Debt Consolidation Calculator
Compare your current debts against a single consolidation loan or 0% balance transfer. See how much interest you could save, check your debt-to-income ratio, and find free debt advice contacts.
Try another scenario
How to Use This Calculator
Consolidation Comparison tab
Enter up to 4 existing debts with their balances, APRs, and monthly payments. The calculator shows how long each debt takes to clear at minimum payments and the total interest you will pay. Then it compares this against a single consolidation loan at a lower APR, showing your monthly payment, total interest, and overall saving.
Balance Transfer tab
Enter your credit card balance, current APR, and the details of a 0% balance transfer offer (promotional period and transfer fee). The calculator shows the monthly payment needed to clear the balance within the 0% window and compares the total cost against staying on your current card.
Warning Signs tab
Enter your total monthly debt payments and net income to calculate your debt-to-income ratio. A traffic-light system shows whether your debt level is healthy (under 20%), concerning (20-40%), or high risk (over 40%). Free debt advice contacts are provided for anyone who needs help.
Share your result
Every input is encoded in the URL. Click Share to send your exact scenario to a partner, debt adviser, or save it for later.
The Formula
Debt consolidation savings are calculated using standard loan amortization:
Total Interest = (Monthly Payment × Months) − Original Balance
Consolidation loan payment = Principal × [r(1+r)^n] / [(1+r)^n − 1]
where r = monthly rate, n = term in months
Saving = Total Interest (current debts) − Total Interest (consolidation loan)
Debt-to-Income Ratio = Monthly Debt Payments / Monthly Net Income × 100%
The key benefit of consolidation is replacing high-APR debts with a single lower-APR loan. Credit cards at 23-30% APR generate far more interest than a personal loan at 6-10%. However, consolidation only works if you stop using the credit cards after paying them off — otherwise you end up with both the loan and new card balances.
For balance transfers, the maths is simpler: you pay no interest during the 0% period, so the only cost is the transfer fee (typically 2-4% of the balance). The saving is the interest you would have paid on your current card over the same period.
Example
Emma — 3 debts totalling £6,500
Emma has three debts: a £3,000 credit card at 23% APR, a £2,000 store card at 30% APR, and a £1,500 overdraft at 40% EAR. She is paying £190/month across all three (minimum payments).
Current situation
After consolidation (6% APR, 36 months)
By consolidating at 6% over 36 months, Emma saves £2,188 in interest and clears her debt 2 months sooner. Her monthly payment is slightly higher (£198 vs £190) but every pound goes further because far less is consumed by interest.
Important: Emma must close her credit card and store card accounts (or at least stop using them) to avoid building up new balances on top of the consolidation loan.
FAQ
StepChange — 0800 138 1111 (Mon-Fri 8am-8pm, Sat 8am-4pm). The UK's largest debt charity, offering personalised debt advice and formal solutions like DMPs and IVAs.
National Debtline — 0808 808 4000 (Mon-Fri 9am-8pm, Sat 9:30am-1pm). Free advice line run by the Money Advice Trust.
Citizens Advice — citizensadvice.org.uk. In-person and online advice covering debt, benefits, housing, and employment.
MoneyHelper — moneyhelper.org.uk. Government-backed guidance on managing debt and money. These services will never charge you or try to sell you products.