Balance Transfer Calculator: Does the 0% Offer Beat the Fee?
A 0% intro card charges a 3-5% transfer fee upfront. See whether the interest you'd save during the intro window actually clears that fee — and whether you'll pay off the balance before the 0% expires and the go-to APR kicks in. Math runs locally.
The fee is the whole question
A balance transfer trades a known upfront cost (the fee) for a stretch of cheap or free interest. The math only works if the interest you'd otherwise pay is bigger than the fee. On a $5,000 balance at 22% APR paying $250/month, staying put costs about $1,286 in interest over 26 months. Move it to a 0% card with a 3% ($150) fee and — even if you don't fully clear it inside an 18-month window — you pay roughly $23 of interest plus the $150 fee, netting about $1,100 in savings. The fee paid for itself many times over.
Flip the inputs and it stops working: a 5% fee, a 6-month window, and a go-to APR barely below your current rate can leave the transfer costing more than staying. That's exactly the comparison this tool makes explicit instead of leaving to the marketing copy.
How the math works
- Transfer fee = fee % × balance, added to the new card's starting balance.
- Stay path: the balance is amortized month by month at the current APR with your fixed payment.
- Transfer path: (balance + fee) is amortized at the intro APR for the intro months, then at the go-to APR for any remainder.
- Net savings = stay-path total cost − (transfer interest + fee). Positive means transferring wins. The tool also flags whether you clear the balance before the intro rate expires.
Source: CFPB — what is a balance transfer (3-5% fee norm, intro-rate mechanics) and the Federal Reserve G.19 series for current APRs.
Math runs locally. Inputs never leave your browser. Source on github.
Where this doesn't apply
- You'll keep charging the new card. New purchases on a balance-transfer card often don't get the 0% rate and can complicate how payments are applied. The strategy assumes you stop adding to the balance.
- Your approved limit is below the balance. Issuers may approve a transfer limit smaller than what you owe, leaving part of the balance on the old card at the old rate. Then you're running both calculations at once.
- You're chasing a credit milestone soon. A new-card application is a hard inquiry and lowers your average account age — both can ding your score for a few months, which matters if you're about to apply for a mortgage.
- You won't actually change the payment. A transfer only helps if you keep paying steadily through the intro window. If the 0% just becomes an excuse to pay less, the leftover balance hits the go-to APR and the fee was wasted.
What to actually do
- Set the monthly payment to (balance + fee) ÷ intro months — that's the amount that clears it with zero interest before the rate jumps.
- Compare offers on fee and window length, not just the headline 0%. A longer 0% window with a 3% fee usually beats a shorter one with no fee.
- Stop using the old card for purchases so the balance only goes down.
- If you can't clear it in the window, check what's left at the go-to APR here — then line up the next move before the rate resets.
- If the transfer doesn't come out ahead, a steady fixed payment on your current card (see the Credit Card Payoff tool) may be the cheaper route.