50/30/20 Budget Calculator United Kingdom

What the 50 30 20 budget calculator does

The calculator divides your monthly take-home pay into three buckets: needs, wants and savings. Instead of guessing what you can afford to spend or save, you get three target figures based on one of the most widely used ways to structure a budget.

Detailed budgets that track dozens of categories work well but are easy to abandon; three broad buckets are simple enough to keep up. The calculator shows what a balanced month looks like on your income, so you can see how close your current spending is to that shape.

How the 50/30/20 rule works

Half of your take-home pay, 50%, goes on needs. Just under a third, 30%, is for wants. The remaining fifth, 20%, goes to savings or clearing debt faster than the minimum. On £2,500 a month, that is £1,250 for needs, £750 for wants and £500 for savings.

Giving savings its own fixed share means it is planned before lifestyle spending grows to fill whatever is left. Keeping essential and discretionary spending in separate buckets also makes it obvious when one is crowding out the others.

Needs, wants and savings explained

Needs are the essentials you would struggle to go without: housing, utility bills, groceries, transport to work, insurance and minimum debt repayments. If missing a payment would cause a real problem, it usually belongs here.

Wants make life enjoyable but are a choice: eating out, streaming subscriptions, hobbies, holidays and upgrades you could live without. The line between needs and wants is not always sharp, and drawing it honestly is part of the value of the exercise.

Savings covers building an emergency fund, paying into a pension or investments, and paying off debt faster than the minimum.

Using take-home pay, not gross

The rule divides your take-home pay, what is left after Income Tax and National Insurance. Using gross salary would overstate every bucket, because a large part of gross pay never reaches your account.

If your income varies because of overtime, commission or irregular hours, use a typical or slightly cautious month so the budget holds up when earnings dip. Couples who share finances can add their take-home pay together and split the total, since household bills are usually paid jointly.

What you need to enter

• Your monthly take-home pay.

Enter the amount that reaches your account after deductions, and the tool multiplies it by each share of the rule. If your pay changes, enter the new figure.

Reading your result

The output shows how much to allocate to needs, wants and savings, adding up to your full take-home pay.

Compare the targets with what you actually spend. If your needs already exceed the needs figure, your fixed costs are high for your income, which is common where rent or a mortgage takes a large share. If your wants overshoot, there is usually room to move some of that spending to savings. The gap between the target and your real spending is often more useful than hitting the percentages exactly.

When to use this tool

• To build a simple monthly budget from scratch.
• To check whether your spending is broadly balanced.
• To set a savings target from your income.
• To talk through household finances with an easy, shared framework.

Adapting the rule to your life

No single split fits everyone. Someone renting in an expensive city may find needs regularly take more than half their income, which is a reason to keep wants lean and protect savings rather than give up on budgeting. Someone with low fixed costs might comfortably save well over a fifth of their pay and reach a goal faster.

Within the savings bucket, order matters. A small emergency fund usually comes first, because it stops an unexpected bill turning into debt. Then clearing high-interest debt tends to beat saving, since the interest you avoid is often higher than the interest you would earn. After that, longer-term saving and investing through a pension or an ISA can take over. Use the calculator to set the size of the savings bucket, then decide where each pound in it should go.

Revisit the split after a pay rise, a house move, the end of a debt or the start of a new goal, since each changes what a sensible balance looks like.

This is general information only and not financial advice.

About This 50 30 20 Budget Calculator

Use this 50 30 20 budget calculator to get an instant, accurate estimate. The figures follow official GOV.UK guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.