Balance Transfer Calculator
Transfer fee vs interest savings ROI — is the 0% promo worth it?
Transfer saves you
$1,129
Transfer wins if (current APR × promo months) > transfer fee. Always pay enough during promo to clear balance before APR kicks in.
A balance transfer moves debt from a high-APR card to a card with a low or 0% introductory APR, so more of each payment goes to principal instead of interest. In exchange, you usually pay an upfront transfer fee.
The math is a trade-off: you pay a fee today to stop paying interest during the promo window. This calculator compares that fee against the interest you would otherwise owe, and shows whether you can clear the balance before the 0% period ends.
The strategy works best when you have a concrete payoff plan. If interest resumes on a leftover balance after the promo, the savings can shrink fast.
How this calculator works
The transfer fee is typically 3-5% of the amount moved: transferring $6,000 at a 3% fee costs $180 upfront. Against that, the tool estimates the interest you would have paid on your old card. At 22% APR, a $6,000 balance accrues roughly $110 in interest in the first month alone (6000 x 0.22 / 12), and much more over a year of paying it down slowly. If the new card offers 0% for, say, 15 months, none of that interest accrues during the promo, so the only cost is the $180 fee. The calculator finds your breakeven (the fee divided by your monthly interest savings tells you how quickly the fee pays for itself), and it works out the monthly payment needed to clear the balance before the intro period ends, since any remaining balance then starts accruing at the card's regular APR.
What affects the number
- Transfer fee: usually 3-5% of the amount moved (sometimes a flat minimum), paid upfront and added to the new balance.
- Promo length: 0% intro periods commonly run 12-21 months; a longer window gives you more time to pay principal without interest.
- Payoff plan: divide the balance by the number of promo months to find the payment that clears it in time; falling short leaves a balance exposed to the regular APR.
- Post-promo APR: interest resumes on any remaining balance once the intro period ends, so the go-to rate matters if you might not finish in time.
- New purchases: many cards do not extend the 0% offer to new purchases, which can accrue interest immediately and complicate payment allocation.
- Eligibility: intro offers require good credit, you usually cannot transfer between cards from the same issuer, and each card caps how much you can transfer.
Frequently asked questions
Is a balance transfer worth the fee?
It is worth it when the interest you avoid during the 0% period exceeds the upfront transfer fee, which is usually the case if your current APR is high and you can pay the balance down during the promo. Divide the fee by your monthly interest savings to see how fast it pays for itself; a few months is common on high-APR debt.
What happens if I do not pay off the balance before the 0% period ends?
The remaining balance starts accruing interest at the card's regular (go-to) APR, which can be high. Unlike deferred-interest store financing, standard balance transfer cards do not usually charge back-interest on what you already paid, but any leftover balance is now costly. Aim to clear it before the promo ends.
How is the balance transfer fee calculated?
It is a percentage of the amount you move, typically 3-5%, often with a minimum of about $5. Transferring $4,000 at a 3% fee costs $120, added to your new balance. A handful of cards run no-fee promotions, which changes the math entirely in your favor.
Do new purchases get the 0% intro APR too?
Often not. Many cards apply the 0% rate only to the transferred balance, while new purchases accrue interest at the standard rate. Making purchases can also complicate how payments are applied, so it is usually best to avoid using the card for spending until the transferred balance is paid off.
This calculator provides general estimates for educational purposes only and is not financial advice. Your actual costs and credit outcomes depend on your specific card terms, issuer, and situation.