Balance transfer breakeven calculator

Key takeaway: A balance transfer isn't automatically a win — it's a race between the interest you save at the promo rate and the fee you pay up front. This calculator runs both paths month by month so you can see exactly when (or if) transferring pulls ahead.

Why compare full schedules instead of just the fee vs. the rate?

A quick mental comparison ("3% fee vs. saving 20 points of APR") misses timing: the fee is charged immediately, in full, while interest savings accrue gradually over the promo period and can be interrupted by a post-promo rate hike on whatever balance remains. Running both scenarios — keep the current card, or transfer — as full month-by-month schedules is the only way to see the actual crossover point, if there is one.

When does transferring stop making sense?

Three situations tend to erase the benefit: a short promo period relative to how long payoff takes, a high transfer fee relative to the balance, or a post-promo rate that's not meaningfully lower than what you're paying now. If your result shows "never" for the breakeven month, one of those is likely the culprit — try shortening your target payoff time with the target-months calculator to see if a faster payoff would fit inside the promo window instead.

How we calculate this

We run two full amortization paths with the same monthly payment: one at your current APR with no changes, and one where the balance (plus the capitalized transfer fee) is paid down at the promo APR until the promo period ends, then continues at the post-promo APR if anything remains. We compare running totals of what's actually been paid in each path, month by month, to find the point where transferring becomes — and stays — the cheaper option.

Frequently asked questions

Why would a balance transfer ever cost more than just keeping my card?

Transfer fees (typically 3–5% of the balance) are capitalized onto the new balance immediately, before any interest savings have had a chance to accrue. If you'd pay the balance off quickly anyway, or the promo period is short, the fee can outweigh the interest you save.

What happens if I don't pay off the balance before the promo APR ends?

Whatever's left reverts to the post-promo APR, which is often close to a typical card's regular rate. This calculator models that transition explicitly, so the breakeven month already accounts for any interest charged after the promo window closes.

Does a shorter promo period always mean transferring is worse?

Not necessarily — it depends on how quickly you'd pay off the balance anyway. If your payment clears the balance within the promo window regardless of length, a shorter promo can still fully avoid post-promo interest; the calculator's breakeven month tells you which case you're in.

Sources

• Consumer Financial Protection Bureau, Balance transfers
• Federal Reserve, G.19 Consumer Credit report (Federal Reserve G.19 Consumer Credit report, as of 2026-05-01)