A 0% promo wins only if the fee is smaller than avoided interest and the balance is gone before reset.
A balance transfer is worth it only when the interest you avoid is larger than the transfer fee and you can clear the balance before the promo APR resets. You pay a one-time fee of usually 3–5% to move debt onto a card that charges 0% for a fixed window; if the balance is gone by the deadline you skip months of high interest. If it is not gone, the leftover snaps to the regular APR and the math can flip against you. This tool runs both scenarios on your numbers and shows the net saving, the fee cost, and the payment you need.
The moment you transfer, the fee is added to your balance. During the promo every payment is pure principal because nothing accrues. If a balance is still left when the promo ends, it begins accruing at the post-promo APR. The tool compares two worlds: keep the debt on the old card versus transfer it.
fee% — one-time transfer fee, typically 3%–5% of the amount movedpromo months — the 0% window, usually 12–21 monthsCompare the fee to the interest you would otherwise pay. A 4% fee on a balance you would have carried at 24% for a year and a half is trivial — the avoided interest dwarfs it. The danger is never the fee; it is failing to clear the balance before reset.
Lower the payment, shorten the promo, or raise the fee on the left and watch the verdict flip in your browser.
The fee is small and predictable. The risk is the leftover balance at reset and a slip that voids the promo. A missed payment can snap you to the regular or a penalty APR instantly.
| Scenario | Outcome | Why |
|---|---|---|
| Cleared before promo ends | Best case | Only cost is the one-time fee |
| Balance left at reset | Partial win | Leftover accrues at post-promo APR |
| Missed a payment | Risk | Promo can be voided; penalty APR applies |
| Deferred-interest offer | Worst case | Retroactive interest on the full original balance |
| Behavior depends on your card agreement. Read the offer terms before applying. | ||
You move debt from a high-rate card to a new card that charges 0% interest for a promotional window, typically 12 to 21 months. During the promo every dollar you pay reduces principal because no interest accrues. When the promo ends, any remaining balance starts accruing interest at the card's regular APR.
Most cards charge a one-time transfer fee of 3% to 5% of the amount moved, added to your balance immediately. On the default $7,000 transfer at a 4% fee, that is $280 added up front, so you start the promo owing $7,280. The transfer is only worth it when the interest you avoid is larger than this fee.
With a true 0% APR balance transfer, interest only starts on whatever balance remains after the promo ends. With deferred interest (common on store financing), interest is silently accruing the whole time and is charged retroactively on the entire original balance if any amount remains when the promo ends. Deferred-interest offers are far riskier.
Opening the new card adds a hard inquiry and lowers your average account age, which can dip your score a few points short term. But moving balances to a new card with a higher limit can lower your overall credit utilization, which often helps the score within a few months — provided you do not run the old card back up.
A single late payment can void the promotional 0% APR entirely, snapping the balance to the regular or even a penalty APR immediately. Penalty APRs can exceed 29%. Automate at least the minimum payment so one missed due date does not erase the whole benefit.
Divide the post-fee balance by the number of promo months. On the default example, $7,280 over 18 months is about $404 per month to finish exactly at the deadline. Paying the default $450 a month clears it inside the promo with room to spare.
Yes. Transferring $7,000 at a 4% fee ($280) and paying $450 a month clears the balance inside the 18-month 0% promo. Keeping it on the 24% card instead would cost roughly $1,469 in interest, so the transfer saves about $1,189 net of the fee.
Transfer the balance you can realistically clear before the promo ends, prioritizing your highest-APR debt. Transferring more than you can pay off in time means the leftover gets hit with the post-promo APR, which can erase the savings. Do not transfer a balance you cannot fund a real payoff plan for — the debt payoff calculator helps you build that plan.
Usually not. Most issuers do not allow balance transfers between two of their own cards, so a 0% offer normally has to come from a different bank. Always read the offer terms before applying.
No. Everything runs in your browser and nothing is sent to a server. Share links include the numbers as visible URL parameters, so avoid sharing a link if the balance is private.
Educational only, not financial advice. Real offers vary on fee, promo length, penalty APR, and deferred-interest terms — read the card agreement before transferring.