Credit card numbers explained
Do you know what all of the numbers on your credit card mean? Let us tell you.

1. Credit card number
This is the 16-19 digit number on the front of your card. It’s completely unique to your card.

2. Start/expiry date
These numbers represent the month and year your card was issued, and when it will expire.

3. Security number
Also known as a ‘CVV’. For Mastercard and Visa, it’s the last three digits of the number printed in the signature strip.
Get to know these numbers in more detail
-
Sometimes called the ‘long number’, it features on the front of your credit card and can be anything from 16 to 19 digits in length. Its official name is a Permanent Account Number, or ‘PAN’.
Rather than being completely random, this number is unique to you, including information used to identify your account, card and who it’s issued by.
The first digit indicates the provider:
- Mastercard numbers start with two or five.
- Visa card numbers start with four.
- American Express numbers start with three.
The first six digits help to identify the issuer of the card, known as an Issue Identifier Number or ‘IIN’.
The numbers following that relate to your account, apart from the last one which is known as a ‘check digit’. This helps us to check that a full credit card number has been provided, in the right order, when you make a card payment or purchase.
This system for generating credit card numbers is used all over the world. It was invented in 1954 by IBM engineer Hans Peter Luhn.
-
These numbers indicate the month and year your card was issued, and when it expires. For example, 07/22 would be July 2022.
Credit cards are usually issued for two to four years, being renewed just before the expiry date. You might notice that the ‘expires end’ date is a month later than the ‘valid from’ date. This overlap gives you a bit of extra time to make the switch to your new credit card.
By the end of the ‘expires end’ month, your old card won’t work anymore, so it’s a good idea to start using a new card as soon as it arrives. That way, you’ll avoid any problems.
If your credit card is re-issued – for example, as a replacement for a lost card – your new card will have extended ‘valid from’ and ‘expires end’ dates.
For security, cards should be cut up and disposed of carefully when they expire.
-
When you buy something online or over the phone, you might be asked for a ‘CVV’, ‘CVC’, ‘CVN’, ‘CVV2’ or a ‘security number’. They’re actually the same thing.
This serves as a card verification number or code. Because it’s only printed on the card itself, when you provide it, we’re more confident that the physical card is in your possession.
On Mastercard and Visa credit cards, you’ll find the security number on the back of your card. It’s the last three digits of the number printed in the top right-hand corner of the signature strip.
On American Express credit cards it’s a 4-digit number printed on the front, just above and to the right of the long credit card number.
Card PINs
Your Personal Identification Number or ‘PIN’ is one number you won’t find printed or embossed on your card. It’s the four-digit number you enter to make payments in-store, or at an ATM to withdraw cash.
- Waiting for a new card?
When you’re issued a new card and PIN, for security they’ll be delivered separately. Your PIN is highly sensitive information, so only you should know what it is.
- Locked your card?
If you’ve locked your card by using the wrong PIN, you can unlock it at a LINK cashpoint, but you’ll need to know the correct PIN to do this.
- Need to change your PIN?
You can change your PIN at any UK cashpoint which displays the LINK logo. It’s important to pick something that’s easy for you to remember, but not easy for someone else to guess.
- Think someone knows your PIN?
You should change it straight away. If you’re ever worried that your account is at risk, you should contact us straight away.
Key points about credit card numbers
There are lots of numbers on your credit card, and they all have special jobs.
- The long credit card number is 16-19 digits long and is unique to you.
- ‘Valid from’ and ‘expires end’ indicate the month and year your card is issued and expires.
- For Mastercard and Visa, the ‘CVV’ or ‘security number’ is included on the signature strip.
- To use your card in-store or at an ATM, you’ll need your PIN.
Want to read more?
Halifax is a division of Bank of Scotland plc. Registered in Scotland No. SC327000. Registered Office: The Mound, Edinburgh EH1 1YZ. Bank of Scotland plc is authorised by the Prudential Regulation Authority and regulated by the Financial Conduct Authority and the Prudential Regulation Authority under registration number 169628.