| Fat FIRE | $100,000+ | $2.5M - $5M+ | High earners unwilling to trim travel, housing, private schooling |
| Coast FIRE | Any | Enough invested today to grow into the target by 65 | Those who want to stop saving, not stop working |
| Barista FIRE | Any | Portfolio covers most costs | Part-time work bridges the gap and supplies health coverage |
Coast FIRE in practice
A 30-year-old with $180,000 invested at a 7% real return reaches roughly $1.4 million by 65 without adding another dollar. They have already coasted; every further contribution simply buys an earlier finish line.
Protecting Your Portfolio Against Sequence of Returns Risk
Sequence of returns risk is the danger of a severe bear market in the first few years of retirement. Selling depressed assets to fund living costs permanently removes shares that would have participated in the recovery — two retirees with identical average returns can end up with wildly different outcomes purely because of order.
- Cash buffer: hold 1-2 years of expenses in an HYSA or T-bills and spend from it instead of selling during a drawdown.
- Bond ladder: stagger 5-10 years of Treasuries or TIPS maturing annually, creating a guaranteed income floor through any downturn.
- Rising equity glidepath: start retirement near 60% stocks and increase equity exposure over the first decade, when the risk is highest.
- Variable withdrawals: guardrail rules — trim spending 10% after a year the portfolio falls, raise it after strong years — historically support withdrawal rates above 4.5% at similar failure risk.
- Flexible income: even $10,000-15,000 of part-time earnings in the first few years dramatically improves long-run success rates.