Maybe someone knows how to exclude fast shipping options for addresses with PO Boxes? We offer only standard shipping when buyer orders to P.O. Boxes and we couldn't find any way to not show Expedited and Priority shipping options for buyer with these addresses.
If you're open to using a third-party solution, Intuitive Shipping has a simple PO Box condition that you can add to shipping Scenarios to either allow or prevent checkouts from customers with a PO box address, depending on the carrier. So, you can have one Scenario that allows PO Box addresses and has standard shipping options, then have another Scenario that prevents PO boxes and has expedited shipping options.
Please feel free to schedule a demo with one of our team members who will be happy to walk you how this setup can work and answer any questions you might have.
Intuitive Shipping is free to install and use in Setup & Testing mode, so you can make sure it's a good fit for your store before activating any billing.
Please note that to use Intuitive Shipping - or any third-party rate calculation app - Shopify requires that you enable their third-party carrier-calculated shipping rates feature. This feature is $20 USD per month. If you change your Shopify billing to annual, they will add the feature at no additional cost (plus they will reduce your billing plan by 10%). If you're on the Advanced plan or higher, this feature is already included and activated by default.