Hi everyone,
I’m running into a major issue with shipping calculations that is causing me to lose money on large orders, and I’m hoping someone can point me to the right fix or app.
The Scenario: I have two types of products with very different sizes.
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Product A (Large): 22" x 16" x 6" | 155 oz (approx 10 lbs)
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Product B (Small): 10" x 4" x 4" | 16 oz (1 lb)
The Problem:
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When a customer adds just the Large Item to the cart, the shipping correctly calculates to ~$20 (based on the specific package dimensions assigned to that product).
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However, if they add the Small Item to the cart as well (mixed cart), the shipping cost DROPS to ~$8.
My Theory: It seems like once there are multiple items in the cart, Shopify is ignoring the specific “Package” assigned to the product and reverting to my store’s Default Package (which is smaller). Because the total weight is still relatively low, the carrier (USPS) is quoting a price for a small box with heavy weight, rather than the large dimensional box required.
My Question: Is there a native Shopify setting to force the system to use the largest required box dimensions for the calculation? Or do I absolutely need a third-party app to handle “Smart Boxing” / Dimensional Packing?
If an app is required, which one do you recommend that doesn’t mess up my existing flat-rate rules for other products?
Thanks in advance!