Free UK Debt Calculators

Which debt calculator should I use?

• Several debts and want quick wins? Use the debt snowball calculator.
• Several debts and want to pay the least interest? Use the debt avalanche calculator.
• Can't decide between the two? The snowball vs avalanche calculator runs both on the same debts.
• Just one loan, card or overdraft? The UK debt calculator gives you a single debt-free date; the debt repayment calculator handles several at once.
• Can't afford your minimum payments? Estimate a plan with the debt management plan calculator, then get free advice from StepChange or National Debtline.
• Thinking about a consolidation loan or 0% card? Check the consolidation calculator or the balance transfer calculator first.
• Don't know what you can afford? Start with the budget builder.

Which debt payoff method should you use?

The debt snowball clears your smallest balance first for motivating quick wins, while the debt avalanche clears your highest interest rate first to pay the least total interest. The snowball keeps more people motivated; the avalanche saves the most money. Both work by paying every minimum and directing spare cash at one debt at a time.

Not sure which fits you? Read the snowball vs avalanche guide, or run both at once in the snowball vs avalanche calculator — enter your debts once and see both debt-free dates and total interest side by side in minutes.

What you need before you start

For each debt you need four things: the outstanding balance, the interest rate as an APR, the minimum payment, and the name of the creditor so you can tell them apart. Then one figure for yourself — the extra amount you can add on top of the minimums each month.

All four per-debt numbers are on your monthly statement. The balance and minimum payment are usually near the top; the APR is either alongside them or in your credit agreement. If a card sets its minimum as the higher of a fixed amount and a percentage of the balance — which most UK cards do — enter both, and the calculator will recalculate it each month as the balance falls.

Include every unsecured debt: credit cards, store cards, overdrafts, personal loans, car finance and buy-now-pay-later. Leave out your mortgage and any priority bills such as council tax, rent or mortgage arrears, energy, court fines and money owed to HMRC. Those are paid in full first and sit outside a payoff plan entirely — see the mortgage calculators for secured-debt decisions.

If you do not yet know your overpayment figure, work it out before you run anything. The budgeting calculators exist for exactly that, and a plan built on a number you cannot sustain is worse than no plan at all.

How to read your results

Both calculators return the same four outputs:

• Your debt-free date — the month the last balance hits zero, assuming you keep the overpayment going.
• Total interest paid — the real cost of the plan, and the number to compare between the two methods.
• Your payoff order — which debt gets the spare cash first, second and third.
• A month-by-month schedule — what to pay each creditor each month, which is the part you actually follow.

The comparison worth making is total interest against how the order feels. Run the snowball, note both numbers, then run the avalanche with identical inputs. If the interest difference is small — and across a typical UK debt mix it often is — the method you will still be following in a year's time is the better one, whatever the maths says.

What these calculators assume

Every projection holds your interest rates constant, adds no new borrowing, and ignores fees and charges. Those assumptions are what make a clean forecast possible, and they are also where a real payoff plan drifts from the model.

Specifically, both tools apply interest monthly at the APR you enter divided by twelve, then apply your payments. Percentage-based minimums are recalculated from the falling balance each month. Beyond that:

• Rates are held flat for the whole projection. A promotional 0% period ending, or a variable rate moving, is not modelled — re-run the numbers when either happens.
• No new spending is added. Putting fresh purchases on a card you are trying to clear invalidates the forecast faster than anything else.
• Fees, charges and missed-payment penalties are not included. Neither is a payment holiday.
• A minimum payment smaller than the monthly interest never clears the debt. If that is where you are, no ordering strategy fixes it, and free regulated advice is the right next step — StepChange, National Debtline and Citizens Advice all help at no cost.

Treat the debt-free date as a projection you refresh, not a promise. Re-running it every few months, and after any rate change, keeps it useful.

Frequently asked questions