Routing Orders: How Spark Shipping makes the decision to route orders

When an order is received, Spark Shipping automatically routes it to a vendor based on your Product SKU Mapping. However, if a product is mapped to multiple vendors, the system needs a logic "tie-breaker" to decide which source is best.

You can configure these rules in Spark Shipping under Sites > Your Site > Order Routing. Below is a breakdown of every available routing method.

1. Lowest Cost

This is the default logic (new sites start with it) for maximizing profit margins through a three-step waterfall process:

Primary: Route to the vendor with enough stock and the lowest total cost.
Fallback 1: If no vendor has both cost data and enough stock, route to the vendor with the most stock.
Fallback 2: If no vendor has stock, route to the vendor with the lowest total cost; if there is no cost data either, route to the first vendor on your mapping list.

Total cost is the vendor's cost plus any markup, shipping cost and handling fee set for that vendor.

2. Lowest Cost With Backorders

This logic prioritizes price even when stock is unavailable:

Primary: Route to the vendor with stock and the lowest total cost.
Backorder Logic: If all vendors are out of stock, route to the vendor who accepts backorders with the lowest total cost.
Fallback: If no cost/stock data exists, it defaults to the most stock, then the first vendor on the mapping list.

3. Lowest Warehouse Distance

This method prioritizes shipping speed and reducing "Last Mile" costs.

Requirement: You must set up Vendor Warehouse Addresses for this to function.
Route by Country First: When enabled, the system always selects warehouses within the same country as the customer.
Split Order Items (Beta): A single order line item can be split between multiple vendors if one vendor doesn't have enough stock to fulfill the total quantity.

4. Vendor Priority

This allows for manual control over your supplier relationships.

Ranking: You set a preferred priority list of vendors. You can select just one vendor or create a list of priority.
Stock Check: With Check stock, you can toggle whether the system should verify stock before sending the order to your top priority.
Consolidation: With Send as few shipments as possible, Spark Shipping prioritizes sending as few shipments as possible. When enabled, grouping items into one shipment takes precedence over your manual priority ranking to save on shipping fees.

5. Location-Based Routing (Country or State/Province)

These methods allow for strict geographic fulfillment boundaries:

Country: Routes orders to specific vendors based on the destination country.
State/Province: Routes orders to specific vendors based on the destination state or province.
Example: All orders shipping to California are sent to your West Coast 3PL, while all others go to your central warehouse.
Default Order Routing Vendor: Orders that don't match any of your country or state/province rules go to this vendor.

6. Shipping Method

This logic relies on the customer's choice at checkout.

How it works: Orders are routed based on the Shipping Method Code (e.g., "Standard," "Overnight," or "Ground") imported from your storefront.
Orders whose shipping method doesn't match any rule go to the Default Order Routing Vendor.

Logic Summary Comparison

Logic Method	Prioritizes	Best For...
Lowest Cost	Profit	High-competition items with many suppliers.
Warehouse Distance	Speed	Minimizing transit times and carbon footprint.
Vendor Priority	Control	Using a preferred "Primary" supplier first.
Country/State	Logistics	Multi-warehouse or international operations.

Pro-Tip: Data Accuracy

Most of these routing methods—especially Lowest Cost and Lowest Distance—rely on accurate Vendor data. Ensure your vendor connections and warehouse addresses are fully updated to prevent routing errors.

You can always override the routing for a single line item from the order page with Override Vendor. See Processing orders, partial orders and overriding pre-selected vendors.