Coast FIRE is the FIRE strategy for people who want to stop the grind without stopping work: you save aggressively early, build a portfolio that will grow to your retirement number on its own, and then stop contributing. From that point, your job only needs to cover your living costs, not your future. This guide explains the maths and the mindset.

How Coast FIRE Works

The idea is simple: if you invest enough early, compound growth alone will carry your portfolio to your retirement target by your chosen age. A 30-year-old who invests $200,000 and earns 7% a year will have around $1.5 million by 65 without adding another dollar. The coast point is the portfolio size where growth alone reaches your number on time. Once you hit it, you can stop saving, take a lower-paying job you enjoy, or work part-time.

Calculating Your Coast Number

Your coast number depends on three inputs: your retirement target, your expected return, and the years until retirement. The formula is your target divided by 1.07 raised to the years remaining. A 35-year-old targeting $1 million by 65 needs about $131,000 invested today at 7% growth. Online Coast FIRE calculators do this maths instantly, but the principle matters more than the precision: the earlier you invest, the smaller the coast number.

Why Coast FIRE Appeals to So Many

Traditional FIRE demands extreme saving for a decade or more, which burns many people out. Coast FIRE asks for intense saving for a shorter period, then a normal life: you keep working, but the pressure to maximise income disappears. You can take the interesting job, the part-time role, or the career change, because your future is already funded. It is FIRE without the finish line, and for many people that is the point.

The Risks to Watch

Coast FIRE depends on investment returns, and a decade of low returns can push your number out of reach. Inflation also matters: a target set in today's dollars needs to grow with prices, so use real returns of 4-5% in your planning, not nominal 7%. Life changes like children or illness can raise your target, so revisit the number every year. Coast FIRE is a plan, not a guarantee, and it needs annual review.

From Coast FIRE to Full FIRE

Many coast FIRE followers eventually reach full FIRE anyway, because the habit of saving is hard to break and their income keeps growing. Others stay in coast mode for decades, enjoying work without financial pressure. Either outcome is a win: the coast number gives you the freedom to choose, and the choice is the reward. Start by calculating your number today, then work backwards to the monthly savings that get you there.

Coast FIRE and Career Changes

Coast FIRE is the ideal strategy for a career change: once your portfolio is on track to reach your number, you can take a lower-paying job you actually enjoy, start a business, or go back to study, without worrying about retirement. The financial pressure disappears, because the future is already funded, and the only question is whether the new work covers your living costs. Many coast FIRE followers report that the career change is the real reward, more valuable than the money itself. Calculate your coast number, then ask what work you would choose if money were not the constraint.

Key Takeaways

- Coast FIRE means investing enough early that growth alone reaches your target - A 30-year-old with $200,000 invested reaches about $1.5 million by 65 at 7% - Once you coast, work only needs to cover living costs - Use real returns of 4-5% in planning, and review the number yearly

Frequently Asked Questions

What is my Coast FIRE number? Divide your retirement target by 1.07 raised to the years until retirement. A 35-year-old targeting $1 million by 65 needs about $131,000 invested today.

Coast FIRE trades a few intense saving years for decades of freedom. Calculate your number, hit it, then choose work you actually enjoy.