It is not an obligatory procedure everywhere. Many points have canceled it as far as I know. But you always can check in Google. Area codes correspond to the official database which is free and accessible to everyone. So even if in some places you need to state zip code, just look for them online by the name of the location. It is simple and quick. But be sure to use the latest versions of codes.
Or just get a USA credit card! Many Canadian banks have US banks as well and will give you a US account. You can also add a US address to your Canadian card. Use the address for a USA CG.
If it does not work, you can go into the station and prepay.
I know that Costo, in the last 2 months no longer required me to enter the postal code.
Regards, Don My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.
As I understand it from our Canadian friends, the US zip code that is often required at gas pumps in the Us is 5 digits. The Canadian postal code is 3.
I just did a quick search, and the results said that if you needed 5 to just add two zeros to the end like two of our Canadian members posted above.
I have tried various methods, some work sometimes other times not. Seems to depend on the card carrier, area of the US and even the station brand. One that I tried and worked once only, was to use the 3 Numbers in your area code, followed by 00. Ours is L0G 1W0 so 01000. The only sure method involved going in to the cashier with the credit card or using your debit card at the pump.
Ken
2006 Winnebago Outlook 29B E-450. 2012 Honda CR-V AWD Blue Ox Aventa LX tow bar and Brake Buddy Vantage.