Does a 0% Balance Transfer Actually Save You Money?
The fee is not the thing to worry about. Moving $8,000 costs $240 at 3%. against $1,855 of interest you would have paid by staying put. What decides whether a transfer works is whether you clear it before the offer ends. On an 18-month deal that means $458 a month, and almost nobody works that number out first.
The comparison that actually matters
People fixate on the transfer fee. It is almost always the wrong thing to worry about.
$8,000 moved to a 0% card with a 3% fee:
| Cost | |
|---|---|
| The transfer fee | $240 |
| Staying put at 22% over the same 18 months | $1,855 |
The fee is about an eighth of what doing nothing costs. On high-rate debt, the fee is rarely the deciding factor.
What decides it is something else entirely.
The number to work out before you apply
The balance plus the fee, divided by the promotional months.
$8,000 + $240 fee = $8,240, over 18 months = $458 a month.
That is the payment that clears the whole thing while it is still charging nothing. If you can manage it, the transfer costs you exactly $240 and not a penny more.
If you cannot, the deal still probably works - but you need to know what happens next, because the marketing will not tell you.
What falling short actually costs
Here is the same $8,000 transfer at three different payments, from the balance transfer calculator:
| Paying | Left when the offer ends | Interest after | Total cost | Staying put would cost |
|---|---|---|---|---|
| $458 | $0 | $0 | $240 | $1,675 |
| $400 | $1,040 | $36 | $276 | $1,855 |
| $300 | $2,840 | $308 | $548 | $2,165 |
Two things worth noticing.
Falling a bit short is not a disaster. Paying $400 instead of $458 leaves $1,040 owing when the rate kicks in - but by then the balance is small, so it only costs about $36 extra. Total cost $276 against $240.
All three still beat staying put, and comfortably. Even the $300 payment costs $548 against $2,165. The transfer is doing real work in every case.
The danger is not being slightly short. It is being far short - transferring a large balance, paying a token amount, and arriving at the end of the offer with most of it intact and a high rate switching on.
The trap nobody warns you about
The transfer empties your old card. You now have a card with a full limit and a zero balance sitting in your wallet.
That is the actual risk, and it is behavioural rather than mathematical. People who end up worse off after a balance transfer almost always got there the same way: they paid down the transferred balance while quietly rebuilding the original one. Now they have two debts where they had one.
If you do a transfer, decide in advance what happens to the old card. Not “I’ll be careful”. an actual decision. Freeze it, put it in a drawer, hand it to someone. The arithmetic on this page assumes the old card stays empty, and if it does not, none of it holds.
Do not close it, though. Closing a card removes its limit from your total available credit, which raises your utilisation and can knock your score - see the credit utilisation calculator for how that works.
What to check on the offer itself
The go-to rate. What it charges once the offer ends. Often as high as the card you left.
Whether the offer applies to purchases too. Sometimes 0% covers transfers only, and anything you buy starts charging interest immediately - sometimes with payments applied to the cheapest balance first.
The transfer window. Many offers only give the promotional rate on balances moved within the first 60 days.
Whether there is a fee cap. Some cards cap the fee, which matters on larger balances.
Before you apply
- Work out the clearing payment. Balance plus fee, divided by promotional months. If that number is impossible, the offer is not right for this balance.
- Compare the fee against staying put. On high-rate debt it is usually not close.
- Decide what happens to the old card. Before, not after.
- Find the go-to rate, so the end of the offer is not a surprise.
Run your own balance through the balance transfer calculator - it leads with the payment that clears it in time, and shows what the leftover costs when the rate switches on.
Common questions about balance transfer
Is the balance transfer fee worth paying?
Usually, and by a wide margin. A 3% fee on $8,000 is $240. Carrying that same balance at 22% for 18 months costs around $1,855 in interest. The fee is the small number in that comparison - the risk sits elsewhere.
What payment do I need to clear it in time?
The balance plus the fee, divided by the number of promotional months. On $8,000 with a 3% fee over 18 months that is $8,240 ÷ 18 = $458 a month. Work this out before you apply, not after.
What happens if I do not clear it in time?
Whatever is left starts charging the go-to rate, which is often as high as the card you left. Paying $400 rather than $458 leaves $1,040 when the offer ends - but that only costs about $36 more, because the balance is small by then. Falling far short is what hurts.
Does a balance transfer hurt my credit score?
A new application causes a small, temporary dip. But the new card also adds available credit, which usually lowers your overall utilisation - and that tends to help. Keeping the old card open rather than closing it protects that benefit.
What is the real risk?
Using the freed-up old card again. The transfer empties it, and an empty card with a limit is an invitation. People who end up worse off almost always got there by rebuilding the original balance while paying off the transferred one.