Shopify App : Mighty PO Box Blocker

Warn customers against entering in PO Box addresses.

About Mighty PO Box Blocker

Block PO Boxes : Block PO Box addresses that FedEx, UPS and DHL do not deliver to.

Mobile Friendly : Optimized for both desktop and mobile devices.

Save time : Saves you time and money so you can focus on your business.


Say goodbye PO Box issues!

Do you primarily ship with FedEx, UPS or DHL?

If so, PO Box Blocker is an amazing solution for you! This app warns customers against using PO Box addresses, saving you time and money.

How does it work?

Whenever a PO Box address is detected, a warning is displayed on the cart view and/or the shipping method step of checkout. The warning informs customers that your store does not ship to PO Box addresses and instructs them to specify a valid residential or commercial address instead. You can fully customize the warning messages via the dashboard.


Because this app utilizes Shopify's carrier service feature for the warning during checkout, you must meet one of the following requirements to enable the feature:

  • Advanced Shopify plan or higher
  • Shopify plan is paid annually
  • Development store

If none of the requirements are met, you can contact Shopify Support to enable the carrier calculated shipping feature for $20/month - this fee is waived if you opt for annual billing.

After installation, enable the pop-up warning on cart by switching on the 'Shopping Cart' feature from app admin dashboard on your store.

Constant improvement

We are always adding new features and enhancements based feedback from merchants. Please reach out to us if you have any suggestions!

App Images
Launch date
May 07, 2020
App rating
Top features

Seamless workflow: use directly in Shopify admin

Speed tested: no impact to your online store

About the Author

Matej Kontros

Matej Kontros is an E-Commerce expert and app developer with over a decade of professional experience in IT.

Matej has worked for organisations of all types and sizes, including global players, startups, and agencies. He designed, developed, and maintained complex projects.

Matej's expertise includes e-commerce, software engineering, web development, systems administration, internet security, managing projects, and building teams.

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