How a transfer works
A balance transfer moves debt from one card to another card offering a low promotional rate, often 0% for a set number of months. There's usually a fee, commonly 3% to 5% of the amount moved, added to the new balance up front. After the promo ends, the regular APR applies to whatever is left.
The example
$5,000 at 22.15%, paying $300 a month, takes 21 months and costs about $1,031 in interest. Transfer it to a 0% offer for 15 months with a 3% fee: the fee is $150, so the new balance is $5,150. Paying $300 a month, $650 is left when the promo ends, and about $20 of interest follows before it's paid off in month 18. Total cost: about $170. With a 5% fee, it's about $276.
Clearing it inside the promo
To pay off the whole transferred balance before the promo ends, divide the new balance by the promo months: $5,150 ÷ 15 ≈ $343.33 a month. At a 0% promo that number is exact. Any amount left after the promo starts getting charged the regular rate.
The fine print that changes the math
Promotional rates must last at least 6 months under the CARD Act. New purchases on the new card may get the regular APR, and payments above the minimum generally go to the highest-rate balance first. Paying 60 or more days late can end a promo rate early (Regulation Z §1026.55). Store-card "deferred interest" promotions are different: if the balance isn't paid in full by the end, interest can be charged back to the purchase date.
What the page compares
The chart shows both balances over time with a line where the promo ends, and the total-cost bars show staying put versus a 3% and a 5% fee. If your payment doesn't cover the interest on either path, the page says so rather than showing a payoff that never happens.
Assumptions
No new charges, a fixed monthly payment, monthly interest (APR ÷ 12) and the rates you enter. No card or issuer is named here; offers vary.
Sources
- Federal Reserve: G.19 Consumer Credit
- Regulation Z §1026.55 (rate increases and promotional rates)
- CFPB: Credit cards
Last reviewed: Sep 28, 2026