A sinking fund is money you set aside monthly for a known, irregular expense so that it never lands as a shock. In Budget Fury each fund is a goal with a target and a date; the app divides the target by the months remaining and reserves that amount inside the monthly budget, before spending money is allocated.
The problem sinking funds solve
Look at a year of your bank statements and you will find that the months you consider "bad" are almost never months where your day-to-day spending was unusual. They are months where something predictable but infrequent arrived: the insurance renewal, the MOT, Christmas, a birthday cluster, the dentist, the annual software bill.
None of these are emergencies. You know they are coming. But because they do not appear in a monthly budget, you keep meeting them out of that month's spending money — which means either overspending or raiding savings. Both feel like failure, and neither is: the budget was simply built on a twelve-month lie, that every month costs the same.
A sinking fund corrects the lie. You take the annual cost, divide by twelve, and treat it as a monthly expense. The insurance bill still arrives in March; it just arrives against money that has been quietly accumulating since April.
Which expenses deserve a sinking fund
The test is simple: predictable, non-monthly, and large enough to hurt. If it meets all three, it needs a fund. A common starting list:
- Car — insurance, service, tyres, road tax. Usually the biggest.
- Christmas and gifts — the classic. Twelve months of small contributions instead of one January of regret.
- Home maintenance — boiler service, repairs, the thing that will break this year even if you don't know which thing.
- Annual subscriptions and insurance — anything billed yearly.
- Health — dentist, optician, excess payments.
- Travel — the holiday, and the flights home for the wedding.
- Replacements — phone, laptop, washing machine. These have a known lifespan; treating them as surprises is a choice.
Do not start with all seven. Start with the two that caused the worst month last year. A sinking fund only helps if you keep funding it, and three funds you sustain beat eight you abandon in month two.
Sinking funds vs. an emergency fund
People conflate these and then wonder why their emergency fund never grows.
An emergency fund is for the genuinely unforeseeable: job loss, an urgent repair with no warning, a medical event. It has no target date and it should be hard to reach.
A sinking fund is for the entirely foreseeable. It has a date and a known amount, and spending it is success, not failure.
The reason this distinction is worth enforcing: if car insurance comes out of your emergency fund, your emergency fund is permanently between $0 and "about to be raided", and you will conclude you are bad at saving. You are not. You are using one account for two jobs.
How much to put in each month
The arithmetic is deliberately trivial: target ÷ months until you need it. A $900 insurance renewal eleven months away is $82 a month.
Two adjustments worth making. First, if you are starting mid-cycle and the monthly figure is uncomfortable, fund it to a partial target this cycle and to the full amount from next renewal — a fund that covers 60% of the bill is enormously better than one you never started. Second, for maintenance-type funds where there is no fixed amount, use last year's actual spend as the target; it is a better estimate than your instinct.
The total across all your funds is the number that matters. If it exceeds what is left after fixed expenses, you do not have a savings problem — you have a plan that does not fit your income, and the funds are the first place it becomes visible.
Set up a sinking fund in Budget Fury
- List what wrecked a month last year
Scroll back through twelve months and find the irregular expenses. Write down the amount and the month each one landed. This list is your fund list.
- Create a goal for each fund
Open the Goals tab and tap + Add goal. Give it a name you will recognise (“Car insurance 2027”, not “Savings 2”), the target amount, and the date you need it by. Add a photo if it helps — goals you can picture get funded.
- Let the app do the division
Budget Fury works out the monthly contribution from the target and the date, and shows the months remaining on the goal row so you can see at a glance whether you are on track.
- Check it appears in the monthly budget
Back on the Budget tab, the total of your funds appears under Goals savings, reducing what is available for envelopes. This is the part that makes it real: the money is committed before you can spend it.
- Look at the year, not just the month
Switch to Year Forecast. Because goals and recurring expenses are both projected forward, you can see which months are tight once every fund is being paid into — and adjust now rather than in November.
- Spend the fund when the bill arrives, guilt-free
When the renewal lands, record it against the goal. The fund empties, which is what it was for. Then set the next one, with twelve months to fill it instead of one.
Common questions
How many sinking funds should I have?
Two or three to start, growing to five or six as they become habit. The constraint is not the app; it is whether your income covers the total monthly contribution alongside your fixed expenses and a sane spending allowance.
Do I need a separate bank account for each fund?
No. Most people keep one savings account holding the combined balance and let the app track what each fund is owed. Separate accounts add admin without adding discipline — the discipline comes from the fund being visible in the budget.
What if I need the money for something else?
Then take it, deliberately, and reset the goal's date. The value of the system is not that it locks money away — it is that you see exactly what raiding the fund costs you in months. That is usually enough to make the decision honestly.
Is a sinking fund the same as a savings goal?
Mechanically, yes, and Budget Fury treats them identically — target, date, monthly contribution. The difference is intent: a savings goal is something you want, a sinking fund is something you will owe. Both benefit from being funded before spending money is allocated.
Funds that come out of the budget, not out of hope
In Budget Fury a sinking fund is a goal, and goals take their cut at the top of the month — the same way rent does. Free on iPhone, iPad and Mac.