An emergency fund is the money you deliberately do not invest. It pays for the broken furnace, the car repair and the months when no money comes in. Without it, your portfolio has to step in when something goes wrong. Then you sell at whatever price applies that day, even if it is low. That is why the emergency fund comes before your first investment plan.
The rule of thumb: 3 to 6 months of expenses
FINRA, which oversees US brokers, names three to six months of living expenses and adds that people with variable income may need a larger reserve. The FDIC, the US deposit insurer, also names three to six months of expenses and ties the amount to your income, your expenses and the number of people in your household. In another article, it writes that financial experts generally recommend at least six months of living expenses in a federally insured product.
Many people are not there yet. In the Federal Reserve survey for 2025, 55% of adults said they had set aside money for three months of expenses.
I count in months of expenses, not months of income. Your income says nothing about what you have to pay in an emergency. If you earn $4,000 after tax and spend $2,500, three months cost you $7,500, not $12,000. If you still prefer to count in income, use your take-home pay, because that is what you live on.
Monthly expenses include rent or mortgage, utilities, insurance, groceries, transportation, children and ongoing contracts. They do not include your savings rate or your next vacation. The most accurate number comes from adding up twelve months of bank statements and dividing by twelve. That way the annual insurance premiums and other once-a-year bills are included.
How large the fund should be for your situation
The rule of thumb is a range. Where you land in it depends on who catches you when your income stops.
| Situation | Rule of thumb | At $2,500 of monthly expenses |
|---|---|---|
| Employee, no children or two incomes | 3 months of expenses | $7,500 |
| Family with one main earner | 6 months of expenses | $15,000 |
| Self-employed or business owner | at least 6 months of expenses | $15,000 and more |
| Retired with a regular pension | 3 months of expenses | $7,500 |
Employees
Depending on where you live, employees often have two safety nets: sick pay and unemployment benefits. In the US, each state runs its own unemployment insurance program within federal guidelines. How much these benefits replace and for how long depends on your state or country. The emergency fund covers whatever they do not replace, plus the bills that arrive at exactly that moment. That is why I use 3 months of expenses here.
Families
With every person in the household, the expenses you cannot cut grow. If the only income or the larger one stops, it hits everyone at once. If you own a home, you also pay for every repair yourself. Here I use 6 months of expenses, the upper end of the rule of thumb.
Self-employed and business owners
Your safety nets are missing unless you set them up yourself. No employer keeps paying you when you are sick. And according to CareerOneStop, the job portal sponsored by the US Department of Labor, most self-employed workers, independent contractors and freelancers are not eligible for unemployment benefits. On top of that, your income goes up and down. That is why I use at least 6 months of expenses. If a single client brings a large share of your revenue, plan for more.
As a business owner, you need three separate pots:
- The personal emergency fund for your personal monthly expenses.
- A cash reserve inside the business for its fixed costs.
- The tax reserve. If you pay income tax in installments during the year, that money belongs to the tax office and never counts as emergency money. How and when you pay depends on the country you live in.
Retirement
Your pension arrives every month, and losing a job is no longer a risk. The emergency fund then covers repairs, replacements and health costs. For that I use 3 months of expenses. If you also live off a portfolio, you need a second, separate buffer for your withdrawals. I worked out what that buffer achieves in Retirement withdrawal plan.
Where to keep your emergency fund
The emergency fund belongs in its own savings account. FINRA describes the right place as a liquid, interest-bearing account you can withdraw from at any time without penalty, such as a savings account at a bank or credit union. For alternatives like certificates of deposit or money market funds, it tells you to check how quickly you can get your money and which fees or penalties apply. A checking account is not a good fit either, because the emergency fund mixes with your everyday money there and quietly shrinks.
Deposit insurance matters. In the US, FDIC insurance covers $250,000 per depositor, per FDIC-insured bank, for each account ownership category. Deposits in the same category at the same bank are added together. Stocks, bonds and mutual funds are not covered, even when an insured bank sells them. An emergency fund the size of the examples here sits far below the limit. Outside the US, coverage depends on your country’s deposit insurance, so check the rules where you live.
Interest on your emergency fund is usually taxable income. How it is taxed depends on the country you live in.
Why the emergency fund does not belong in stocks
Stocks go up and down. That alone would not be a problem if emergencies only came in good market years. But they come when they want. In a contraction, demand and investment fall, companies cut production and hire less. I describe how these stages unfold in The business cycle. If you need money right then and only have it in your portfolio, you sell at today’s price, however low it is. You cannot make up that loss later, because the units you sold are gone.
A fully worked example
I take two self-employed people, A and B. Both have $2,500 of personal monthly expenses and save $1,000 a month.
A builds the emergency fund first: 6 times $2,500 is $15,000. At $1,000 a month, that takes 15 months. After that, the $1,000 goes into an investment plan. After another 15 months, A has $15,000 in the savings account and $15,000 in the portfolio.
B invests everything from the first month. After 30 months, the portfolio holds $30,000.
Now prices fall by 30%. At the same time, three months of income are missing, a gap of $7,500. To keep the effect visible, I leave out taxes, costs and interest and assume that all units were bought at the same price.
A pays the $7,500 from the savings account. $7,500 remains there. The portfolio stands at $10,500 and stays untouched.
B has to sell. The portfolio stands at $21,000. B sells $7,500, which is 35.7% of the units. $13,500 remains.
Assume that prices later return to their old level. Then A’s portfolio is back at $15,000, and together with the savings account A has $22,500. For B, the $13,500 grows to $13,500 divided by 0.7, which is $19,285.71. A is ahead by $3,214.29. The units B sold at the low would be worth $10,714.29 after the recovery. B received $7,500 for them. The difference of $3,214.29 is the loss the sale locked in.
The counter-calculation belongs here too. If prices stay where they were, both have $22,500. If prices rise without a setback, B is ahead, because more money was invested. The emergency fund costs return in good times. In exchange, you do not have to sell in bad times, as long as it lasts.
The order: emergency fund first, then invest
- Expensive debt first. An overdraft, a credit card balance or a personal loan costs interest. Every dollar you pay off saves that interest with certainty. Why debt is a safe comparison return is covered in How to invest $20,000.
- Build the emergency fund in its own savings account. With a target of $7,500 and $500 a month, that takes 15 months.
- After that, put your full monthly savings into an investment plan. What it can add up to over the years and what costs take away, you can work out in the ETF savings plan calculator. The compound interest calculator shows how a sum grows with different returns.
- If you use the emergency fund, refill it first. During that time, your monthly savings go back into the savings account.
- Check the amount once a year. A child, the step into self-employment or retirement changes your rule of thumb.
Money for expenses you already know about, such as a new car in two years, is not emergency money. It gets its own pot next to the emergency fund. Everything beyond that can work for the long term.