Start with take-home income
Use income after tax and other deductions. For example, if your monthly pay before deductions is £2,800 but £2,300 reaches your bank account, start your budget with £2,300. Include other reliable household income once, and avoid counting transfers between your own accounts as income.
List expenses without double counting
Gather a month of bank statements and receipts. Group spending into housing and utilities, food, transport, debt payments, and other expenses. If a credit card payment covers purchases you already included in those categories, counting both the purchases and that payment can overstate spending. Separate repayment of older debt from current purchases.
Give savings a place in the plan
Enter the amount you intend to save as its own figure. A budget can show money left after bills but still leave too little for a planned goal. Putting the savings amount into the calculation makes that tradeoff visible.
A worked example
Suppose take-home income is £2,300. Housing and utilities cost £900, food £350, transport £150, debt payments £100, and other expenses £250. Total expenses are £1,750. With planned savings of £300, the remaining amount is £250: £2,300 − £1,750 − £300.
Use the result to make an adjustment
A positive balance is money not yet allocated. A zero balance means the full amount is allocated. A negative balance shows a shortfall in the plan. Check missing expenses and input mistakes first, then compare scenarios by changing amounts that you can realistically adjust.
Review what actually happened
At the end of the month, compare your plan with actual spending. One expensive month does not necessarily represent every month. Update the next budget using what you learned, especially if bills, income, or household needs changed.
Try the calculator · Browse all guides
Written by Iftekhar Arshad · Published 4 October 2026. Educational examples; figures are illustrative and are not personalised financial advice.