How is credit card interest calculated?

How is Credit Card Interest Calculated

If you’re like most people repairing their credit card debt, your credit card’s annual interest rate is a mystery to you. You might even avoid thinking about it or looking at it, because it’s such a large number. Interest rates can make it difficult to get out of debt quickly, because you’re working against a large percentage—as much as 16% or even 20% annual interest.

Credit card interest is calculated using a complicated formula that can be confusing to many people. So it often remains a puzzle to borrowers. But it’s important to understand the basics of credit card interest, because it will help you to repair your credit card debt quicker—and to be a smarter credit card user. Here’s how credit card interest works.

How Is Credit Card Interest Calculated?

credit card interest calculation

If you’ve watched your interest rate closely, you may have noticed that it has changed since you first opened your credit card. Many credit cards offer a low introductory interest rate that increases after the period is over. But even after that, your annual interest rate will often go up and down. That can be confusing, and even a bit unsettling.

Your interest rate changes

The first thing you should understand is that your credit card uses a variable interest rate. That means that the interest rate can change over time. A variable rate is tied to a base index—usually the U.S. prime rate. As the U.S. prime rate goes up or down, so will your credit card’s interest rate.

Right now, the U.S. prime rate is 4.25%. But your credit card’s interest rate is probably closer to 18.25%, or even more. That’s because credit card companies charge an additional amount above the U.S. prime rate—perhaps 14%, but it varies from card to card. So your total interest rate will be closer to 18.25%, annually. If the U.S. prime rate raises or lowers, your annual interest rate will also go up or down by the same amount.

The factors that influence the U.S. prime rate are reviewed every six weeks. The prime rate could stay the same for years, or it could change every six weeks. It all depends on current federal economic conditions and forecasts.

Your interest rate is annual

It’s also important to understand that your credit card’s interest rate is an annual rate. So if your annual rate is 18.25%, that amount is applied per year—not per month. But since you’re billed monthly, your interest is calculated each month, using an average daily balance method.

Calculating your interest rate

Here’s how the average daily balance works:

  1. Determine the daily periodic rate (DPR)—the interest rate you pay each day. DPR is your current interest rate (it varies, remember) divided by 365. So, 18.25 / 365 = 0.05%.
  2. Determine the average daily balance for the month. This is done by adding up the balance for each day of the billing period, then dividing that sum by the number of days (either 30 or 31 days—or 28 in February!). If you had a balance of $0.00 for 10 days, then $500.00 for 10 days, then $1000.00 for the last 10 days of the month, your average daily balance would be $500.00.
  3. Multiply the DPR by the number of days in the billing cycle, then multiply that total by the average daily balance. This is your interest for the month. So, a DPR of 0.05% * 30 days = 1.5%. 1.5% * $500.00 = $7.50.

That might not sound like much, but if you’re an average cardholder in the United States, you’re carrying a credit card debt of $16,000.00. That means you’re paying $2,880.00 per year in interest alone, in this scenario.

How Can I Avoid Paying So Much Interest?

When you’re working hard to repair your credit card debt, it can be frustrating to be fighting against a high interest rate. But there are ways you can reduce—or even eliminate—the amount of credit card interest you’re paying each month.

Pay more than the minimum balance due

Your credit card statement lists a minimum amount that you must pay each month. Your interest for the month is rolled into that minimum payment. But if you pay more than the minimum, every dollar above that minimum goes towards your principal balance. There’s no interest charged on it.

In other words, if your minimum payment is $500.00 and you pay $600.00, that extra $100.00 is applied to the amount you borrowed—it’s interest-free. And that benefits you in two ways:

  • You’re paying off debt without paying interest
  • You’re lowering the dollar amount of interest you’ll have to pay next month, because your average daily balance will be smaller.

Open a balance-transfer credit card

credit card interest

A balance-transfer card can be a very helpful way to repair your credit card debt. A transfer credit card has a very low introductory interest rate—often as low as 0%. The card lets you transfer your balance from other debt onto the new card. You can then make monthly payments on the transfer card to pay down your existing debt.

But the low interest rate is only valid for a limited time—usually six to 18 months—so you’ll need to pay off the debt before the introductory rate expires. You should also do your homework: some transfer cards charge a transfer fee. And some charge a penalty APR, which allows the credit company to charge you a high interest rate if you miss a payment.

Pay off Your Credit Card Debt Faster

Your credit card’s annual interest rate doesn’t have to be a confusing mystery, and you don’t need to know everything there is to know about interest rates. But when you understand the basics of variable interest rates and how they’re calculated, you can use that information to repair your credit card debt faster and easier. Paying more than the minimum balance due and using a balance-transfer card can be very helpful ways to use interest rates to your advantage.


A reputable credit repair specialist can help you find other ways to successfully get out of credit debt. If you’re tired of struggling on your own, find out how our advisors can help you repair your credit debt. Contact us today.

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Source: lexingtonlaw.com

Managing Your Money, Together

To learn more about how our Minters are achieving their financial goals, we reached out to everyday Mint users, just like you, to hear their stories. Whether it’s paying off student loans, or working toward buying a home, we’re so inspired by the dedication this community has shown in working toward your goals and dreams.

One of the Minters we connected with is Jordan. He shared with us how he’s used Mint to reach a number of his financial goals. Check out his #EmpowerMint story:

My wife and I have been interested in getting out of debt ever since the day we took on student loans. With the desire to pay those loans off, we strived to learn more about budgeting and personal finance.

As we grew in our journey, there were many financial things we questioned that felt ‘normal.’ We heard so many messages that emphasized the need to have the newest toys to be happy, that having debt is normal, and that most people live paycheck to paycheck. We realized that we didn’t feel comfortable with any of that, and that we found satisfaction in being content with what we have. 

Knowing that money issues were often a problem area for couples, my wife and I started using Mint shortly after we got married in 2010 to ensure transparency and partnership from the beginning. We found Mint to be a terrific tool for us to have a complete picture of our financial situation. During this time, I was working full-time and my wife was finishing up her last year in nursing school. Mint was an immediate help in keeping track of where our money was going and in starting budget discussions that have proved to be invaluable in our marriage. It also helped initiate discussions on both near-term and long-term goals, which have been so key in helping us plan both strategically and aspirationally. 

As time went on, Mint was instrumental in helping us achieve so many of our goals including:

  • Paying off student loans
  • Paying for grad school with cash
  • Preparing for kids
  • Starting a 529
  • Saving for a down payment
  • Buying a home

Our current goal is to complete our 15-year mortgage in under 5 years. A combination of Mint, aggressive savings, overtime shifts, and side hustles have helped put us in a position to achieve this goal within the next 12 months. Once that goal is complete, we’re excited to have a little fun and celebrate this accomplishment, and then prepare for the next chapter in our financial journey. 

In addition to this goal, we also have various net worth milestones we would like to achieve in the next 1-, 5-, and 10-year periods. We are very excited about the concept of financial independence, and would like to be in a position where we have the opportunity to focus our attention on things outside of work, such as further investing in our family and causes that are important to us. With Mint, we can see how the choices we’re making are helping move us closer to achieving these goals. 

Today, we check Mint on a daily basis in order to stay on top of our expenses and monitor for any fraudulent activity. Years ago, Mint helped me identify a fraudulent charge almost immediately, enabling me to notify our bank and get the issue resolved. Reviewing our expenses enables us to stay within our budget, catch fraudulent activity, and follow the ‘every dollar’ budgeting rules that have been so helpful for us. In addition, linking our accounts has automated what would otherwise be a very manual and time-intensive process. 

I have also loved using the trends feature to have full visibility into exactly how our money is being spent and to help ensure we’re always partnering as we work towards our financial goals, rather than feeling like one person is pulling the other along. We can budget with transparency and not feel any need to hide transactions for personal expenses and rewards or small splurges. 

The trends feature has also allowed us to get a sense of what our typical spending has been in different categories. We periodically review our budget, and being able to easily see our historical spending in different categories has helped us set realistic targets, as well as track our progress when we are attempting to change habits. Lastly, being able to see changes in our net worth over the years has been inspiring, as we have been able to see in real-time how decisions to save or forego immediate gratification can have long-term benefits.

Beyond that, we have found a great deal of joy in doing things ourselves, whether it is cooking meals for the week, doing our own car maintenance, or trying to fix something ourselves before calling someone. Additionally, the satisfaction has compounded as we’ve seen that making these choices has helped us not only learn new things, but also in achieving our goals. 

Knowing what we know now, we’re really excited to pass these values on to our kids, and we’re happy to discuss them with anyone who asks. Additionally, I can see a ‘life’ after work that involves volunteering in some form in the personal finance field, whether that is teaching folks about budgeting or just encouraging them in their financial journey.

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Source: mint.intuit.com