A credit card postal code is simply the primary cardholder’s postal code, part of their mailing address. Some merchants may ask you to enter your postal code to help verify your identity before processing a credit card transaction.
However, if you’re a frequent traveller between Canada and the U.S., you might occasionally be asked for your credit card ZIP code.
Understanding the details — and the difference between credit card ZIP codes and postal codes — is important for proper credit card use no matter where you are.
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What is a credit card postal code?
Postal codes in Canada are a six-character string consisting of three letters and three digits. For example, M4B 1G5. Every mailing address has a postal code, which helps Canada Post sort mail.
If you’re ever prompted for your credit card postal code when making a purchase online or over the phone, use the postal code from the billing address that’s on file with the card company.
What is a credit card ZIP code?
Residents of the United States have ZIP codes instead of postal codes. ZIP codes are five-digit numbers, such as 90210.
If a U.S. cardholder is asked to enter their credit card ZIP code when making a purchase, they would enter the ZIP code from the billing address that’s on file with the card company.
Why credit card postal codes and ZIP codes matter
Your postal code or ZIP code acts as a security measure. When making purchases online with a credit card, you’ll usually be prompted to provide the mailing address associated with your card. This serves as a security check to ensure that you’re the one using your card. Some sites may ask you for just your postal code.
While this system is not foolproof, it can help prevent thieves from charging fraudulent transactions to your card if all they have is your name and credit card number.
Tips for using a Canadian postal code at U.S. gas pumps
If you plan on paying at the pump, most U.S. gas stations will require you to enter your ZIP code to authorize the transaction. This requirement presents a problem if you’re paying with a Canadian credit card, since you can’t enter a postal code using letters and numbers.
Fortunately, there’s an easy solution. When prompted for your ZIP code, enter the three digits from your postal code, followed by “00.”
For example, if your postal code is M4B 1G5, your credit card ZIP code would be 41500. This strategy is recommended by Mastercard. Many people also report that it works for Visa and American Express cards, though these companies haven’t provided any official recommendations.
What happens if my ZIP code or postal code doesn’t work?
If you try the “00” ZIP code strategy and the credit card is declined, you can also go inside the station and pay at the counter with your card or cash before fueling up.
Some credit card providers may require you to call them in advance if you plan on using your card while travelling. If you forget to do so, it’s possible your card will be blocked when you attempt to make a purchase outside of Canada.
When making an online purchase, make sure you’ve selected the right country of residence for your billing and/or shipping address. If you select the United States, you’ll be prompted to enter your ZIP code. If you enter a Canadian address, you’ll see a place to enter your postal code.
Another reason the transaction might not go through is that the name and address you entered don’t match what’s on file with your credit card issuer. Double-check that you’ve entered the correct information, including spelling and spacing. Don’t forget to check your credit card number, expiry date, and security code to ensure they’re accurate, too.