Balance transfer savings calculator
This UK-focused calculator compares paying your current credit card balance as-is versus switching it to a balance transfer offer. It models your current position as a single balance with a fixed APR and a fixed monthly payment. For the transfer scenario, it applies a one-off transfer fee (if any), assumes 0% interest during the promotional period, then applies a post-promo APR until the balance is cleared. You’ll see estimated payoff time, total interest, total cost, and whether the transfer looks cheaper after fees. Eligibility and real-world terms vary by provider, so use this as an initial comparison and confirm the offer details before taking any action.
- Your balance and APR stay constant, with interest compounding monthly (APR ÷ 12) outside any 0% period.
- You make the same monthly payment each month (you can set a different payment for the transfer scenario).
- The transfer fee is added to the transferred balance and repaid over time.
- No missed payments, no new spending on the card, and no promotional rate changes or early termination.
Your inputs
Compare your current card cost against a balance transfer offer with fees and a post-promo APR.
Results
- Staying put: —
- Transfer: —
- Fee model: —
Assumptions and interpretation
Balance transfers can reduce interest, but the overall cost depends on fees, how quickly you repay during the 0% period, and the rate that applies afterwards.
The “staying put” scenario assumes a fixed monthly payment on your current card at your current APR. In practice, minimum payments can change and cards can have different rates for purchases, cash advances, and promotional offers.
The transfer scenario assumes the full balance is transferred at the start, the transfer fee is added to the balance, and interest is 0% during the promotional period. After the promotion ends, any remaining balance accrues interest at the post-promo APR.
If the monthly payment is not high enough to reduce the balance after interest (once the post-promo rate applies), the calculator will tell you and won’t produce results.
Worked UK example
Example only. Results depend on your exact borrowing and lender terms.
Suppose you have a £3,500 balance at 29.9% APR and you pay £140 per month. You consider a balance transfer offer with an 18-month 0% period, a 3% transfer fee, and a post-promo APR of 24.9%. If you keep paying £140 per month, a large share of the balance may be cleared during the 0% period. If any balance remains afterwards, the post-promo APR will determine how much additional interest you pay.
The transfer can look cheaper even with a fee, especially when your current APR is high and you repay aggressively during the 0% window. But if the post-promo APR is high and the remaining balance is large, the benefit can shrink quickly.
FAQs
Common questions about balance transfers, fees, and interpreting the numbers.
Is a 0% balance transfer always cheaper?
Not always. A transfer fee, a short 0% period, or a high post-promo APR can reduce or remove the benefit. The savings depend on how quickly you repay during the promotional period.
Does the transfer fee add to the balance?
Many offers add the fee to the transferred balance. This calculator models the fee as added to the balance so you repay it over time, but always check the provider’s terms.
What if I clear the balance within the 0% period?
If you repay the full balance (including the fee) before the 0% period ends, post-promo interest does not apply. Your main cost in the transfer scenario would then be the transfer fee.
Why does the post-promo APR matter so much?
If a balance remains after the 0% period, the post-promo APR applies to that remaining amount. A high post-promo rate can quickly increase interest costs if repayment slows.
Should I change my monthly payment after transferring?
Often, increasing payments during the 0% window improves outcomes because more of your payment goes to reducing the balance rather than interest. The calculator lets you model a different payment for the transfer scenario.
Does this include the impact of new spending on the card?
No. New purchases can change interest and payment allocation rules and may not be 0%. For a clean comparison, the tool assumes no new borrowing.
Will the calculator warn me if my payment is too low?
Yes. If, once the post-promo APR applies, your monthly payment does not exceed the first month’s interest, the balance will not reduce and the tool will stop and prompt you to adjust your inputs.