When customers edit their order, the cart can change in ways that should affect shipping cost — added items, a different address, different weight, different zone. The Shipping Cost Recalculation section controls whether the shipping line is automatically recalculated when that happens, and which shipping methods it applies to.
What "recalculation" means
With recalculation turned on, the app looks at the edited order and asks your Shopify shipping rules what the shipping should cost now. If it's different from what the customer originally paid, the shipping line is updated automatically.
Recalculation is triggered by any of these changes during an edit:
Quantity change — more or fewer of a line item
Add a product — new items in the cart
Replace a product — swap to a different product
Change variant — swap to a different variant of the same product (can change weight or price)
Change shipping address — different postal code, state, or country means different shipping rates
With recalculation off, the shipping line stays at whatever the customer paid at checkout, no matter how much the cart or address changes.
Turning it on
Toggle Recalculate shipping costs after edits on.
Save.
That's it for the basic setup. Shipping will now be re-checked on every edit that could affect it.
Eligible shipping methods
Once recalculation is on, a second control appears: Eligible shipping methods. This lets you limit recalculation to specific shipping tiers.
There are two modes:
Empty (default): All shipping methods are recalculated. The settings page shows an info note reminding you of this: "No specific methods selected — shipping costs will be recalculated for all shipping methods."
Populated: Only orders whose current shipping method matches one of the selected methods are recalculated. Orders using any other method keep their original shipping price.
What's next
Choosing the Refund Method for Downgrades — what happens when recalculation ends up owing the customer money
Choosing Which Changes Customers Can Make — the edit actions that actually trigger recalculation