Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Net savings from transferring
$2,100
Interest if you stay put
$2,600
Transfer fee
$210
Balance left when promo ends
$1,810
Interest after promo ends
$290
Payment needed to finish in promo
$401
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How to use this
- 1Enter balance to transfer ($).
- 2Enter current apr (%).
- 3Enter transfer fee (%).
- 4Enter 0% promo length (months).
- 5Enter go-to apr after promo (%).
- 6Enter monthly payment ($).
- 7Read your net savings from transferring on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
A 0% balance transfer only saves money if the interest you avoid exceeds the transfer fee, and if you clear enough of the balance before the promotional rate expires. Most people model the first half and skip the second, which is how a 'free' transfer turns into a leftover balance at a go-to rate that can be higher than the card they left. This calculator compares staying put against transferring: it charges the fee up front, applies 0% during the promo, then applies the go-to APR to whatever remains, and reports net savings plus the monthly payment you would need to finish inside the promo window.
Worked example
Using the values the calculator loads with:
Inputs
- Balance to transfer: 7000 $
- Current APR: 23.9 %
- Transfer fee: 3 %
- 0% promo length: 18 months
- Go-to APR after promo: 26.9 %
- Monthly payment: 300 $
Results
- Net savings from transferring: $2,100
- Interest if you stay put: $2,600
- Transfer fee: $210
- Balance left when promo ends: $1,810
- Interest after promo ends: $290
- Payment needed to finish in promo: $401
What each field means
Inputs
- Balance to transfer ($)
- The balance to transfer used in the calculation, measured in $. Starts at 7000 $ so you have a working example on load. Accepted range: 0–200000 $.
- Current APR (%)
- The current apr used in the calculation, measured in %. Starts at 23.9 % so you have a working example on load. Accepted range: 0–40 %.
- Transfer fee (%)
- The transfer fee used in the calculation, measured in %. Starts at 3 % so you have a working example on load. Accepted range: 0–10 %.
- 0% promo length (months)
- The 0% promo length used in the calculation, measured in months. Starts at 18 months so you have a working example on load. Accepted range: 0–36 months.
- Go-to APR after promo (%)
- The go-to apr after promo used in the calculation, measured in %. Starts at 26.9 % so you have a working example on load. Accepted range: 0–40 %.
- Monthly payment ($)
- The monthly payment used in the calculation, measured in $. Starts at 300 $ so you have a working example on load. Accepted range: 0–20000 $.
Results
- Net savings from transferring
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Interest if you stay put
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Transfer fee
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Balance left when promo ends
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Interest after promo ends
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Payment needed to finish in promo
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Is the transfer fee charged on day one?
Yes, almost always. It is added to the transferred balance immediately, which is why it is modelled up front here.
Does a transfer hurt my credit score?
The new account adds a hard inquiry and lowers average account age, usually a small short-term effect. Lower utilization often helps more over time. Effects vary.
Can I transfer again later?
Sometimes, but repeat transfers stack fees and issuers often decline transfers between their own cards. Plan to finish inside one window.
What if I keep spending on the old card?
Then you have two balances. The savings shown here assume the transferred balance is paid down and the old card is not re-run.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Balance Transfer Savings Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/balance-transfer-savings-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/balance-transfer-savings-calculator" target="_blank" rel="noopener">Balance Transfer Savings Calculator — RevenueLab</a> (2026).</p>
Source: [Balance Transfer Savings Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/balance-transfer-savings-calculator) (2026).