Emergency fund: how to size yours

The fridge breaks down, the car crashes, the company cuts your job. If on that day you have no money set aside, the way out is usually an overdraft, a credit card or a loan. An emergency fund is money saved so that the unexpected does not turn into debt.

The Banco Central do Brasil (Brazil’s central bank) says this directly in its Financial Education Handbook (2nd edition, 2026): keeping a reserve to cover contingencies is “an important precaution” against falling into debt. What the handbook does not do is set an amount. This article shows the criteria for arriving at yours.

What the fund covers and what it does not

The fund is for expenses you had no way of foreseeing: a health problem, an urgent repair at home or on the car, job loss or a sharp drop in income. The Investor Portal of the CVM (Brazil’s securities regulator) cites these same examples in its article Planning and managing financial reserves.

The same article excludes seasonal expenses: costs that come back every year at a known time, such as taxes and school enrollment fees. The Central Bank handbook takes the same line. It notes that many “surprises” that blow the budget are not surprises at all: they are IPTU (municipal property tax), IPVA (annual vehicle tax), school supplies and holidays that were left out of the plan.

In practice, this calls for two separate pots:

• emergency fund: only for what cannot be foreseen;
• provision for seasonal expenses: a monthly amount set aside to pay the January IPVA, the February enrollment fee and so on.

Mixing the two is the most common way to discover, on the day of the emergency, that the fund has already been spent on the predictable. How to organize the budget month by month is covered in Personal financial planning.

The starting point: the essential monthly cost

The unit of measure for the fund is not your income. It is what it costs to keep the essentials going for one month: housing, food, basic bills, transportation, health and the installments you cannot skip. Leisure, subscriptions and purchases that can be postponed are left out, because in an emergency you would cut those expenses.

An illustrative example, with round numbers:

Essential expense	Monthly amount
Rent and condo fees	R$ 1,500
Food	R$ 1,000
Electricity, water, gas, internet and mobile	R$ 400
Transportation	R$ 500
Health plan and medicines	R$ 400
Loan installment	R$ 200
Total	R$ 4,000

If this person’s income is R$ 6,000, the fund is calculated on R$ 4,000, not on R$ 6,000. Anyone who does not know how much they spend needs to start by tracking expenses for a few months; without that number, any target is a guess.

How many months to save

There is no official rule. The CVM article cites as example targets “1, 3 or 6 months of expenses” and acknowledges that it is not always possible to save several months; the minimum goal is to keep the bills paid until the problem is resolved.

Outside Brazil, the US consumer financial protection agency, the CFPB, uses a different breakdown. In a 2022 study, it groups households into those with no savings, those with less than one month of income and those with at least one month. According to the report, earlier research indicates that about one month of savings meaningfully separates those at risk of financial hardship from those at lower risk. In the same survey, 64% of respondents reported an unexpected expense in the previous 12 months, and 45% a drop in income. These are US figures, but they show that the unexpected is the rule, not the exception.

With the R$ 4,000 essential cost from the example:

Target	Amount
1 month	R$ 4,000
3 months	R$ 12,000
6 months	R$ 24,000
12 months	R$ 48,000

The choice between these ranges depends on the following criteria.

The criteria that raise or lower the target

Income stability. This is the criterion that weighs most. People with variable income, such as the self-employed, commission earners and small business owners, face weak months without warning and tend to need more months saved. For irregular income, a practical reference is to calculate the essential cost and compare it with the average of the weakest months of the past year.

Protection in case of dismissal. A formally employed worker dismissed without cause may be entitled to unemployment insurance (seguro-desemprego), a temporary financial benefit. The self-employed generally do not have this cushion and need to compensate with a larger fund.

Time to restore income. Think about how long someone with your profession and in your region realistically takes to regain equivalent income. A career with many openings calls for fewer months than a specialized, scarce role.

Dependents and household income. Children, parents who depend on you or a household with a single source of income increase the risk. Two independent incomes, in different jobs, reduce the chance that both stop at the same time.

Health and assets. People with a chronic illness, without a health plan or who depend on a car to work are more exposed to large, sudden expenses.

Insurance. The Central Bank handbook presents reserves and insurance as complementary ways of dealing with contingencies. Insurance transfers part of the risk, but has a fixed cost and only pays if the covered event occurs. The fund can be used for any emergency, but takes discipline to build and does not cover an event larger than the amount saved. If you have insurance with a deductible (the part of the loss you bear), the handbook points out that this amount needs to be in the fund.

An example of how the criteria combine: a public servant with no dependents and a health plan may find it reasonable to stay close to three months. A self-employed professional with two children and highly variable income may conclude she needs six to twelve months. Both use the same criteria; the result differs because their exposure to risk is different. These are illustrations, not recommendations.

How to get there without stalling

A R$ 24,000 target looks distant for someone who saves little each month. Ignoring returns, saving R$ 400 a month, the person in the example takes 30 months to reach R$ 12,000; with R$ 600 a month, 20 months. Returns shorten that period somewhat, but discipline matters more.

Some practices help:

• stepped targets: first one month of essential costs, then three, then the final target. The CVM examples (1, 3 or 6 months) work well as steps;
• pay yourself first: the Central Bank handbook recommends setting aside the fund’s money as soon as your salary comes in, including through an automatic monthly transfer, instead of waiting for something to be left over;
• a separate account or investment: money mixed into your everyday account tends to get spent;
• periodic review: the CVM recommends reassessing the target when expenses or income change significantly, such as after a move, a child or a new loan;
• rebuild after use: the fund exists to be used. Once you use it, resume contributing until it is restored.

There is a balance to strike. Saving everything left over, with no room for quality of life, can undermine motivation in the long run, the CVM article notes. And keeping too much money idle in a low-risk investment has a cost: it stops funding longer-term goals. Both sides go into the calculation.

Where the fund stays available

Here the rule is clear in the official sources. The Central Bank handbook recommends investing the fund in something with high liquidity and low risk, because on the day of the emergency you need the money to be there, without losses, and available quickly. Liquidity is how easily an investment can be turned into cash; the difference between liquidity and return is explained in Financial liquidity: what it means in practice.

The liquidity page of the Investor Portal makes an important caveat: high liquidity does not mean no risk. An investment can be redeemed the same day and still carry credit risk (the issuer not paying) or market risk (the price falling). So, in addition to asking “can I withdraw today?”, it is worth asking “how much do I get if I withdraw today?” and “who guarantees this money?”.

Three questions to assess any option:

1. How long until the money reaches your account? Consider weekends, holidays and redemption periods. Some investments have lock-up periods or an anniversary date before they earn interest.
2. Can the redemption value be lower than the amount invested? Bonds that are marked to market (their price updated daily to market value) can fluctuate. Details are in Tesouro Direto: bonds, rates and risks and in Fixed income and equities.
3. Who guarantees it? Deposits and some bank securities, such as savings accounts, CDBs, LCIs and LCAs, are guaranteed by the Fundo Garantidor de Créditos (FGC), Brazil’s deposit guarantee fund, up to R$ 250,000 per individual taxpayer ID (CPF) and per institution or conglomerate, with a cap of R$ 1 million every four years. Government bonds and fixed income funds do not have this guarantee; in Tesouro Direto, the Treasury’s retail bond program, the credit risk is that of the federal government.

Costs also count. For Tesouro Reserva, for example, the official page states that IOF (tax on financial transactions) applies to redemptions made within the first 30 days, and income tax follows the regressive fixed income table. Check the taxes and fees of each option, because they reduce the net amount precisely for those who need to withdraw early.

The case of floating-rate government bonds

The Investor Portal presents Tesouro Selic, a bond that tracks the Selic (Brazil’s benchmark interest rate), as suitable for an emergency fund, because its price varies little day to day (CVM, Government Bonds). The same page describes Tesouro Reserva as a bond designed for this purpose, without mark-to-market pricing and with 24-hour liquidity, and still treats it as “in a testing phase”. That information is out of date: according to the B3, Brazil’s stock exchange, the bond was launched on May 11, 2026, initially through Banco do Brasil, and the official page stated on October 8, 2026, that other institutions are planned. Check availability and terms before deciding.

Mentioning these bonds is not a recommendation: they appear here because the official sources associate them with emergency funds. Savings accounts, CDBs with daily liquidity and other options also belong in the comparison, as long as they pass the three questions above. Volatile instruments, such as shares and crypto assets, do not serve the purpose: they may be falling precisely when you need to withdraw.

Key takeaways

• Separate emergencies from seasonal expenses. The fund covers the former; the latter belongs in the budget.
• Calculate the fund on your essential monthly cost, not on your income. The number of months comes from your criteria: income stability, protection in case of dismissal, dependents, health, insurance and time to find new work.
• Start with one month and move up in steps. Review the target when your life changes and rebuild after using it.
• Where to keep it: high liquidity, low risk and a known guarantee. Ask how long until the money arrives, whether the value can be lower than what you invested and who guarantees it.