There seems to be a bug at Shopify Checkout when using split shipping, carrier service rates and the rates have a mandatory phone number field. It was really hard to find the problem and I couldn’t find anything about this online so I thought I’d share it here, if anyone is looking for information about this.
I have reported this bug to Shopify with screen recording. It might have started early September 2025 - but that’s just a guess.
How to replicate the bug:
- Shopify Settings → Checkout → Select “Shipping address phone number” as required
- Use two or more shipping locations
- Add “phone_required” setting to the default shipping rate provided by third-party carrier service
- Create an order that includes items from multiple locations
- At Checkout, don’t change the shipping rates (use the selected defaults), and then try to continue to payment (you can replicate this with Bogus as well)
It will load a bit, and then the page just refreshes without any error messages.
If you open the shipping rates from the split shipping window, you can see that the shipping address phone number is populated correctly as it should be, but the bug still prevents the customer to continue to payment. If you change the shipping rate, or change it to another and then back to the original, it works normally.
It also works normally with orders that are shipped only from one location.