Is a balance transfer worth it? Run these numbers first
A worked $6,000 example, the break-even, and the four situations where it backfires.
On this page
A balance transfer moves debt from a card charging interest to one offering 0% for a promotional period, in exchange for an upfront fee, usually 3% to 5%. It works when the interest you avoid exceeds the fee. That is an arithmetic question, not a judgement call.
A worked example
Take $6,000 on a card at 22.99% APR, versus transferring it to a 0% card for 15 months with a 3% fee.
Paying $412 a month clears the transferred balance in 15 months for a total of $6,180. Paying that same $412 on the original card takes 18 months and costs $7,103, because $1,103 goes to interest. The transfer saves about $923.
When it does not work
- You will not clear it in the promo window. Whatever remains starts accruing at the new card standard rate. Divide the balance by the number of promotional months; if you cannot pay that, the maths changes.
- You keep spending on the old card. Transferring debt and refilling the original balance leaves you with two debts.
- The fee is 5% and the promo is short. A 5% fee on a 12-month promo is a high bar for a moderate APR to clear.
- New purchases on the transfer card. These may not get the 0% rate, and payment allocation rules can leave them accruing interest.
The break-even is roughly: transferring is worth it if the interest you would otherwise pay during the promotional period exceeds the fee. At a 3% fee, that is usually true above about 12% APR if you clear the balance in time.
Do this before applying
- Work out the monthly payment that clears the balance inside the promotional period. If it is unaffordable, the transfer is not the fix.
- Check the fee, the promotional length, and the rate afterwards.
- Set autopay for that fixed amount, not the minimum. See why the minimum payment is so expensive.
- Stop using the old card, but do not rush to close it, since that raises utilization.
The break-even, stated as a rule you can apply
The transfer is worth it when interest avoided exceeds the fee. Roughly, the interest you would pay over the promotional period is the balance multiplied by the APR multiplied by the fraction of a year, and against a 3% fee the crossover arrives quickly.
| Current APR | Interest avoided over 15 months on $6,000 (approx) | Against a 3% fee ($180) |
|---|---|---|
| 10% | About $400 | Worth it if you clear it in time |
| 18% | About $750 | Clearly worth it |
| 23% | About $1,000 | Clearly worth it |
| 29% | About $1,300 | Clearly worth it |
These are approximations on a declining balance, which is why they are smaller than APR multiplied by the full balance. The conclusion holds across the range: at a 3% fee, almost any card APR clears the bar provided the balance is repaid inside the promotional window. That condition, not the arithmetic, is what decides most cases.
Work out the payment first, then decide
Divide the transferred amount, including the fee, by the number of promotional months. That is the payment required. If it is not affordable, a transfer converts a manageable expensive debt into an unmanageable cheap one that reverts to expensive.
On a $6,000 transfer over 15 months, the required payment is about $412 a month. If your budget supports $250, the promotional period will end with roughly $2,400 outstanding at the card standard rate.
Being partway through is not a disaster, and you will still have saved interest. But plan for it deliberately rather than discovering it in month 16.
What happens to your credit score
- At application: a hard inquiry, worth a few points. See how inquiries work.
- Immediately after: total available credit rises, which usually lowers overall utilization and helps.
- But: the new card may sit near its own limit, and per-card utilization is also considered.
- Over time: as the balance falls, both measures improve. Net effect is typically positive after a short dip.
Deferred interest is a different product
Some retail financing offers look like 0% but are structured as deferred interest: interest accrues in the background from day one and is charged retroactively in full if any balance remains at the deadline. A genuine 0% balance transfer does not do this. The distinction is worth confirming in the terms, because the consequences of missing the deadline are completely different.
Frequently asked questions
Does a balance transfer hurt my credit score?
The application adds a hard inquiry, and the new limit usually lowers overall utilization, which helps. Net effect is often mildly positive after a short dip.
Can I transfer between cards from the same issuer?
Usually not. Most issuers do not allow transfers between their own cards.
What happens at the end of the promo?
Any remaining balance starts accruing at the standard rate. There is no retroactive interest on a genuine 0% offer, unlike deferred-interest financing, which is a different product.
Is the fee ever worth it on a small balance?
Less often. Fixed fees weigh more heavily on small balances, and a few months of aggressive repayment may cost less than the fee.
How long does a balance transfer take?
Often a few days to a couple of weeks. Keep paying the old card until the transfer shows as completed, because a missed payment during the gap is reportable.
Can I transfer more than one balance?
Usually yes, up to the new card limit, which may be lower than the total you want to move.
Does the fee get added to the transferred balance?
Typically yes, so a $6,000 transfer with a 3% fee becomes $6,180 owed. Include it when working out the monthly payment.
Should I close the old card afterwards?
Usually not immediately. Closing it removes its limit and can raise utilization. Leave it open with no balance unless it carries a fee.
Written by
Teja PagidimarriTeja Pagidimarri built 43dots to answer money questions with numbers you can check. He is a software developer, not a licensed financial advisor, so every guide here is built the way an engineer would: figures pulled from the primary source, math shown in the open, and the calculators built from the actual published formulas.
Every figure on this page was checked against the primary source linked beside it. Drafting is AI-assisted; the research, the numbers, and the final edit are mine. See our editorial policy and corrections. This is general information, not personalized financial advice.
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