How Does a Balance Transfer Work? A Beginner's Guide

A balance transfer moves debt from one or more credit cards onto another card, usually one with a low or 0% promotional rate for a set number of months. So how does a balance transfer work in practice? The transferred balance moves to the new card, usually with a transfer fee. During a 0% promotional APR period, payments reduce the transferred balance without promotional interest, but other balances or transactions may accrue interest.

What a balance transfer really is

A balance transfer swaps who you owe for the same debt. The total you owe does not shrink. What changes is the interest rate on that debt for a while, and sometimes the number of cards you are keeping track of. If the old card charges a high rate and the new one charges 0% for a promotional period, much more of each payment goes to the balance itself.

A 0 interest balance transfer does not mean the interest is gone for good. The 0% rate has an end date. Whatever balance is left after that date starts collecting interest at the card's regular rate, which is often high. The whole strategy works or fails on what happens before that date.

The steps, from start to finish

1. Approval for a card that allows transfers. The card company checks your credit and sets a credit limit. That limit caps how much you can move, and it can be lower than your total debt.
2. The transfer request. You give the old card's account number and the amount to move. This often happens during the application or soon after, in the online account.
3. The new card pays the old one. This can take several days or a couple of weeks. Until the old card shows the balance as paid, its minimum payment is still due, so a missed payment there still counts as late.
4. The fee is added. The transfer fee is usually a percentage of the amount moved, and it lands on the new balance right away.
5. The promo clock runs. Depending on the terms, the 0% period may start when the account opens or when the transfer posts. Monthly minimum payments still apply the whole time.
6. The promo ends. Any remaining balance moves to the card's regular rate from that point on.

The numbers that decide what it really costs

• The transfer fee. Usually a few percent of the amount moved, charged up front. Some offers have no fee, which changes the math; here is how a 0% purchase card compares on fees.
• The length of the promo. The number of months at 0% sets the monthly payment needed to clear the balance in time. Shorter promos mean bigger payments.
• The rate after the promo. This is what any leftover balance costs once the promo ends. It matters most if the debt is too big to clear in time.
• The rate on new purchases. On many cards, new purchases do not get the 0% rate. Mixing new spending with a transferred balance makes the debt harder to track and can cost interest.

A worked example with real math

Example: Say you owe $5,000 on a card charging 24% a year, which is about 2% a month. One option is to keep the debt there and pay it off over 12 months. The other is a balance transfer to a card with 0% for 12 months and a 3% transfer fee. These numbers are made up to keep the math simple.

• Staying put: clearing $5,000 at 2% a month in 12 months takes about $472.80 a month. 12 × $472.80 = $5,673.60 paid in total, so about $673.60 goes to interest.
• Transferring: the fee is 3% × $5,000 = $150, so the new balance is $5,150. Clearing it in 12 months takes $5,150 ÷ 12 = about $429.17 a month. Total paid is $5,150, and the only cost is the $150 fee.
• The difference: $673.60 minus $150 = about $523.60 kept in your pocket, plus a lower monthly payment.

Now the other side. If you only paid $300 a month on the transferred balance, 12 × $300 = $3,600 would be paid by the end of the promo. That leaves $5,150 minus $3,600 = $1,550 still owed, now at the regular rate. The transfer still helped, but it did not finish the job. You can run your own numbers in our balance transfer calculator to see the monthly payment your promo length needs.

Where balance transfers tend to go wrong

• Using the old card again. The old card now shows a zero balance and its full limit. Charging it back up leaves you with two debts instead of one.
• No plan for the end date. When I go through these numbers with people, the fee is rarely the problem. The end date usually is. Dividing the balance by the promo months gives the payment that clears it in time.
• Late payments. On some cards a late payment can end the promo rate early or add a penalty rate. The card's terms spell this out.
• How payments are applied. To the best of our knowledge, payments above the minimum generally go to the highest rate balance first, but the details depend on the card. The CFPB (consumerfinance.gov) explains credit card payment rules in plain language.
• Your credit score. A new account means a credit check and a new limit, and moving balances changes how much of your limits you use. Here is more on how credit utilization affects your score.

Weighing it against other ways to pay down debt

A balance transfer tends to work out when the debt can realistically be cleared within the promo period, the fee is smaller than the interest you would otherwise pay, and new spending stays off the cards. It tends to work less well when the balance is large compared to your income, when approval brings a limit too small to matter, or when the promo ends with most of the debt still there.

Other routes have their own trade offs. A fixed rate loan gives a set payment and end date but usually charges some interest the whole time; this comparison of a balance transfer versus a personal loan walks through both. For a closer look at when the fee pays for itself, see the real math on 0% cards.

FAQ

Does a balance transfer hurt your credit?

It can have mixed effects. A new card usually brings a credit check and a newer average account age, which can lower a score a little at first. A higher total credit limit can lower your utilization, which often helps. How it nets out depends on your whole credit file.

Can I move a balance between two cards from the same company?

To the best of our knowledge, most card companies do not allow transfers between two of their own cards. Transfers usually go from a card at one company to a card at another. The offer's terms say what is allowed.

What happens if the balance is not paid off before the 0% period ends?

The remaining balance starts collecting interest at the card's regular rate from that point on. In the example above, $1,550 would be left at 24%. The months you paid at 0% still saved interest, but the leftover balance now costs money every month.

How long does a balance transfer take?

It often takes several days to a couple of weeks for the new card to pay the old one. During that time the old card's minimum payment is still due, so it is worth watching both accounts until the old balance shows as paid.

Is a balance transfer the same as debt consolidation?

It is one form of it. A balance transfer combines card debt onto one card at a promo rate, while other forms of consolidation use a loan with a fixed rate and term. Each has different costs and risks, so the numbers for your own debt are what decide the trade off.