Balance Transfer Savings Calculator

• Compares total interest plus the transfer fee against staying on the current card, at the same monthly payment.
• Models both the promotional period and what happens to any balance left over once it ends.
• Flags when a planned payment wouldn't even cover interest on the current card, which can make a transfer look artificially favorable.
• Shows a month-by-month balance comparison between the two paths.

How to use this calculator

Enter the current balance, its APR, and the monthly payment planned regardless of which path is taken — this is what makes the comparison fair, since a larger payment always pays off faster on either card. Add the balance transfer fee percentage, the promotional APR (often 0%), how many months it lasts, and the regular APR that applies to whatever's left once the promo period ends.

How the comparison works

Two scenarios are simulated month by month with the identical monthly payment:

Stay:     pay down the current balance at its current APR until paid off
Transfer: add the fee to the balance, pay at the promo APR until the promo
          ends or it's paid off, then pay any remainder at the go-to APR

The total cost of each path — all interest paid, plus the one-time transfer fee on the transfer path — is what gets compared, not just the headline promotional rate.

A worked example

A $6,000 balance at 22% APR, paid down at $250 a month, racks up a meaningful amount of interest over time. Transfer that same balance to a card with a 3% transfer fee ($180) and a 0% promo rate for 15 months, still paying $250 a month, and the balance shrinks by the full payment amount each month during the promo period with no interest at all — typically clearing most or all of the balance before the promo ends, for a total cost close to just the $180 fee.

What to watch out for

The biggest risk in a real balance transfer isn't the math — it's what happens after the promo period. If the balance isn't cleared by then, whatever remains reverts to the card's regular ongoing APR, which is often similar to or higher than a typical credit card rate. This calculator models that transition directly so it isn't a surprise: if the payment entered wouldn't fully clear the balance within the promo window, the results show what carries over and at what rate.

Assumptions and limitations

• Assumes the same fixed monthly payment in both scenarios — a real budget might change, and a card's minimum payment requirements aren't modelled separately.
• No new charges are added to either card during the period modelled — this is a payoff comparison, not a spending simulation.
• Doesn't model credit score effects. Opening a new card affects credit utilization and average account age, which can move a score temporarily in either direction.

Common mistakes

Focusing only on the promotional rate and ignoring the fee. A 0% offer with a high transfer fee on a small balance that would have been paid off quickly anyway can end up costing more than just paying the original card down directly.

Not budgeting to clear the balance before the promo ends. The biggest savings come from paying off the transferred balance within the promotional window — carrying a balance past it into the regular APR erodes much of the benefit.

Treating a balance transfer as new available credit to spend. The purpose of a transfer is to pay down existing debt more cheaply, not to free up room for new purchases on either card.

Frequently asked questions