Debt / THE DECISION DESK
Balance Transfer Calculator
Weigh a 0% transfer offer against staying put, counting the up-front fee and what happens to anything left when the promotional rate ends.
Reviewed Calculation inputs stay in your browser
Compare up to three snapshots of inputs and headline results. Snapshots clear when you leave this page.
$2,033
Comparing total interest and fees either way, at $400 a month.
Stay put
Transfer
The promo window
Balance under each option
The transfer line starts slightly higher because the fee is added to the balance, then falls faster while the promotional rate holds. If it has not reached zero by the marked line, the remainder starts accruing at the revert rate.
View as table
| Months from today | Stay put | Transfer |
|---|---|---|
| 0 mo | $8,000 | $8,240 |
| 1 mo | $7,760 | $7,840 |
| 2 mo | $7,515 | $7,440 |
| 3 mo | $7,265 | $7,040 |
| 4 mo | $7,011 | $6,640 |
| 5 mo | $6,751 | $6,240 |
| 6 mo | $6,486 | $5,840 |
| 7 mo | $6,215 | $5,440 |
| 8 mo | $5,940 | $5,040 |
| 9 mo | $5,658 | $4,640 |
| 10 mo | $5,371 | $4,240 |
| 11 mo | $5,079 | $3,840 |
| 1 yr | $4,780 | $3,440 |
| 1 yr 1 mo | $4,476 | $3,040 |
| 1 yr 2 mo | $4,165 | $2,640 |
| 1 yr 3 mo | $3,849 | $2,240 |
| 1 yr 4 mo | $3,526 | $1,840 |
| 1 yr 5 mo | $3,196 | $1,440 |
| 1 yr 6 mo | $2,860 | $1,040 |
| 1 yr 7 mo | $2,517 | $663 |
| 1 yr 8 mo | $2,167 | $278 |
| 1 yr 9 mo | $1,811 | $0 |
| 1 yr 10 mo | $1,447 | $0 |
| 1 yr 11 mo | $1,076 | $0 |
| 2 yr | $697 | $0 |
| 2 yr 1 mo | $311 | $0 |
| 2 yr 2 mo | $0 | $0 |
How this is calculated
Two month-by-month simulations run against the same monthly payment, so the only thing that differs between them is the offer itself.
stay: apr = current rate throughout
transfer: balance starts at balance × (1 + fee rate)
apr = promo rate while month < promo length
revert rate afterwards
The fee is added to the balance rather than treated as a separate cost, which is how issuers actually apply it — meaning you pay interest on the fee too once the promotional period ends.
Holding the payment identical across both scenarios is deliberate. A transfer that appears to win only because you also assumed a larger payment is not telling you anything about the offer.
Not modelled: new spending on either card, being approved for less than the full balance (common, and it leaves the remainder behind at the old rate), deferred-interest structures, or promotional rates that end early on a missed payment.
Common questions
›Is a 3% transfer fee worth paying?
Usually yes, if the rate gap is wide and you will make real progress during the promotional window. Moving $8,000 from 24% costs $240 up front but avoids roughly $1,600 a year in interest, so the fee pays for itself in under two months. It stops being worth it when the current rate is already low, the promo is short, or the payment is small enough that most of the balance is still there when the promotional rate ends.
›What happens if I do not clear it before the promo ends?
Whatever is left starts accruing at the revert rate, which is frequently higher than the rate you left. That does not automatically make the transfer a mistake — you still had months of interest-free progress — but it is the difference between a good outcome and a great one. The tool reports the payment that would clear the balance inside the window, which is the number worth aiming at.
›Is deferred interest the same as 0% APR?
No, and confusing the two is expensive. A genuine 0% balance transfer charges nothing during the promotional period. Deferred interest, more common on store cards and retail financing, accrues interest the whole time and waives it only if the entire balance is cleared by the deadline — miss it by a dollar and the full accrued amount is added retroactively. Check which one an offer actually is before relying on it.
›Will a balance transfer hurt my credit score?
There is usually a small, temporary dip from the hard inquiry and the new account lowering your average account age. Against that, moving a balance onto a larger credit line often reduces overall utilisation, which helps. The net effect is typically mildly positive within a few months, provided you do not run the old card back up — which is the behaviour that actually causes damage.
›Why does the fee get added to the balance?
Because that is how issuers apply it. The fee is charged to the new card rather than billed separately, so it becomes part of the transferred balance and accrues interest along with everything else once the promotional period ends. Treating it as a separate up-front cost slightly understates what a transfer really costs, so this calculator adds it to the balance the way a statement would.