How to read your credit card statement and know what you'll pay

A credit card statement is designed to disclose, not to be understood. You read it top to bottom and the biggest line is almost never the one that matters.

Here's every line it carries, what each one means, and the order to read them in.

The lines, one by one

Previous balance. What you owed at last month's close. If you paid in full, it's zero. If not, it's what was left — and interest runs on that.

Payments and credits. What you paid last month, plus any refunds credited back.

Purchases this period. Everything you bought between the last close and this one. Note: it's what was processed in that window, which doesn't always match the day you bought.

Instalments. This month's slice of purchases you made in instalments, sometimes months ago. Usually labelled with the instalment number: "3/12" is the third of twelve.

Interest and fees. Financing interest, insurance, administrative charges, annual fees. If you paid the full balance last month, there shouldn't be any financing interest.

Taxes. Whatever applies in your country to card spending, and particularly to foreign-currency spending.

Foreign-currency balance. If you bought abroad or from international services, it usually comes in a separate section with its own total.

Total due and minimum payment. The two big numbers at the bottom.

The only line that matters: the total due

The minimum payment is the most expensive trap in the whole document. It's printed next to the total, at the same size, as if they were two equivalent options. They aren't.

Paying the minimum means financing the rest at the card's rate, which is almost always the highest rate you will ever be offered in your life. It's the starting point of nearly every debt story that begins without anyone noticing.

Rule: if you can't pay the total, the problem isn't this statement any more. It's debt, and it gets treated as such — the method is in how to get out of debt.

How to spot a charge that shouldn't be there

Four passes, in this order, and they take five minutes:

1. Look for what you don't recognise. The name shown is the registered business name, not the shop's sign, so something can look unfamiliar and be legitimate. Search the name before disputing.
2. Look for duplicates. Same merchant, same amount, same day or the next one. It happens more than you'd think.
3. Check the subscriptions. This is the most profitable finding: cancelled once, saved permanently.
4. Count the instalments. If a purchase you made fourteen months ago in twelve instalments is still showing up, something is wrong.

If something doesn't add up, dispute it now. The windows for challenging a charge are short.

Why the number doesn't match what you logged

Three reasons, and none of them is an error:

• Processing date isn't purchase date. Something from the 30th can land on the following statement.
• Foreign purchases convert when processed, at that day's rate plus whatever surcharges and taxes apply. It always comes out higher than the conversion you did yourself. It's in spending money abroad.
• Instalments from old purchases show up even though the purchase was another month.

Which is why logging the instalment rather than the purchase is what makes your records and the statement resemble each other. It's in interest-free instalments.

In one line

Look at the total due and treat the minimum payment as what it is: the price of financing yourself at the most expensive rate you'll ever see. Then do the four passes — unrecognised, duplicates, subscriptions, instalments — and dispute on the spot.

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