Walmart Enhances Shipping Settings API to Support Multiple Carriers
Walmart enhanced the Simplified Shipping Settings API, allowing sellers to configure multiple carriers at each shipping-speed tier and compare and select carriers after order creation.
What are the key facts?
- 1Walmart Developer Platform released an enhanced API version
- 2Multiple carrier services can be configured within the same shipping-speed tier
- 3Carriers can be compared and selected after order creation
- 4Sellers need to upgrade API integrations and test logistics data flows
What happened?
The Walmart Developer Platform released an enhanced version of the Simplified Shipping Settings API on October 15, 2026. The new version allows sellers to configure one or more carrier services within shipping-speed tiers such as Value, Standard, Expedited, and Rush, and compare and select carriers after an order is created. This changes the previous approach, which relied on only one recommended carrier.
For cross-border sellers using ERP systems, WMS platforms, third-party warehouses, or automated fulfillment systems, the update enables dynamic selection among USPS, UPS, FedEx, and other services based on destination, package weight, regional surcharges, and real-time carrier prices. The feature may help reduce shipping costs for remote areas and reduce performance issues caused by discrepancies between promised and actual delivery times.
The main affected groups include sellers using merchant-fulfilled shipping outside Walmart Fulfillment Services, multi-warehouse sellers, U.S.-based 3PL sellers, and medium to large merchants that automatically assign logistics channels through software. These sellers need to upgrade their API integrations and retest carrier mapping and tracking-number return logic.
What does this mean for cross-border sellers?
Walmart now allows sellers to configure multiple carriers within the same shipping-speed tier and compare and select them after order creation. Sellers using merchant-fulfilled shipping, ERP, WMS, multiple warehouses, or third-party warehouses can manage logistics costs more flexibly. If carrier mapping or tracking-number returns fail after the upgrade, fulfillment data and promised delivery performance may be affected, so complete interface and order-flow testing first.
What should sellers do now?
- 1Upgrade the Simplified Shipping Settings API for merchant-fulfilled stores this week, configuring carrier mappings one by one for the Value, Standard, Expedited, and Rush tiers; verify tracking-number returns with test orders and retain passing records.Dimensional weight
- 2For multi-warehouse or U.S.-based 3PL stores, create a carrier-selection table based on destination, package weight, regional surcharges, and real-time prices, covering USPS, UPS, and FedEx; save screenshots or exported tables of the configurations for each shipping tier.
- 3Sample merchant-fulfilled orders and record the candidate carriers, selected carrier, shipping cost, and tracking number after order creation; prioritize remote areas and promised delivery times, produce an exception list, and complete corrections.Profit calculator