Balance Transfer Calculator
A 0% promo with a 3% fee and an expiry date: worth it, or a trap? Compare staying against transferring — fee, promo window and the rate after it all counted.
The promo is a deadline wearing a discount
A balance transfer offers a low rate for a fixed window, charges a fee for the privilege, and — written in the same contract — restores a full go-to APR the day the window closes. Whether it saves money depends on one fact: how much balance is still alive when the music stops.
Net saving = interest if you stay − (transfer fee + interest on the transfer path)
Example: $6,000 at 26% paid at $250 a month costs about $2,490 of interest staying put. Transfer at 0% for 18 months with a 3% fee ($180): if the $250 payments kill the balance inside the window, interest is near zero and the saving is about $2,300. Halve the payment, let a balance survive into the 26% go-to rate, and the saving can evaporate entirely.
The two failure modes, named
First: spending on the new card, which grows the balance the promo was meant to shrink (and promo purchases may not share the promo rate). Second: the minimum-payment drift — paying the small required minimum during 0% months because nothing seems urgent, arriving at expiry with the debt intact. The transfer rewards a fixed, aggressive payment and punishes vibes.
How this is calculated
Both paths use the published daily-balance model (30-day cycles, interest = balance × APR ÷ 365 × 30, payment at cycle end). The stay path runs your current APR throughout. The transfer path adds the fee to the balance, charges the promo APR for the promo cycles, then your go-to APR, using the same payment. Net saving = stay interest − fee − transfer interest. If your payment cannot clear the debt at the current APR, the page says so before comparing.
Frequently asked questions
When is a balance transfer clearly worth it?
When the fee is small relative to the interest avoided and your payment clears the balance comfortably inside the promo — the larger the buffer before expiry, the safer the bet.
Does the transfer fee get the promo rate?
Usually the fee is added to the transferred balance and shares its promo rate on most offers — the model here includes it in the balance from day one. Your offer's terms govern; some issuers treat fees differently.
Can I lose the promo rate?
Yes — a late payment can void the promotional APR on many cards, converting the whole exercise into an expensive mistake. Autopay for at least the minimum is not optional hygiene; it is the deal's protection.
What happens to my credit score?
A new application and account cause a small temporary dip; reducing utilization on the old card usually helps more over the following months. Opening the card and re-filling it is the one path that reliably makes both the debt and the score worse.
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