thread Invalid postcodes in Payments Troubleshooting

Invalid postcodes

chrisfarrow — Sun, 21 Sep 2025 13:25:53 GMT

Square payment processing on website with Storefront & woocommerce, latest versions of both. I'm getting repeated problems with uk postcodes not being accepted - customer is told their postcode is invalid. I've tested myself with the postcodes, they are definitely correct and definitely being input correctly. Any idea why the problem?

Re: Invalid postcodes

tonydow — Sun, 25 Oct 2020 14:30:38 GMT

It may be because they are using a space in the postcode or a space after it. Also don’t think it likes lower case letters. I have already suggested to Support that they force upper case on that field. Hopefully @Tra or @Helen can confirm exactly what is acceptable for entry.

Re: Invalid postcodes

tranguyen — Mon, 26 Oct 2020 15:23:08 GMT

Hi @chrisfarrow, really sorry to hear you are experiencing an issue with the Square payment integration! @tonydow is correct, the postal code should be in capital letters with no space between or after. Hopefully this will help!