What Is a Balance Transfer Break-Even Calculator?

A balance transfer break-even calculator answers one question before you move a balance: how long will it take for the interest you avoid to outweigh the fee you pay? Transfers usually carry a one-time fee of 2% to 5% of the amount moved, and a promotional rate — often 0% — that lasts for a fixed window before the balance reverts to a standard APR. Whether the deal wins depends on the size of the fee, the length of the promo window, the rate the balance would otherwise carry, and how fast you repay.

The break-even month is the decision rule. If it arrives well inside the promotional period and you can clear the balance before the rate reverts, the transfer is a straightforward saving. If the promotional period is shorter than break-even, or if the balance rolls into a post-promo rate that is no better than the rate you started with, the transfer can cost more than doing nothing — a result that is easy to miss when the headline says "0% for 12 months".

How It Works

The calculator simulates two repayment schedules with the same monthly payment. In the first, the balance is repaid at your current APR throughout. In the second, the transfer fee is added to the balance and the balance is charged the promotional rate for the promo window, then the post-promotional rate on whatever remains. Both schedules record each month's interest charge and cumulative interest.

Break-even is found by comparing the cumulative interest difference month by month: the first month in which the interest avoided exceeds the fee is the break-even point. Net savings is the interest paid at the current rate minus the interest paid on the transfer path, minus the fee. The calculator also reports the balance remaining when the promo window ends, so you can see whether the plan actually clears inside it, and separates the interest saved during the promo from interest paid afterwards.

Understanding Your Results

The primary card reports net savings after the fee, with a note on whether the balance clears within the promotional window. The three-stat bar shows the fee, the interest saved during the promo period and the break-even month, and the breakdown table lines up both paths — interest with and without the transfer, the fee and the net saving — with the payoff timeline for each.

Summary Statistics adds the interest split between the promo and post-promo periods, the balance remaining at the promo end, the two payoff durations and both rate comparisons. Treat the post-promo rate as the number that decides the trade: a transfer only wins if you make real progress during the promotional window, and the fastest way to guarantee that is to set the payment so the projected payoff lands inside it. If the numbers say break-even comes after the promo expires, the honest answer is that this transfer is not worth the fee. Test the sensitivity before committing: nudging the payment up a little, or the promo period down a month, often flips a marginal offer from a small win to a clear loss.