Mortgages & Money2 min check

Debt Repayment Calculator

Estimate how long until your debt is cleared and how much interest you'll pay at your current monthly payment.

Short answer

Months to clear = -log(1 − (balance × monthly rate) ÷ payment) ÷ log(1 + monthly rate). Paying just the minimum on a credit card can take 20+ years. Adding even £50/month can cut years off and save thousands in interest.

Step 1 of 10%

Calculation method, coverage and version

Inputs used: Current balance, APR / interest rate, Monthly payment.
Calculation approach: The calculator applies the rules and assumptions described in “How it works” to the values you enter. Rounding can cause small differences from an official or provider calculation.
Coverage: Mortgages & Money. UK nations, tax treatment, local rules and provider criteria can differ; check the official sources shown below before acting.
Content version: No page-specific review date is currently published. Treat the result as indicative and verify current rules independently.

Not included unless explicitly requested: personal circumstances not entered, provider discretion, future rule changes, professional fees and case-specific exceptions. Read the full calculator methodology.

Primary sources and official verification

Use these official sources to verify current rules before acting. Coverage and dates can differ across England, Scotland, Wales and Northern Ireland.

See the sitewide source policy.

How it works

Each month, interest is charged on the remaining balance, then your payment reduces what's left. The higher your payment relative to the interest, the faster the balance falls. We solve the standard amortisation formula for time.

Worked example

£3,000 credit card balance at 22% APR, paying £100/month: 41 months to clear, £1,100 interest. At £150/month: 24 months, £590 interest — saves £510 and 17 months.

Who should use this

•Anyone with credit card or overdraft debt
•People comparing snowball vs avalanche payoff strategies
•Households planning a fixed monthly repayment

Common mistakes

×Paying only the minimum (designed to maximise lender interest)
×Not transferring to a 0% balance transfer card if eligible
×Adding new spending to a card you're trying to pay off
×Ignoring free debt advice from StepChange, Citizens Advice or National Debtline

Frequently asked questions

Snowball or avalanche method?▾

Avalanche (highest rate first) saves the most money. Snowball (smallest balance first) gives quick wins for motivation. Both work — pick what you'll stick to.

Should I use savings to clear debt?▾

Usually yes if debt rate exceeds savings rate. Keep a £1,000 emergency fund first to avoid going back into debt.

Will paying off debt hurt my credit score?▾

No — clearing balances improves your credit utilisation ratio and score. Don't close old cards immediately though.

Related calculators

Credit Card Payoff →Debt Consolidation →Emergency Fund →Household Budget →