A balance transfer moves debt from a high-interest credit card to a new card with a low or 0% introductory APR. It can save hundreds or thousands of dollars — but there is a fee up front, the intro rate expires, and whatever is left afterward is charged the card’s regular rate. This calculator runs both paths month by month with the same payment so you can see whether the transfer actually pays.
How to use the balance transfer calculator
- Enter the balance you plan to move and your current APR.
- Enter the monthly payment you will make — the same amount is used for both options.
- Enter the offer: transfer fee (percent and any minimum), intro APR, intro period in months, and the APR after the intro period.
- Read the savings on the tape, then compare payoff times, the balance chart and the side-by-side table.
How the comparison is calculated
Each month on either card:
On the new card the APR is the intro rate for the intro months and the regular rate afterward. The savings figure compares total interest on the current card with interest plus the fee on the new one.
Worked example
You owe $8,000 at 24.99% and pay $300 a month. An offer gives 0% for 18 months with a 3% fee, then 21.99%.
Keep the current card: 40 months to pay off, $3,796.69 of interest.
Transfer: fee = 3% × 8,000 = $240, so the new balance is $8,240. After 18 interest-free payments, $2,840 remains and is charged 21.99%. Paid off in 29 months with $308.31 of interest — $548.31 including the fee.
Savings: $3,248.38, and you are debt-free 11 months sooner.
Raising the payment to $457.78 would clear the full $8,240 within the 18 interest-free months, leaving the fee as the only cost.
When a transfer does not pay
The payment is too small
If most of the balance will still be there when the intro rate ends, the go-to APR takes over and the savings shrink. Aim to clear the balance within the intro period.
The fee is large relative to the interest saved
A 5% fee on a short 6-month intro period may save little if you could pay the debt off quickly anyway. Enter the actual offer to check.
You keep spending
New charges on the old card recreate the debt, and purchases on the new card may carry the regular rate from day one. Many people put the old card away while the transfer is paid down.
Alternatives to compare
A fixed-rate personal loan offers a set payoff date and no expiring promo, which suits larger balances that cannot be cleared in 12 to 21 months. Use the credit card payoff calculator to model paying the card down directly, or the APR calculator to compare a consolidation loan’s fees and rate.
Estimates only. Card issuers calculate interest on daily balances, may apply penalty rates after a late payment, and set their own fee and payment-allocation rules.
Frequently asked questions
Is a balance transfer worth it?
It usually is when the interest you avoid during the intro period is larger than the transfer fee, and you can pay off most of the balance before the intro rate ends. Moving $8,000 from a 24.99% card to a 0% card for 18 months with a 3% fee saves about $3,250 if you pay $300 a month.
How is the balance transfer fee calculated?
Most cards charge 3% to 5% of the amount transferred, often with a minimum such as $5 or $10. The fee is added to your new balance on day one, so $8,000 at 3% becomes $8,240.
What happens when the intro APR ends?
Any remaining balance starts accruing interest at the card's regular rate, often 20% or more. To avoid that, divide the new balance by the number of intro months and pay at least that much — $457.78 a month in the example.
Can I still use the old card?
You can, but new purchases on either card make the plan harder. On the new card, purchases may not get the intro rate, and under the CARD Act payments above the minimum go to the highest-rate balance first, so new purchases are paid down before the 0% transferred balance.
Does a balance transfer hurt my credit score?
Applying for a new card triggers a hard inquiry and lowers the average age of your accounts, which can dip your score briefly. Paying the debt down lowers your credit utilization, which tends to help over time.