American Express interest calculator

How to use our Amex interest calculator

First select the specific Amex that you have, and the calculator will fill in the fields it can automatically. Don’t worry – you can override these if you want. If you’re not absolutely sure what Amex you have, it’s at the top of the first screen of the app when you open it.

One of the fields that can be automatically filled in for you is the interest rate charged on purchases (note this isn’t the APR, because the APR factors in the account fee, if there is one). We use the interest rate that most cardholders are charged, but card issuers sometimes tailor rates to individuals (if you have worse credit, you might be charged a higher rate). To check what rate you actually pay, you need to look at your most recent statement, which you can do in the app via “Statements and Activity”. You’ll need to download it and open the PDF (card issuers don’t seem to like making it easy to find out your personal rate after opening an account!).

Some limitations of the calculator

As well as not knowing your personal interest rate, at the moment the calculator doesn’t consider any account fees – just the interest. If you only make the minimum monthly repayments, these may include a twelfth of the annual fee. You can also incur fees for improper use or non-sterling transactions.

The calculator is designed to work out the cost of clearing existing debt, so it also assumes you don’t use the card for additional spending.

Ultimately the calculator’s intended as a guide and shouldn’t be taken as gospel, but we think it’s a useful way to gauge overall costs and what you might save through a balance transfer (that’s where you shift your debt across to a new card issuer, which rewards you with 0% interest for a set period).

What if I don’t carry a balance from month to month?

If you pay off your balance in full every month, then your Amex might not cost you a penny, thanks to your interest-free days! But there are a couple of exceptions to that rule. Using your card overseas, for example will incur a fee. Cash advances (withdrawing cash or getting cashback at the till) will too – and doing that is a bad idea anyway because it can damage your credit score.

Written by

Chris Lilly

Head of publishing

Chris Lilly is Head of publishing at finder.com. He's a specialist in personal finance, from day-to-day banking to investing to borrowing, and is passionate about helping UK consumers make informed decisions about their money. In his spare time Chris likes forcing his kids to exercise more. See full bio

Chris's expertise

Chris has written 602 Finder guides across topics including:

• Loans & credit cards
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