U.S. · credit cards
Balance transfer calculator.
Compare staying on your current card with moving the balance to a promotional rate, fee included, month by month.
A balance transfer pays off when the interest you avoid is larger than the transfer fee. Moving $5,000 from a 24.99% card to a 0% offer with a 3% fee for 15 months, paying $250 a month, costs a $150 fee and about $104.08 of interest, against $1,534.53 if you stay.
Your numbers
Result
How this is calculated
Each month the calculator adds a month of interest (APR divided by 12 on the running balance), then subtracts your payment. For the transfer it starts from the balance plus the fee, uses the promotional APR for the promotional months, and the post-promotion APR after that. The result is the interest you would pay in each case, with the transfer fee added to the cost of moving. Whichever total is smaller wins; the page also shows the balance left when the promotion ends, because that is the part that starts costing interest again.
Three rules from Regulation Z matter here. The issuer must list the balance transfer fee in the table you get with the application (12 CFR 1026.60(b)(11)). A temporary rate that the issuer wants to end by raising the rate must run six months or longer, and the length and the later rate must be disclosed in writing first (1026.55(b)(1)). And any payment above the minimum goes first to the balance with the highest APR (1026.53), so a transferred 0% balance is paid down last if the card also carries new purchases at a higher rate.
Worked example
$5,000 at 24.99%, moved to 0% for 15 months, 3% fee, $250 a month. Fee: $5,000 × 3% = $150. Staying put, $250 a month clears the card in 27 payments with $1,534.53 of interest. After moving, the balance is $5,150; after 15 payments of $250 you still owe $1,400, which then accrues interest at 24.99%. Total interest on the new card is $104.08, payoff takes 22 payments, and the cost of moving (interest plus fee) is $254.08. You keep $1,280.45.
Try a 5% fee and a 6-month promotion at $250 a month and the saving shrinks quickly: a short promotion leaves most of the balance exposed to the regular rate.
Limits of this estimate
It assumes no new purchases, a payment that never changes, and monthly compounding of the stated APR. Real cards compound daily and may have a grace-period rule, a minimum interest charge, or a promotional rate that ends early if you pay late.
Sources
Primary sources opened and checked on October 26, 2026. Figures are as published on that date and are not a prediction of your own terms.
Common mix-ups
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Often assumedAny extra I pay will go to the 0% transferred balance first, so my payments always attack it.
What the source saysUnder 12 CFR 1026.53, the part of a payment above the minimum goes first to the balance with the highest APR, then to the others in descending order. If new purchases on the card carry a higher rate, that is where the extra goes. [1]
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Often assumedA card issuer can end a promotional rate and raise the rate after only a month or two.
What the source saysThe exception that lets an issuer raise a rate when a temporary rate expires applies to a specified period of six months or longer, and the issuer must disclose the period and the later rate in writing before it starts (12 CFR 1026.55(b)(1)). [2]
- eCFR: 12 CFR 1026.53, allocation of payments
- eCFR: 12 CFR 1026.55, limitations on increasing rates, fees and charges
Checked against these sources on .
Frequently asked questions
Is a balance transfer fee worth paying?
It is worth paying when the interest you avoid during the promotional period is greater than the fee. Enter your balance, both rates and your real monthly payment; the page shows the cost of moving, fee included, next to the cost of staying.
Where do I find the balance transfer fee?
In the rate and fee table that comes with the card application. Regulation Z requires that table to list any fee imposed to transfer an outstanding balance (12 CFR 1026.60(b)(11)). It is usually a percentage of the amount moved, sometimes with a minimum dollar amount.
How long does a promotional rate have to last?
If the issuer wants the right to raise the rate when a temporary rate ends, the period must be six months or longer, and the issuer must tell you in writing how long it lasts and what rate applies afterward (12 CFR 1026.55(b)(1)). The rule has exceptions, so read your card agreement.
Where do extra payments go if I make new purchases on the card?
Anything above the minimum goes first to the balance with the highest APR and then to the others in descending order (12 CFR 1026.53). That can leave a 0% transferred balance untouched while you pay down a purchase balance.
What if the balance is not paid off when the promotion ends?
The remaining balance is charged the post-promotion APR you entered. The result shows how much is still owed at that point so you can see how much interest is exposed.
Not financial advice
This page is general information, not financial, legal or tax advice. Your loan, card or plan terms control and may differ from the examples. Confirm anything that matters with your lender, bank, insurer or a qualified adviser before you act. Everything runs in your browser; nothing you enter is sent anywhere.