EDI 940 and 945 Explained: How Warehouse Shipping Orders and Confirmations Work

If you’re looking to understand how EDI 940 and 945 work together in warehouse operations, this article will provide clarity.

1. Why EDI 940 and 945 Matter in Warehouse Fulfillment

EDI 940 and 945 connect two critical moments in warehouse fulfillment: what a business asks a warehouse to ship and what the warehouse actually ships. Therefore, the documents help an ERP, warehouse management system, and 3PL stay aligned as orders move through fulfillment.

However, the value goes beyond simply sending two electronic files. Instead, the workflow can affect inventory availability, shipment status, tracking, customer communication, invoicing, and downstream EDI transactions.

As a result, a weak 940/945 process can create problems even when the warehouse itself works efficiently. For example, a shipment may physically leave the dock while the ERP still shows the order as open.

1.1 The request-and-response loop

First, the business creates or approves an order in its ERP or order management system. Next, the system sends warehouse instructions through an EDI 940.

Then, the warehouse or 3PL receives the request and performs the operational work. For example, the team may allocate stock, pick units, pack cartons, generate labels, and release the shipment.

Afterward, the warehouse sends the shipment result back through an EDI 945. Consequently, the originating system can compare requested quantities with actual shipped quantities.

Therefore, the simplest way to remember the workflow is:

940 = what should ship

945 = what actually shipped

Although that sounds simple, the distinction becomes extremely important when shortages, partial shipments, multiple cartons, substitutions, or tracking updates enter the process.

2. EDI 940 and 945: The Core Difference

Although EDI 940 and 945 work as a pair, they serve different business purposes. Specifically, the 940 communicates instructions before warehouse execution, while the 945 communicates results after shipment activity.

Therefore, the documents should not be treated as interchangeable. Instead, one starts warehouse fulfillment, while the other helps close the operational loop.

Attribute	EDI 940	EDI 945
Formal purpose	Warehouse Shipping Order	Warehouse Shipping Advice
Main question	What should ship?	What actually shipped?
Typical sender	ERP or inventory owner	Warehouse or 3PL
Typical recipient	Warehouse or 3PL	ERP or inventory owner
Timing	Before fulfillment	After shipment
Quantity	Requested quantity	Actual shipped quantity
Main effect	Starts warehouse execution	Confirms and reconciles execution
Tracking	Usually not final tracking	May include shipment details

2.1 Warehouse Shipping Order vs Warehouse Shipping Advice

An EDI 940 is generally created when an order becomes ready for warehouse execution. Therefore, it may include the order reference, destination, item identifiers, quantities, requested dates, and shipping instructions.

Meanwhile, the 945 reports the warehouse outcome. Consequently, it can return actual shipped items, quantities, dates, carrier details, tracking information, and other shipment data depending on the implementation.

For example, an ERP may request 80 units through the 940. However, if only 76 units are available, the warehouse may ship 76 and report that quantity in the 945.

Therefore, the ERP should not automatically assume that the requested quantity and shipped quantity are identical.

3. How EDI 940 and 945 Move Through the Fulfillment Cycle

To understand EDI 940 and 945, it helps to follow a typical order from creation to shipment confirmation.

First, an order enters the ERP from ecommerce, wholesale, EDI, a sales representative, or another channel. Next, the ERP determines which warehouse should fulfill the order.

Then, inventory may be allocated to prevent the same stock from being promised elsewhere. After the order reaches the correct release status, the system can create the 940.

The warehouse then receives the message and creates the corresponding warehouse work. Finally, once the shipment is completed, the 945 returns the actual execution information.

3.1 From ERP release to shipment confirmation

A practical workflow may look like this:

1. Customer or retailer order enters the ERP.
2. Inventory becomes allocated.
3. ERP releases the order.
4. EDI 940 moves to the warehouse or 3PL.
5. Warehouse validates the request.
6. Warehouse picks the items.
7. Warehouse packs the shipment.
8. Carrier and tracking details are created.
9. Shipment leaves the warehouse.
10. EDI 945 returns to the ERP.
11. ERP records actual fulfillment.
12. Inventory and downstream processes update.

Therefore, the workflow is not simply:

940 → 945

Instead, the real sequence is:

Order → ERP → 940 → Warehouse → Pick → Pack → Ship → 945 → ERP → Inventory and downstream updates

As a result, every handoff matters.

4. What Data Moves Through the 940/945 Workflow?

The documents may contain different fields depending on the X12 version, warehouse, EDI provider, and trading-partner implementation. Nevertheless, the operational categories remain similar.

For example, a warehouse must know which order it is processing, which items are involved, how many units were requested, and where the goods should go.

Likewise, the business receiving the warehouse response must know which order actually shipped and whether the warehouse completed the original request.

Therefore, reliable identifiers are essential.

4.1 Order data on the way out, shipment data on the way back

Typical information associated with the outbound warehouse order can include:

• Order number
• Customer reference
• Ship-to information
• Warehouse location
• SKU or item identifier
• Requested quantity
• Requested ship date
• Shipping instructions
• Carrier or service requirements
• Special handling details

Meanwhile, the returning warehouse advice may include:

• Original order reference
• Actual shipped items
• Actual shipped quantities
• Shipment date
• Shipment number
• Carrier information
• Tracking information
• Carton details
• Lot or serial data where applicable

Therefore, the workflow needs strong mapping between the two sides.

Outbound information	Operational purpose	Returned result
Order number	Identify fulfillment request	Original order reference
SKU	Identify product	Shipped item
Requested quantity	Define pick demand	Actual shipped quantity
Ship-to address	Route shipment	Shipment destination
Service request	Define shipping method	Actual carrier/service
Warehouse	Assign location	Fulfillment source

5. EDI 940 and 945 vs Other X12 Transactions

EDI 940 and 945 do not operate in isolation. Instead, they often sit inside a wider chain of transactions connecting buyers, suppliers, warehouses, and financial systems.

For example, a retailer may first send a purchase order to a supplier. Afterward, the supplier may communicate with its warehouse or 3PL before sending shipment information back to that retailer.

Therefore, understanding adjacent transactions helps prevent one common mistake: assuming that every shipping-related EDI document performs the same job.

They do not.

5.1 Where 850, 855, 856, 810, and 997 fit

A simplified relationship looks like this:

Transaction	Primary business role
850	Purchase Order
855	Purchase Order Acknowledgment
940	Warehouse Shipping Order
945	Warehouse Shipping Advice
856	Advance Ship Notice / Ship Notice
810	Invoice
997	Functional Acknowledgment

For example, the buyer may send an 850 to the supplier. Next, the supplier may send a 940 to its 3PL.

After the warehouse ships, the supplier may receive a 945. Consequently, that shipment data can support an outbound 856 to the buyer.

Likewise, the shipment event may support invoicing through an 810.

However, a 997 is different. It confirms EDI processing at a technical level; therefore, receiving a 997 does not prove that warehouse fulfillment occurred.

6. Common EDI 940 and 945 Failure Points

Even when EDI 940 and 945 messages transmit successfully, the business process can still fail. Therefore, operations teams need visibility into what happens after each file reaches the next system.

For example, a warehouse may successfully receive a 940 but fail to create the corresponding order because a SKU does not match.

Likewise, a valid 945 may return but fail inside the ERP because its order reference cannot be identified.

Consequently, monitoring only file transmission is not enough.

6.1 Why successful EDI delivery can still fail operationally

Common failure points include:

• Missing order references
• Incorrect SKUs
• Unit-of-measure mismatches
• Wrong warehouse identifiers
• Short shipments
• Unexpected over-shipments
• Missing 945 messages
• Duplicate 945 messages
• Missing tracking data
• Late shipment updates
• Failed ERP posting
• Incorrect location mapping

For example, imagine that a 940 requests 50 units while the warehouse ships only 47. Therefore, the ERP needs a defined rule for the remaining three units.

It might keep them open, place them on backorder, cancel the balance, or raise an exception.

Similarly, duplicate messages require controls. Otherwise, a repeated 945 could accidentally create duplicate fulfillment activity.

As a result, strong warehouse EDI depends on exception handling as much as message mapping.

7. Building a Reliable ERP, WMS, and 3PL Architecture

A reliable warehouse EDI process begins with system ownership. Therefore, the business must decide where orders, inventory, fulfillment, and financial results officially live.

For example, the ERP may own the sales order while an external WMS owns warehouse execution. In that case, both systems must agree on identifiers, quantities, timing, and status.

Alternatively, businesses may operate through a more unified environment. For example, XoroONE connects ERP functions such as inventory, warehouse operations, accounting, purchasing, ecommerce, and operational reporting.

However, integration architecture still matters even when more functions live together.

7.1 Make one system responsible for operational truth

First, the company should decide which system represents the authoritative order. Next, it should define which system owns inventory availability and shipment status.

For warehouse execution, a connected warehouse management system can coordinate receiving, inventory, picking, packing, and shipping activity.

Meanwhile, external 3PLs may still perform physical fulfillment. Therefore, the integration needs to return their results into the operational system of record.

A strong design should clearly answer:

• Where does the sales order live?
• Where is inventory reserved?
• Which system releases fulfillment?
• Which system records shipment?
• Where is tracking stored?
• How are discrepancies handled?
• When does accounting update?
• Who owns an integration exception?

Therefore, automation should not simply move data faster. Instead, it should preserve one consistent operational truth.

8. Where Warehouse EDI Delivers the Most Value

Warehouse EDI becomes especially useful when order volume, partner count, or fulfillment complexity increases.

For example, wholesale distributors may serve many customers while storing inventory across several warehouses. Therefore, manual warehouse instructions quickly become difficult to control.

Similarly, apparel, sporting goods, consumer products, food, furniture, and manufacturing businesses can face large SKU counts, seasonal demand, multi-location inventory, and external fulfillment requirements.

Companies can also review Xorosoft’s broader industries served when evaluating how ERP and warehouse processes differ by operating model.

8.1 Common wholesale, multi-warehouse, and ecommerce scenarios

In wholesale distribution, warehouse instructions may originate from retailer orders, sales orders, or EDI demand. Consequently, accurate shipment feedback is critical for inventory and customer service.

Meanwhile, ecommerce creates another layer. For example, a Shopify order may enter the ERP, route to a 3PL, and later require shipment and inventory updates back across connected systems.

For teams evaluating that type of ecosystem, the Xorosoft ERP listing on the Shopify App Store provides an example of an ecommerce ERP connection.

Likewise, multi-warehouse businesses need strong location mapping. Otherwise, the correct order can reach the wrong fulfillment node.

Therefore, the value of EDI grows as the number of channels, warehouses, customers, and partners increases.

9. EDI 940 and 945 Implementation Checklist

Before implementing EDI 940 and 945, businesses should define the operational rules first and map fields second.

Otherwise, the team may build a technically valid integration that still behaves incorrectly during real warehouse exceptions.

For example, the integration team must know what should happen when the warehouse ships fewer units than requested. Likewise, it needs a rule for duplicate messages and unmatched items.

Therefore, the implementation plan should cover normal transactions and failure scenarios.

9.1 Test business outcomes, not only message delivery

Before go-live, validate the following:

• Confirm the X12 version.
• Confirm partner implementation requirements.
• Define the event that creates the 940.
• Map warehouse identifiers.
• Map SKU and partner item identifiers.
• Confirm units of measure.
• Define partial-shipment rules.
• Define cancellation behavior.
• Define order-change behavior.
• Confirm carrier requirements.
• Confirm tracking requirements.
• Test multi-carton shipments.
• Test lot or serial data where required.
• Test unmatched orders.
• Test invalid SKUs.
• Test short shipments.
• Test duplicate 945 messages.
• Test missing 945 messages.
• Confirm inventory updates.
• Confirm fulfillment posting.
• Confirm ASN dependencies.
• Confirm invoice dependencies.
• Assign exception ownership.

Therefore, a test should not end when the receiving system accepts the message.

Instead, it should confirm that inventory, fulfillment, tracking, customer status, and accounting reach the correct final state.

10. Choosing a Scalable Warehouse EDI Setup

As businesses grow, warehouse EDI architecture usually becomes more important than the individual document format.

For example, a small operation may begin with an ERP, a warehouse application, spreadsheets, and a standalone EDI service. However, every additional system creates another point where identifiers and timing can diverge.

Therefore, businesses should evaluate whether the surrounding architecture supports the volume and complexity they expect over the next several years.

An integrated platform does not eliminate EDI rules. Nevertheless, it can reduce unnecessary handoffs.

10.1 What to evaluate before upgrading

A growing inventory-driven business should evaluate:

• Multi-warehouse inventory
• EDI connectivity
• 3PL integration
• Purchasing
• WMS functionality
• Order management
• Ecommerce connectivity
• Accounting integration
• Exception reporting
• Inventory forecasting
• Shipment tracking
• Operational reporting

For example, Xorosoft integrations connect ecommerce, EDI, marketplaces, warehouses, shipping, and other operational systems.

Likewise, companies that need broader ERP functionality can evaluate XoroERP when moving beyond accounting software, spreadsheets, or disconnected inventory tools.

However, software selection should still start with operational requirements.

Therefore, the right question is not simply, “Can the system send a 940?”

Instead, ask, “Can the complete business accurately process the order from release through warehouse execution, inventory reconciliation, fulfillment, and accounting?”

11. Turn Warehouse Messages into Operational Truth

EDI 940 and 945 are valuable because they connect warehouse instructions with warehouse results. Therefore, they help inventory-driven companies move from an intended shipment to a recorded shipment without depending on manual updates.

However, EDI alone does not guarantee operational accuracy. Instead, the surrounding ERP, WMS, 3PL, inventory, and accounting processes must interpret every event correctly.

As a result, the strongest setup creates clear ownership from the moment an order is released until the shipment is reconciled.

For growing ecommerce, wholesale, distribution, and manufacturing businesses, that often means reducing spreadsheet handoffs and disconnected applications.

Therefore, if your warehouse confirmations, inventory updates, and fulfillment records regularly fall out of sync, evaluate the complete workflow rather than fixing each file manually.

To see how Xorosoft connects ERP, WMS, inventory, orders, EDI, and fulfillment, Book a Demo.