Credit card offer check
Balance Transfer Calculator
Last updated: October 2026
A 0% balance transfer offer sounds free, but it usually carries a fee, it ends on a fixed date, and whatever you still owe then goes back to a regular rate. This calculator runs your balance through both paths with the same monthly payment: keep it on the current card, or move it.
It also shows how much would be left when the promotion ends and the exact payment that clears the balance before then, which is the number that decides whether the offer works.
Inputs
Your balance, the offer terms, your payment.
Calculating the default example.
The fee buys time, not forgiveness
A transfer fee is a one-time charge, usually added to the balance you move. In return, the promotional months charge little or no interest, so more of each payment reduces the debt. The offer pays off when the interest you avoid is larger than the fee plus any interest after the promotion.
The second and third results matter most. If something is still owed when the promotion ends, it starts costing interest again. Paying the amount in the third result each month clears the balance before that happens.
Offer checks
The calculator assumes no new purchases on either card and on-time payments every month.
Stay or move, same payment
Both rows use your monthly payment. Total cost is interest for the current card, and fee plus interest for the transfer.
| Option | Fee | Payoff Time | Interest | Total Cost | Total Paid |
|---|
How the payment changes the result
Your payment, the payment that clears the balance inside the promotion, and a payment 25% above yours. The leftover column shows what would roll to the regular rate. The savings column compares each payment with keeping the balance on the current card at that same payment, so it shrinks as the payment rises: a bigger payment makes both paths cheaper.
| Monthly Payment | Left at Promo End | Payoff Time | Transfer Cost | Saved vs Staying |
|---|
Example: $6,000 at 24.99%
Suppose $6,000 sits on a card at 24.99% APR and you pay $300 a month. Left where it is, the balance takes 27 months to pay off and costs $1,841.43 in interest.
Now take an offer with a 3% fee and 0% for 18 months, then 24.99%. The fee adds $180, so you start at $6,180. Eighteen payments of $300 remove $5,400, leaving $780 when the promotion ends. That remainder costs $30.87 in interest, and the balance is gone in month 21. The total cost is $210.87, which saves $1,630.56. With these terms, the fee would have to reach about 27% before the transfer stopped saving money.
Paying $343.34 a month instead clears the $6,180 inside the 18 months, so nothing reaches the regular rate and the only cost is the $180 fee.
The same leftover is far more expensive under a deferred interest plan, the kind of promotion common on store cards. There, a balance left at the end can trigger interest on every month's balance back to the start. On this payment path, that would be about $1,360.71, most of the savings gone because $780 was still owed.
What the Consumer Financial Protection Bureau says
A card company is permitted to charge a balance transfer fee on a zero percent offer. An introductory rate has to stay in effect for at least six months, unless you are more than 60 days late on a payment, and the issuer must tell you how long it lasts and what rate applies afterward.
Two details catch people. First, if you carry a balance, new purchases on most cards accrue interest from the transaction date, even while the transferred balance is at 0%. Second, a deferred interest plan is different from a 0% introductory rate: if the balance is not paid in full by the end, or you are more than 60 days late, you can owe interest back to the original date.
When a transfer is the wrong move
A transfer works best when the current rate is high, the promotional period is long, and you can pay the clearing amount every month. It works poorly when the fee is high and the promotion is short, when the rate after the promotion is higher than your current rate and a large balance would be left, or when the new card becomes a place to spend again.
If the clearing payment is out of reach, the transfer can still help, but treat the promotional end date as a deadline. Set the payment as high as you can sustain, keep the old card's balance at zero, and avoid purchases on the new card until the transferred balance is gone.
Mistakes that erase the savings
- Forgetting the fee when comparing offers. A longer promotion with a higher fee can still win, but only the full cost shows it.
- Paying the minimum during the promotion and leaving most of the balance for the regular rate.
- Using the new card for purchases, which can start interest on those purchases right away.
- Missing a payment and losing the promotional rate early.
- Treating a deferred interest store offer like a 0% balance transfer.
- Running the old card back up after the transfer, ending with two balances instead of one.
How the comparison is calculated
Each month, interest is charged on the balance at the rate in effect, rounded to the cent, and then the payment is applied. The current card uses its APR every month. The transfer starts at the balance plus the fee, uses the promotional APR for the promotional months, and the post-promotion APR after that. Both paths stop when the balance reaches zero or after 1,200 months.
The clearing payment is the fixed payment that brings the transferred balance to zero by the last promotional month. Real cards may compute interest daily, set minimum payments differently, or apply payments across balances in a set order. Review the methodology limitations before relying on an exact month.
Good fits
- Checking whether one offer saves money after its fee.
- Comparing two offers by running each one.
- Finding the payment that clears a balance in time.
- Seeing the cost of a balance left after the promotion.
Limits
- Deferred interest store cards, except as a warning.
- Cards with several balances at different rates.
- Debt consolidation loans or settlement.
- Credit score effects of opening a new card.
Balance transfer questions
These answers cover how transfers work and what the calculator assumes.
Is a balance transfer worth it with a fee?
Often, if the interest you avoid is larger than the fee. The calculator compares the fee plus any interest after the promotion with the interest you would pay by keeping the balance where it is.
Can a card charge a fee on a 0% offer?
Yes. A card company is permitted to charge a balance transfer fee on a zero percent offer. The fee is usually added to the transferred balance.
How long does a 0% introductory rate last?
The offer states the length. An introductory rate generally has to last at least six months, unless you are more than 60 days late on a payment.
What happens to the balance left when the promotion ends?
It starts accruing interest at the rate stated for after the promotion. The calculator shows that leftover amount and the payment that would clear the balance in time.
Do new purchases on the card get the 0% rate?
Usually not. If you carry a balance, purchases on most cards accrue interest from the transaction date, even while a transferred balance sits at 0%.
Is a 0% transfer the same as deferred interest?
No. With a 0% introductory rate, interest starts only on what remains after the promotion. With deferred interest, any balance left at the end can trigger interest back to the original date.
Does a missed payment end the promotion?
It can. Check the offer terms. Being more than 60 days late can end an introductory rate early, and a single late payment can bring fees.
Is this financial advice?
No. It is an educational estimate, not financial, credit, or legal advice. Confirm every term in the written offer before moving a balance.
Plan the payoff
Credit Card Payoff CalculatorPayoff time and minimum payments on one cardDebt Avalanche vs Snowball CalculatorPayoff order across several debtsPay Off a $5,000 Credit CardA worked single-card scenarioCalculator MethodologyFormulas and limitationsDisclaimerEducational scope and limits
Educational estimate only. This calculator does not provide financial, credit, or legal advice. Use it to compare a transfer offer with staying put, then confirm every term in the written offer before moving a balance.