The EDI 945, Decoded: A Warehouse Shipping Advice Is Proof, Not Paperwork

The EDI 945 · Warehouse Shipping Advice is the document a warehouse or 3PL sends back to the seller after it ships an order, reporting what actually left the dock — which items, in what quantities, under which carrier and tracking details. It answers the 940 · Warehouse Shipping Order. The 940 is the instruction; the 945 is the evidence that the instruction was, or was not, carried out exactly as sent.

If you outsource fulfillment, the 945 is the first truthful record of a shipment. Everything downstream — the 856 · Ship Notice / ASN to the buyer, the 810 · Invoice, the inventory balance — should be built from it, not copied forward from the original order.

What is the EDI 945 · Warehouse Shipping Advice?

The 945 is an X12 transaction set sent by a warehouse, distribution center, or 3PL to the depositor — the seller whose goods it stores and ships. It closes the loop opened by the 940.

Think of the chain it completes:

• The 850 · Purchase Order says what the buyer ordered from the seller.
• The 940 · Warehouse Shipping Order says what the seller told the warehouse to ship.
• The 945 · Warehouse Shipping Advice says what the warehouse shipped.
• The 856 · Ship Notice / ASN tells the buyer what is coming, based on that shipped reality.
• The 810 · Invoice bills for what shipped, not for what was merely ordered.

When the 945 matches the 940 line for line, the rest of the flow is routine. When it does not — a short pick, a substitution, a split shipment, a different carrier — that difference is not a warehouse footnote. It is a change to what the buyer should be told and what they should be billed.

What does a 945 actually contain?

At the header, the 945 identifies the shipment being reported: the warehouse, the depositor, the shipment and order references that tie it back to a specific 940, the ship date, and the carrier and service level actually used.

At the line level, each item reports the quantity shipped — and, in implementations that use it well, the quantity ordered alongside it, so a shortfall is visible in the document itself rather than discovered by subtraction later. Product identifiers should match the identifiers on the 940, in the same unit of measure. A 945 that reports cases where the 940 ordered eaches has not confirmed anything; it has created a second translation problem.

Many implementations also carry carton, weight, and tracking or bill-of-lading references. Those details matter because they are the link between the digital record and a physical box a carrier can find. An ASN built without them is a promise; an ASN built from them is a report.

Why is the 945 different from the 856 · Ship Notice / ASN?

This is the confusion that breaks otherwise good flows. The 945 and the 856 can look similar — both describe a shipment — but they have different senders, different recipients, and different jobs.

The 945 goes from the warehouse to the seller. It is an internal confirmation inside the fulfillment relationship: we shipped this, for you, like this.

The 856 goes from the seller to the buyer. It is an external commitment to a trading partner, often under a compliance program with deadlines and chargebacks: this is what is coming to you.

The seller's job in the middle is reconciliation. Read the 945, compare it to the 940 and the underlying 850, resolve any difference, and only then build the 856 from the reconciled result. Skipping that middle step — generating the ASN straight from the order — is how buyers get told a full order shipped when the warehouse had already reported, clearly, in the 945, that it did not.

Where do 945 flows usually break?

The first break is the unexamined confirmation. The 945 arrives, gets filed, and nobody compares it to the 940. A line shipped short, or not at all, travels onward into the ASN and the invoice as if it had shipped in full. The buyer discovers the truth at receiving — the worst possible place, with a claim, a chargeback, and a receiving team holding physical evidence that contradicts your paperwork.

The second break is the partial shipment treated as complete. Warehouses split shipments for ordinary reasons: stock in two locations, a back-ordered line, a carrier cutoff. A good 945 flow reports each partial shipment as its own advice, clearly linked, so the seller can decide whether the buyer gets one ASN per shipment or a consolidated view. A weak flow overwrites the first advice with the second, and the record of what shipped first quietly disappears.

The third break is timing. A 945 that arrives days after the truck leaves has lost most of its value. The ASN deadline is already running, the buyer may already be asking where the shipment is, and the window to correct a carrier or quantity mistake before it becomes a compliance failure has closed. The advice has to be prompt to be useful — same-day, tied to the ship event, not batched as an end-of-week summary.

What should you check when a 945 arrives?

Three comparisons, in order, catch most of the damage:

First, quantities: shipped versus instructed on the 940, line by line, in the same unit of measure. Any difference needs a named reason — short stock, damage, a cancelled line — not just a smaller number.

Second, identity: carrier, service level, and tracking references versus what the order required. A shipment that went out on the wrong service level can be a compliance failure even when every item is correct.

Third, completeness: does this 945 close the 940, or is more still to ship? An open remainder should stay visibly open — as a back order, a second shipment, or a cancellation the buyer agrees to — rather than fading into an assumption that it will sort itself out.

A flow that runs those three checks automatically, and holds the ASN until they pass or a person resolves them, turns the 945 from paperwork into control.

Frequently asked questions

Is the 945 · Warehouse Shipping Advice the same as the 856 · Ship Notice / ASN?
No. The 945 is the warehouse reporting to the seller what it shipped. The 856 is the seller telling the buyer what is coming. The 945 is the source; the 856 should be built from it after reconciliation.

Who sends the 945 and who receives it?
The warehouse, distribution center, or 3PL sends it; the seller or brand owner whose goods were shipped receives it.

What document does a 945 answer?
The 940 · Warehouse Shipping Order. The 940 instructs; the 945 confirms what was actually done about that instruction.

What happens if a 945 reports less than the 940 ordered the warehouse to ship?
That is a short shipment. The seller should not build a full-quantity ASN or a full-quantity invoice from the original order. Reconcile first: notify the buyer accurately, decide whether the remainder ships separately or is cancelled, and bill only for what shipped.

Does every business need a 945?
Only businesses that use a separate warehouse or 3PL need this specific loop. If you ship from your own dock, your own shipping system is the source of truth — but you still need the same discipline: build the ASN and invoice from what actually shipped, not from what was ordered.

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An instruction without a confirmation is just a hope with a control number. At SignalEDI, we treat the 940/945 loop as a first-class part of the order flow — the 945 is reconciled against the order before the ASN and invoice are built, because a short pick reported honestly on day one is a manageable conversation, and the same short pick discovered by the buyer at receiving is a chargeback.

— Chris, founder of SignalEDI