How Big Should an Emergency Fund Be? Working It Out From Your Own Bills

The question is usually asked as a number of months, and the internet answers it quickly: three months, or six, depending on who is doing the talking. Here is the quiet problem with that answer. The multiple was never the hard part. Knowing your own monthly number is the hard part, and once you have that, the multiplication takes seconds.

So before you read on, one small step: open the notes app or take a piece of paper, and write down what your household genuinely spends on essentials in a month. Not the ideal month. The real one. The rest of this article is about making that number honest, and the widget below does the arithmetic with it.

If the number surprises you, stay with it for a moment. Most people’s essentials figure is higher than their guess and lower than their total spending, and both facts matter later: the first explains why the fund feels big, and the second explains why it is smaller than you feared.

What the fund is for

MoneySmart, the ASIC consumer site, defines the fund plainly: money you save to cover urgent or unexpected costs, such as car repairs, unexpected travel or an urgent medical bill. Those three examples are the ones to hold on to, because they share a shape. They are all things that arrive without warning, need money quickly, and cannot wait for a pay cycle.

A small problem that grows expensive is the fund’s native territory, and the site’s piece on the plumbing problems that start small and get expensive is the same pattern in the home: the cheap moment to act is early. The fund and the small repair are the same lesson at two different speeds.

That shape is also the best test for what the fund is not for. A holiday is not an emergency. A sale is not an emergency. A bill you knew was coming, like registration or a school term, is a planned expense, and it belongs in a different bucket. The fund has one job: to absorb the things nobody planned for, so they do not turn into debt. The three examples also share a timing, which is the pressure the fund removes: each one needs money before the next pay arrives, and a cost that can wait a fortnight is a cost the weekly budget can absorb.

The method, in the source’s own words

MoneySmart’s method is one sentence, and it is quoted here rather than paraphrased: work out your monthly expenses, then multiply this by the number of months you would like to cover. That total can be your savings goal.

A worked example makes the shape concrete. These are made-up figures, chosen to be round, and they are not a suggestion about your own. Suppose your monthly essentials come to $2,400 and you decide to cover three months. The target is $7,200. At $50 a week, that target takes 144 weeks, which is a little under three years. The sums are the easy part; the two numbers going in are the ones that need care.

The same multiplication answers the other common question, about six months rather than three. At $2,400 a month, six months is $14,400, which is where the six-month recommendations come from: the same two inputs, a different choice in the middle. Nothing about the method changes when the number of months changes, which is why the widget asks for both rather than deciding for you.

The widget above does the same multiplication with your own figures, and it shows the inputs back to you so you can see the arithmetic rather than a magic number. That visibility is deliberate, because the multiplication is the part people try to skip, and skipping it is why a fund so often stays a slogan. Three months of a number you have not written down is not a target; it is a mood. The widget refuses the mood, because it needs the number first.

That is also the way to use the widget well: it is only as good as its two inputs. If the monthly figure is a guess, the target is a guess with a dollar sign on it, and the weeks-to-go figure inherits the same wobble. This article spends its length on the inputs for that reason, and the multiplication can look after itself.

The first number, found carefully

The monthly figure is where self-deception lives, and it deserves care. Start with the regular bills: rent or mortgage, power, water, phone, insurance, transport, childcare. Then add the weekly costs that never feel like a bill but always are: groceries, fuel, the chemist, the pet food. Then find the annual expenses, like registration or a yearly policy, and divide each by twelve, because they are part of a month even when they are not in every month.

The part that matters is what you leave out. Discretionary spending, takeaway, the subscriptions you are not sure about: those do not belong in the emergency number, and saying that out loud matters. The fund covers essentials, not lifestyle. If building the figure proves hard, MoneySmart points readers at a budget planner, and that is a perfectly good place to start; the same discipline of running the numbers instead of guessing is what the site’s guide to tax planning through the year applies to a different deadline.

One practical tip for the annual expenses: gather them from the last twelve months of statements rather than from memory. Memory arranges the year the way it felt; statements arrange it the way it happened.

The two hardest lines in the figure are the annual expenses and the weekly ones, and they are hard for opposite reasons. The annual bills are easy to forget precisely because they are rare, which is why dividing them by twelve belongs on paper. The weekly costs are easy to under-count because they are frequent, and small, and paid without ceremony; the groceries, the fuel and the chemist are the lines that quietly decide whether the monthly figure is honest.

A number that is too high is its own kind of failure, because the fund looks impossible and never gets started. A number that is realistic is a number you can make progress against.

The pace, and the patience

MoneySmart offers an arithmetic that belongs on the fridge: $20 a week into a savings account is over $1,000 in a year’s time. The point of the line is not the $1,000. It is that small, regular amounts build a buffer, and the buffer is the thing that changes how a bad week feels.

The limit deserves stating plainly too. At $20 a week, a full fund takes years, which is why the fund is built in the background rather than by willpower. An automatic transfer does the work once it is set up, and the amount can rise when a pay rise arrives. Nobody is asked to be heroic about this. They are asked to be regular. The pace is not competing with this month’s budget either; the fund runs alongside the budget rather than against it, and the transfer is what keeps it running when the month is busy.

The weekly amount is also the dial that makes the plan survive. A transfer that is too ambitious gets cancelled in a tight month, and a cancelled transfer is worse than a small one, because it breaks the habit along with the plan. Setting the amount at a level the household will not miss is not a failure of ambition; it is the reason the rest of the arithmetic gets a chance to run.

Where it lives

The source’s first practical step is a sentence with a whole mechanism inside it: use a separate savings account. The separation is not tidiness. It is the design. Money in the everyday account is available to the week, and the week always has a use for it. Money in a separate account has to be fetched deliberately, which is exactly the friction the fund needs.

The reader’s other question deserves a plain answer too: yes, the fund and ordinary savings can coexist. Ordinary savings pay for the planned things, like the holiday and the new washing machine. The emergency fund covers the unplanned, and it keeps its one job. Two accounts, two purposes, and the emergency account is the one you do not raid for a sale. Separation also answers the question of whether the money should be visible. It can be visible; it simply should not be spendable by reflex, and an account that requires a deliberate transfer is exactly that.

One more thing about what separation is not. It is not a lock, and it is not a judgement about willpower; the fund is meant to be reachable in the week it is needed. The separation is a speed bump, and a speed bump is all it needs to be: enough friction that the money is fetched on purpose rather than spent on the way past.

When life is bigger than the fund

One line from MoneySmart belongs here, stated as the source states it and not stretched beyond that: insurance is the complementary protection for a reader who cannot work. That is the whole of the sourced position on the subject, and this article stops where it stops, because comparing products is a different job with different rules.

The same restraint applies to the other fixed costs that compete with a fund. A repayment on a car loan, for example, is part of the monthly picture, and it competes directly with the transfer you are trying to protect. That is a decision for the household’s own numbers, and this article does not make it for you.

The number, and the account

The five-minute version of this article is four steps. Write your monthly essentials figure down, honestly. Run it through the widget above, or multiply it on paper if you prefer, and choose the number of months you are aiming to cover. Open a separate savings account, if you do not already have one. Then set one automatic transfer, small enough that it will not be cancelled in a hard week.

The three-month target is MoneySmart’s starting point, and it is a good one, but the number that matters is the one your own bills produce. Start where you are, build it in the background, and let the fund do the one job it was made for. And one last thing, because it is the part that makes the number real: write the target down where you will see it, next to the account. A target that lives in a notes app is a target; a target that lives beside the transfer is a plan.

Sources: MoneySmart – Save for an emergency fund