Balance Transfer Calculator

How the math works

The transfer path starts at your balance plus the fee, pays 0% for the promo months, then charges the after-promo rate on whatever is left. The stay path keeps your balance at its current APR. Both get the same monthly payment, and both run month by month until the balance is gone. The break-even month is the first month the interest you’ve avoided is bigger than the fee you paid. Total paid is the balance, plus the fee, plus the interest, and the difference between the two totals is the saving.

The fee is paid on day one and the saving arrives a month at a time, so a transfer only pays off if you keep making the payments. The payment that clears the balance inside the promo (the balance plus the fee, divided by the promo months) is the number to plan around. Anything less leaves a tail at the after-promo rate, and the calculator prices that tail.

Before you apply

• A missed or late payment can void the promo. Most agreements let the issuer end the 0% rate and charge the regular APR from then on, so set up autopay for at least the minimum.
• New purchases usually don’t get the promo rate. They accrue at the regular purchase APR, so use the card for the transfer and nothing else until it’s paid.
• The application is a hard inquiry, and the card’s credit limit caps what you can move. If the limit comes in under your balance, transfer what fits and keep paying the rest where it is.
• Check the fee against the interest, not against the balance. A 3% fee on a card at 24.99% is recovered in a couple of months; the same fee on a 9% loan may never be.

Balance transfer vs deferred interest

A 0% balance transfer waives the interest for the promo period. When it ends, the after-promo rate applies to what’s left, and nothing is charged for the months that passed. A deferred-interest promo, the store-card kind that says “no interest if paid in full,” is different: the interest accrues from day one and is billed all at once if any balance remains at the deadline. If your offer says “if paid in full,” use the deferred interest calculator instead.

Frequently asked questions

Is a balance transfer fee worth it?

When the interest you avoid during the 0% period is bigger than the fee, yes. On a high-rate card that usually happens within the first few months, and this calculator shows the month it does. It stops being worth it when the balance is small, the current rate is low, or the payment is so small that most of the balance is still there when the promo ends.

What is a typical balance transfer fee?

Most offers charge 3% to 5% of the amount transferred, added to the new balance. A few cards waive the fee for a short window after opening. A $6,000.00 transfer at 3% costs $180.00 up front, which is the number the interest has to beat.

What happens when the 0% period ends?

Whatever is left starts accruing at the card’s regular purchase or balance-transfer APR from that point on. Nothing is charged for the months that passed. That is the difference from a deferred-interest promo, which bills every month of accrued interest at once if the balance isn’t cleared in time.

What if I can’t pay it off inside the promo?

You still usually come out ahead if the fee is small next to the interest you avoided, but the tail costs money. The calculator shows what is left when the promo ends and what that tail costs at the after-promo rate. If the tail is large, transfer only what you can clear in time, or look for a longer 0% period.

Does a balance transfer hurt my credit?

The application is a hard inquiry, and a new account lowers the average age of your accounts. Moving a balance can also lower your utilization on the old card if you keep it open. The bigger risk is behavioral: running the old card back up while you pay off the new one.

Can I make new purchases on the transfer card?

You can, but new purchases usually don’t get the promo rate. They accrue at the card’s regular purchase APR, and on many cards there is no grace period on purchases while a transferred balance is carried. Use the card for the transfer and nothing else until it’s paid.

Is anything I type stored or sent anywhere?

No. The calculator runs in your browser. Your numbers never leave this page, nothing is saved, and there’s no account or sign-up. Leave or refresh the page and they’re gone. The Debt Descent app works on the same principle: its App Privacy label is “Data Not Collected.”

How does Debt Descent model a balance transfer?

Its Refinance & consolidation tool (part of the one-time Pro purchase) models a balance transfer with the fee and the promo period against the debts you already track, holding your total monthly payment constant. When you take the offer, you apply the deal in one step instead of re-entering everything.

More free tools

• Debt Snowball & Avalanche Calculator: your debt-free date and total interest, both methods side by side.
• Deferred Interest Calculator: what a “no interest if paid in full” promo bills if you miss the deadline.
• Debt Management Plan Calculator: a DMP’s reduced rate and fees against paying on your own.

All of them run in your browser and send nothing back to me. They come from Debt Descent, my debt-payoff app for iPhone, iPad, and Mac. If you’re weighing it against another planner, I’ve written up Debt Descent vs Undebt.it and Debt Descent vs Debt Payoff Planner.