Balance Transfer Calculator
Balance & offer
Your result will appear here
Fill in the fields on the left and this updates as you type.
Know what this estimate is based on
- Jurisdiction
- United States card and lending practice
- Scope and limitations
- Educational estimate only. Your issuer sets the minimum-payment formula, how a payment is allocated across balances, when interest is charged, and any fees or promotional terms — check your cardholder agreement for the figures that bind.
- Source links checked
- Jul 30, 2026
Built and regression-tested by Smart Tools Lab. It has not been individually reviewed by a licensed financial, tax, or legal professional.
How to use
- 01
Enter the balance you would move and the APR you are paying on it now.
- 02
Enter the offer's promotional APR — usually 0% — and how long that window lasts. Fifteen, 18 and 21 months are the common U.S. terms, and the length is what decides the whole question; your offer letter has the exact one.
- 03
Enter the transfer fee, typically 3% to 5% of the amount moved, and what you can pay each month. A transfer only saves money if the balance actually falls during the promo.
- 04
Open Advanced options if the rate after the promo is not the rate you pay now. It only bites on a balance that has not cleared by the time the window closes.
- 05
Read the net saving and the side-by-side table, then check whether any of your payoff falls after the promo ends — those months are charged at the revert rate.
Formula
A transfer moves the balance to a new card at a promotional rate for a fixed number of months, in exchange for a fee charged up front and added to the transferred balance. The tool simulates both paths month by month at your payment. Staying: the balance accrues at your current APR until it clears. Transferring: the balance plus the fee accrues at the promotional rate for the promo months, then at the revert rate for however long is left. Net saving = interest if you stay - (fee + interest after transferring). Because the promo has an end date, any months of payoff that fall past it are charged at the revert rate — the tool names that tail in months and dollars, since it is what decides whether an offer is worth taking.
Example
Inputs: a $6,000 balance at 22% APR, an offer of 0% for 15 months with a 3% transfer fee reverting to 22%, and $300 a month. Step 1 — Size the fee. $6,000 x 3% = $180. It is added to the balance, so you transfer $6,180. Step 2 — Price staying put. At 22% paying $300 a month the card clears in 2 years 2 months and costs $1,543 in interest. Step 3 — Price transferring. During the 15-month promo, 0% means every dollar of the $300 goes to principal: $4,500 comes off, leaving $1,680. From month 16 the revert rate applies, and the remainder takes 6 more months at 22%, costing $109. Total time: 1 year 9 months. Step 4 — Compare. Staying costs $1,543 of interest. Transferring costs $180 of fee plus $109 of interest, $289 in all. Result: a net saving of $1,254, and the card clears five months sooner. Note the tail — 6 of those 21 months fall after the promo ends. Paying $412 a month instead would clear the balance and the fee inside the 15-month window, which is the only way a 0% offer costs nothing beyond its fee.
Definitions
- Balance transfer
- Moving debt from one card to another, normally to take a lower promotional rate for a fixed period.
- Promotional APR
- The temporary rate on the transferred balance, often 0%. It applies for a set number of months and then reverts.
- Promo window
- How long the promotional rate lasts — typically 12 to 21 months. The single most important number in the offer after the fee.
- Revert rate
- The APR that applies once the promo ends, charged on whatever balance remains. Often as high as the card the balance came from.
- Transfer fee
- A one-off charge for moving the balance, usually 3% to 5% of the amount. It is normally added to the new balance, so it accrues interest too.
- Deferred interest
- A promotion that waives interest only conditionally: if any balance remains at the deadline, every waived dollar is charged retroactively.
- Break-even
- The point at which the interest a transfer saves exceeds the fee it costs. Below it, staying put is cheaper.
- Hard inquiry
- The credit check an application triggers. It costs a few points and fades within a year, though it stays on the report for two.
- Credit limit
- The maximum the new issuer will let you carry — and therefore the ceiling on how much you can transfer.
- Utilization
- Balances divided by limits. A transfer usually improves it by adding a limit without adding debt.
- Payment allocation
- How an issuer applies your payment. Anything above the minimum must go to the highest-APR balance first, which matters when a promo balance and a purchase balance share a card.
- Offer expiry
- The deadline for completing the transfer after opening the account, commonly 60 to 120 days. Missing it can forfeit the promotional rate.
Good to know
What a balance transfer actually buys you
A balance transfer moves debt you already owe from a card charging a high rate onto a different card offering a low promotional rate, usually zero percent, for a fixed number of months. Nothing about the amount owed changes at the moment of transfer except that interest stops, or nearly stops, accumulating. The principal travels with you. What you are buying is time: a window during which every unit you pay lands almost entirely on principal instead of being split between principal and interest. On the default scenario, a 100,000 balance at 22 percent that would otherwise bleed roughly 1,833 in interest in the very first month alone stops doing so the instant it sits on a zero percent card. That paused interest is the whole point. But the offer is not free. The new card charges a transfer fee, here 3 percent, added to the moved balance on day one. So the honest question is never simply whether zero percent beats 22 percent, which it obviously does, but whether the interest you avoid is larger than the upfront fee you pay to avoid it. This tool answers exactly that by simulating both paths at the identical monthly payment and reporting the net result. Treat the transfer as a tool for breaking the interest cycle on a balance you are already committed to clearing, not as new spending power. The card has not forgiven anything; it has rented you a quiet period, and the rent is the fee. Whether that rent is worth paying is a number, not a slogan.
The fee-versus-interest break-even, in plain terms
The single calculation that decides whether a transfer is worth doing is a subtraction. On one side sits the interest you would pay by staying put; on the other sits the fee plus any interest you would still pay after transferring. The tool computes the first by simulating payoff of your current balance at your current rate, and the second by simulating payoff of your balance plus the fee at the promotional rate. The net saving is stay-interest minus the sum of fee and transfer-interest. When that result is positive, the transfer keeps money in your pocket; when negative, the fee has eaten more than the interest you saved. With the default inputs the stay path costs about 20,432 in interest, while the transfer path costs only the 3,000 fee because the promotional rate is zero, leaving a net saving near 17,432. The break-even point is the fee level at which those two sides are equal. Because the promotional rate here is zero, transfer-interest is essentially nil, so the transfer keeps winning until the fee alone matches the interest avoided. On these numbers that tipping point sits around a 20 percent fee, far above any real-world offer, which is why a genuine zero percent transfer on a high-rate balance is so often worthwhile. The lesson is structural: a transfer is attractive when the rate gap is wide and the balance lingers long enough to accrue real interest, and unattractive when the gap is narrow, the fee is steep, or the balance is so small it would clear cheaply anyway.
Why the same monthly payment is the only fair comparison
It is tempting to compare a transfer by imagining you pay the minimum on the old card but throw everything at the new one. That is not a comparison; it is two different plans, and it flatters the transfer for reasons that have nothing to do with the rate. This tool removes that distortion by holding the monthly payment identical on both paths. The default 6,000 per month is applied to the stay scenario and the transfer scenario alike, so the only things that differ are the interest rate and the fee. That discipline matters because payment size, not rate, is usually the biggest driver of how much interest a debt accrues. A bigger payment clears principal faster, which starves interest on either card. If you let the payment float, you could make almost any transfer look good or bad at will. By fixing it, the tool isolates the real question: given that you will commit the same money each month, does swapping the rate and paying the fee leave you better off. The honest way to read the result is therefore to first decide what you can sustainably pay every month, enter that figure, and keep it constant. If you can genuinely afford more after transferring, model that higher figure on both sides to see its effect, but never compare a high transfer payment against a low stay payment. The apples-to-apples payment is what makes the net saving trustworthy, and it is the assumption most casual transfer comparisons quietly violate.
Can you clear the balance inside the promo window?
A promotional rate is not permanent. It lasts a set number of months, and the entire value of a transfer depends on whether you can extinguish the balance before that window closes. The tool's payoff simulation tells you how many months your chosen payment needs. With the defaults, the moved balance is 103,000 including the fee, and at 6,000 per month a zero percent balance falls by exactly 6,000 each month, clearing in about eighteen months. If your offer's window is eighteen months or longer, the whole balance dies inside the promotional period and you pay only the fee. If the window is shorter, say twelve months, the same balance would need roughly 8,583 per month to finish in time, and any amount left when the clock runs out reverts to a standard rate. The arithmetic for an interest-free transfer is refreshingly simple: required monthly payment equals the balance plus fee divided by the number of promotional months. Compare that figure honestly against what you can actually pay. The most common transfer mistake is treating the headline zero percent as the prize while ignoring the deadline attached to it. A transfer you cannot finish in time is not a zero percent loan; it is a fee-plus-deferred-interest arrangement wearing a zero percent label. Before committing, divide your balance by the months on offer, confirm you can sustain that payment through job changes and emergencies, and leave yourself a cushion. The window is the constraint that turns a good offer into a real saving rather than a deferred problem.
What happens when the promo rate ends
Every promotional rate has a morning after. Whatever balance remains when the introductory period expires stops being interest-free and begins accruing at the card's standard, or go-to, rate, which is frequently as high as or higher than the rate you transferred away from. This is where transfers quietly fail. Suppose you move the default 100,000 plus fee but only pay enough to clear part of it before the window shuts; the leftover lands on a rate that can rival the original 22 percent, and the interest clock you paused restarts on the remaining sum. The fee you paid to escape interest now buys you nothing on that residual balance. The tool's default scenario is deliberately clean because the payment clears the balance inside the implied window, so no balance survives to face the go-to rate. Real offers are messier, and the disciplined approach is to plan for the balance to hit zero with months to spare, not to bet on finishing exactly at the deadline. Read the card's terms for the post-promotional rate before transferring, because that number is what governs any slippage. Resist the instinct to relax once the high-rate pressure lifts; the absence of monthly interest can make a balance feel smaller and less urgent than it is, and that comfort is precisely what leaves a stub to revert. A transfer rewards the borrower who treats the promotional window as a hard countdown to zero and penalizes the one who treats it as a holiday. Plan the payoff, then beat it.
The deferred-interest trap to watch for
Not every zero percent offer works the same way, and the most dangerous variety is deferred interest rather than waived interest. Under a true waived-interest promotion, the interest that would have accrued during the window is simply forgiven, and if a balance remains afterward, only that remaining balance accrues interest going forward. Under a deferred-interest promotion, interest is silently calculated and stored in the background from day one, and it is only cancelled if you clear the entire balance before the window ends. Miss the deadline by a single unit or a single day, and the whole stack of back-interest, computed on the original balance for the full promotional period, is added at once. The difference is enormous. On the default 103,000 balance, eighteen months of background interest at a high rate could be a five-figure charge that lands retroactively, turning a seemingly cheap zero percent deal into one of the most expensive ways to carry debt. This tool models a straightforward promotional rate and does not assume a deferred-interest structure, so if your offer carries one, the real downside of missing the window is far worse than the simulation's clean numbers suggest. Protect yourself by reading whether the offer says interest is waived or deferred, treating any deferred-interest deal as all-or-nothing, and aiming to clear the balance well before the deadline rather than at it. The safest deferred-interest plan finishes a month or two early on purpose. When in doubt, assume the harsher structure and pay as though every remaining unit at the deadline could trigger the full retroactive charge.
Reading the net saving, fee, and interest figures
The tool returns four numbers worth understanding individually rather than glancing at the headline alone. The net saving is the bottom line: stay-interest minus the sum of fee and transfer-interest, positive when transferring helps and negative when it hurts. With the defaults this is about 17,432 in your favour. The transfer fee, here 3,000, is the upfront, certain cost you accept in exchange for the rate cut; it is the same whether or not the plan goes perfectly. Interest if you stay, about 20,432 on the defaults, is the interest your current card would charge over the full payoff at your current rate and payment. Interest after transfer, zero in the default case, is what the promotional card charges on the moved balance plus fee. Reading them together tells a fuller story than the headline. A large positive saving driven mostly by a high stay-interest figure means your current rate is genuinely punishing and almost any reasonable transfer helps. A thin saving means the fee is consuming most of the benefit, and small changes to fee or payment could flip the decision, so test them. If transfer-interest is non-zero, your promotional rate is above zero or the balance does not clear in the simulation, and you should investigate why before trusting the result. The figures are not just a verdict; they are a diagnosis. Adjust the inputs and watch which number moves to learn whether your decision rests on a wide rate gap, a forgiving fee, or a payment large enough to finish quickly.
When a transfer is the wrong move
A transfer is a tool, and like any tool it is wrong for some jobs. It disappoints when the fee is large relative to a small or short-lived balance: if you would clear the debt in a few months anyway, the interest you avoid may be smaller than the fee you pay, and the net saving turns negative. It disappoints when the rate gap is narrow, because a promotional rate only a few points below your current one leaves little interest to save against the fee. It disappoints most of all when you cannot realistically clear the balance inside the window, since the leftover reverts to a high rate and, under a deferred-interest structure, can trigger retroactive charges that dwarf the fee. There is also a behavioural failure mode the arithmetic cannot capture: a transfer empties your old card's balance, and if the temptation to spend on that newly available limit is real, the transfer can leave you with two balances instead of one. The tool will tell you when the fee outweighs the interest saved, but it cannot tell you whether you will keep paying the same amount or keep the old card idle. Before transferring, confirm three things the calculator cannot: that you can sustain the payment for the whole window, that you will not re-borrow on the cleared card, and that your offer is genuine waived interest rather than the deferred kind. If any of those is shaky, the clean positive number on screen may overstate the real outcome. A negative net saving is a clear no; a thin positive one deserves a second look at your own discipline.
How fee size and rate gap drive the decision
Two levers move the transfer verdict more than any others: the size of the fee and the width of the rate gap. The fee is a fixed percentage of the balance, charged once and added to what you owe, so a 3 percent fee on 100,000 is 3,000 regardless of how the rest of the plan unfolds. It is the certain cost. The rate gap, the distance between your current rate and the promotional rate, determines how much interest you stand to avoid, but only in combination with how long the balance lingers. A wide gap on a balance that clears slowly avoids a great deal of interest; the same gap on a balance that clears in two months avoids almost nothing. This is why the break-even fee on the default scenario sits so high, near 20 percent: the 22-point gap against a zero percent promo, applied to a balance that takes well over a year to clear at the chosen payment, accumulates roughly 20,432 in avoidable interest, and the fee would have to be enormous to overtake it. Flip the inputs and the logic reverses. Narrow the gap by entering a higher promotional rate and the avoided interest shrinks toward the fee. Raise the fee and the certain cost climbs toward the avoided interest. Shrink the balance or raise the payment so the debt clears quickly, and there is simply less interest to avoid. The disciplined way to use the tool is to vary these two inputs around your real offer and watch the net saving cross zero, which shows you exactly how much margin your decision actually has.
Frequently asked questions
Is a balance transfer worth the fee?
Only if the interest it saves exceeds the fee. On $6,000 at 22% paying $300 a month, a 3% fee costs $180 and saves about $1,254 — clearly worth it. At a small balance, a low rate, or a fast payoff, the fee can be larger than the interest avoided.
What happens when the 0% period ends?
Whatever is left starts accruing at the revert rate, which is often as high as the card you transferred from. This calculator charges those months explicitly rather than pretending the promo lasts forever.
What is deferred interest, and is it the same thing?
No, and the difference is expensive. A true 0% APR offer charges nothing during the promo and normal interest afterwards. A deferred-interest offer charges all the interest it waived, retroactively, if any balance remains at the deadline.
Does a balance transfer hurt my credit score?
Briefly. The application adds a hard inquiry and lowers your average account age. But the new card's limit raises your total available credit, so overall utilization usually falls — which typically helps within a few months.
Can I transfer more than the new card's limit?
No. Issuers approve a transfer up to your new credit limit, and often only up to a portion of it. If your balance is larger, you can move part of it and keep paying the rest on the original card.
Can I transfer a balance between cards from the same bank?
Generally not. Almost all issuers prohibit transfers between their own accounts, so a transfer means moving to a different bank.
Do new purchases on the transfer card get 0% too?
Sometimes, but not always — many offers apply the promo rate to the transferred balance only, and charge the standard APR on new purchases from day one. Using the card for spending while a transfer sits on it is usually a mistake.
How long do I have to make the transfer?
Most offers require the transfer within 60 to 120 days of opening the account, and some price the fee higher after an initial window. Missing the deadline can forfeit the promotional rate entirely.
What payment clears the balance inside the promo?
The transferred amount plus the fee, divided by the number of promo months. The calculator shows this figure — it is the only payment at which a 0% offer truly costs nothing but the fee.
Should I close the old card after transferring?
Usually not. Closing it removes that limit from your utilization calculation and eventually shortens your credit history. Leaving it open with a zero balance is normally better for your score.
Do I still have to make minimum payments during the promo?
Yes. A 0% rate does not mean no payment — you owe at least the minimum every month. One late payment costs you a late fee and a mark on your report, but federal rules protect the promotional rate itself until a minimum goes 60 days past due — at which point the issuer may end the promo and apply a penalty rate.
Is a personal loan better than a transfer?
For a larger balance or a longer payoff, often yes: a fixed-rate loan has a defined end date and no cliff. For a balance you can clear within the promo window, a 0% transfer is almost always cheaper. The Debt Consolidation Calculator prices the alternative.