A balance transfer moves debt from a high-rate card onto a new card offering 0% interest for a promotional window, usually twelve to twenty-one months. It is one of the few genuinely powerful tools available to someone carrying card debt. It is also easy to use badly.
The arithmetic when it works
Take $5,000 at 24.99% APR and a plan to pay $250 a month. Staying put, you clear it in 27 months and pay $1,535 in interest.
Transfer it to an eighteen month 0% card with a 3% transfer fee. The fee is $150, added to your balance up front. At $250 a month you pay off $5,150 in 21 months, entirely inside the promotional window, and your total interest is zero.
You paid $150 to avoid $1,535. That is the entire case for a balance transfer, and when it lands like this it is close to unbeatable.
The three ways it goes wrong
You do not finish before the promo ends. This is the big one. Whatever balance remains starts accruing at the new card's regular APR, which is often no better than the card you left. Divide your balance plus the fee by the number of promotional months. If that monthly figure is more than you can genuinely pay, the transfer is a delay, not a fix.
You keep spending on the old card. Transferring leaves the original card at a zero balance and full available credit. If it fills back up, you now have two debts instead of one.
You assume purchases are also 0%. On many cards the promotional rate applies only to the transferred balance. New purchases can accrue interest from day one.
Run this before you apply: (balance + transfer fee) divided by promotional months. If you cannot pay that number every month without fail, look at a fixed-rate consolidation loan instead. A slightly higher rate with a guaranteed term beats a 0% offer you cannot finish.
What applying costs you
A transfer means a new card, which means a hard inquiry on your credit report and a small temporary dip in your score. It also lowers your overall credit utilisation by adding available credit, which tends to help. For most people the net effect is mildly positive within a few months.
You generally cannot transfer a balance between two cards from the same issuer, and your approved transfer limit may be lower than the debt you wanted to move.
The short version
- Transfer fees run about 3% to 5%, added to your balance immediately.
- Worth it when you can clear the full balance inside the promotional window.
- Do the division first: (balance + fee) divided by promo months.
- Close nothing, but stop spending on the emptied card.
Common questions
Does a balance transfer hurt your credit score?
Slightly and briefly, from the hard inquiry. It usually helps within a few months because the new account raises your total available credit and lowers your utilisation ratio.
What happens if I do not pay it off before the 0% ends?
The remaining balance starts accruing at the card's standard APR. You keep the interest you already saved, but the rest is charged at normal rates from that point on.
Can I transfer a balance between cards from the same bank?
Almost never. Issuers exclude their own cards, since they would be moving your debt to a rate that earns them nothing.