Change Carrier Shipping Service Based Upon Weight

Shopify Partner
40 7 29

Hi, I'm trying to enable international shipping on my site. What I want to do is use the calculated shipping method for international orders with USPS. However, for orders that total 3 lbs and below I want to use First Class Package International and for orders that total greater than 3 pounds I want to use Priority Mail International.

This is fairly easy to set parameters for if I was creating my own shipping options, but I can't seem to find a way to do it while using carrier-calculated rates. Any ideas as to how to achieve this?

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Replies 2 (2)
126 6 16

Hey @wmiz,

Shopify only offers one package size to be sent off for live rate calculations, so you'll have to choose one package or the other for this scenario. If you're open to using a third-party app, Smart Boxing will solve this problem for you. You can enter as many package sizes as you want, and at checkout the app will choose the best package for the order. In the case where a customer orders enough items that they no longer fit just in the First Class Package box, it will send off two package sizes to the carrier. 

The only caveat is that you would have to enter your product dimensions, but this only has to be done once and also ensures accuracy for your live rates. Especially with international orders, mistakes can be costly. 


Warm regards,

Co-Founder / CEO @ Intuitive Shipping Inc.
Intuitive Shipping | Smart Boxing | Automate Shipping Profiles

Shopify Partner
797 31 100

Hi @wmiz,

Yes, as it is mentioned by Sharon, Shopify only offers one package size to be sent off for live rate calculations, which is chosen as the default package. The rates are calculated based on this default package. You can check out the Multi Carrier Shipping Label app that helps you handle this issue with ease. You can integrate your own carrier account and add custom boxes based on your product weight & dimensions. The app will then automatically choose the right package based on the input at checkout. If multiple items are ordered, the app will automatically choose the right box or add multiple boxes if required. 

Customer Success @ PluginHive
Shipping Automation | FedEx shipping | Multi-carrier shipping | Shipment Tracking | Australia Post shipping