What Is FIRE

FIRE stands for financial independence, retire early. The goal is to save and invest enough that your money can support your living costs. Work then becomes a choice instead of a requirement. You can stop full time work years before a normal retirement age if you want to.

FIRE has two parts. Financial independence means your savings and investments can cover your spending without a paycheck. Retire early means using that freedom to stop, or to cut back on, full time work while you are still young enough to enjoy the time. Some people stop working completely. Others keep working part time, or switch to work they enjoy more. The point is the choice.

How FIRE works

The plan is simple to state and hard to do. Spend less than you earn. Invest the gap. Keep going until the investments can pay for your life.

• Track what you spend, so you know the number you need to replace.
• Save a large share of your income, often 30 percent or more.
• Invest in low cost funds that hold many stocks and bonds.
• Let the money grow over many years. Time does much of the work.

FIRE is not a way to get rich fast. It is a way to buy time. The trade is clear. You give up some spending now to gain years of freedom later.

The math in one line

Most FIRE plans use the rule of 25. Multiply your yearly spending by 25. The result is your FIRE number. The rule comes from the 4 percent rule. If you take out 4 percent of your savings in the first year, then adjust that amount for inflation in later years, 25 times spending is the amount that supports that first withdrawal. One divided by 0.04 equals 25.

The 4 percent rule is a guide, not a promise. Bengen found in 1994 that about a 4.1 percent first year withdrawal lasted 30 years with 50 percent stocks and 50 percent intermediate term government bonds. The 1998 Trinity study tested withdrawal rates over 30 year periods. Both studies looked back at past market returns. Past returns do not set future returns. A plan that lasts 30 years may not last 50 years. A longer retirement needs a lower withdrawal rate, more savings, or some income after retirement.

Worked example: a $1,000,000 target

These are round hypothetical numbers. They are not a real household. The return used here is an assumption, not a forecast. This example uses a 7 percent annual return assumption.

• Step 1. Yearly spending is $40,000.
• Step 2. Multiply by 25. $40,000 times 25 equals $1,000,000. That is the FIRE number.
• Step 3. Check the withdrawal. 4 percent of $1,000,000 equals $40,000 in the first year.
• Step 4. Find the saving rate. Income is $80,000. Spending is $40,000. Saving is $80,000 minus $40,000, which equals $40,000 per year. That is a 50 percent saving rate.
• Step 5. Find the time. Saving $40,000 each year at an assumed 7 percent annual return grows to about $1,005,000 after 15 years. The growth factor for 15 years at 7 percent is 25.13, and $40,000 times 25.13 equals $1,005,200.

At a lower saving rate, the same target takes longer. Saving $20,000 per year at the same assumed 7 percent return takes about 21 years to reach $1,000,000. The saving rate sets the pace. The return helps, but it does not replace saving.

Financial independence is not the same as retiring

Financial independence is a money test. Your investments can cover your spending. Retiring is a life choice. You stop paid work. The two often get mixed up, but they are not the same thing.

Most people who reach financial independence keep working in some form. Work gives structure to the day. It gives social contact. It gives a sense of purpose. It can also give health coverage, which is costly to buy on your own before Medicare starts at age 65. Paid work after independence can be part time, seasonal, or project based. It can be a new field, not the old job.

Independence changes the terms of work. You can turn down a bad job. You can take a pay cut for a better schedule. You can take a year off. You can work because you want to, not because you must. For many people, that choice is the real goal. Full retirement is one option. It is not the only option.

The three main paths

Lean FIRE means retiring on a low budget, often under $40,000 a year in spending. The target is lower, so it comes sooner. The margin for error is thin. A large repair, a health bill, or a market fall can hurt.

Regular FIRE means retiring on a middle budget, often $40,000 to $100,000 a year in spending. This is the path most of the guides describe. The target is $1,000,000 to $2,500,000 at 25 times spending.

Fat FIRE means retiring on a high budget, often over $100,000 a year in spending. The target is $2,500,000 or more. The life is more comfortable, but the target takes longer to reach and costs more to hold.

Which path fits depends on your spending, your income, and how much risk you want to carry. A lower target is faster to reach. A higher target gives more room for error.

Where FIRE started

The idea grew from a 1992 book, Your Money or Your Life, by Vicki Robin and Joe Dominguez. The book asked readers to compare the hours of life they traded for money with the value they got from spending it. The idea spread through blogs and forums in the 2010s. The Mr. Money Mustache blog, started in 2011, made the case for a high saving rate and a simple life. The movement has grown since then, but the core idea has not changed. Spend less. Save the gap. Invest it. Wait.

What FIRE does not fix

FIRE does not fix a low income on its own. A high saving rate is hard when pay is low and rent is high. FIRE does not fix health costs, family needs, or a long life. It does not remove market risk. A plan built on a 7 percent return assumption can fall short if returns are lower. A plan built on low spending can fail if spending rises.

FIRE also needs a plan for the years before age 59.5, when most retirement accounts charge a 10 percent added tax on early withdrawals, and before Medicare starts at age 65. Taxable accounts, Roth IRA contributions, and other bridge funds can help. Those rules are covered in the post on retiring at 50.

Is FIRE right for you?

Ask three questions. First, how much do you spend in a year? Second, how much can you save each month without strain that you cannot keep up? Third, how many years are you willing to keep saving at that rate? The answers give you a target and a time line. If the time line is too long, you can cut spending, raise income, or accept a later date. If the target is too high, you can aim for financial independence first and full retirement later.

FIRE is a tool. It works best when the goal is clear. For some people, the goal is to stop work at 50. For others, the goal is to work on their own terms. Both count.

Education, not advice. This post explains an idea. It is not personal financial advice. Your income, taxes, health, and family needs are your own. Check the rules that apply to you before you act.

Sources

• Bengen, William P. “Determining Withdrawal Rates Using Historical Data.” Journal of Financial Planning, October 1994. Financial Planning Association
• Cooley, Philip L., Carl M. Hubbard, and Daniel T. Walz. “Retirement Savings: Choosing a Withdrawal Rate That Is Sustainable.” American Association of Individual Investors, February 1998. AAII Journal
• Investopedia. “Financial Independence, Retire Early (FIRE) Explained.” Investopedia
• Social Security Administration. “Life Expectancy Calculator.” SSA.gov