Every buyer that transmits an 850 purchase order is waiting on the same question: will you ship it, all of it, on time? The EDI 855 Purchase Order Acknowledgment is your answer. It confirms — line by line — what you can fulfill, what is backordered, what you are rejecting, and what you are changing. Sent quickly and honestly, it is the cheapest customer-service document in the X12 catalog. Sent late or wrong, it turns into shortages the buyer discovers at the receiving dock.
What the 855 commits you to
An 855 is not a courtesy note; buyers treat it as a commitment. The header BAK segment identifies the PO being answered and carries an acknowledgment type — acknowledged with no changes, acknowledged with changes, or rejected. The detail loop echoes the PO lines, and ACK segments attach a status to each one: accepted, backordered, rejected, or accepted with a modification to quantity, price, or date.
That line-level granularity is the whole point. Distributors in particular run on it: McKesson expects an accept, backorder, or reject code on every single line, and a backordered line must carry a revised availability date — an open-ended hold reads as a cancel. Amazon expects a line-level accept or reject on its POs within 24 hours. A header-level "order received, thanks" satisfies neither.
The clock starts when the 850 lands
Turnaround expectations vary by industry, but the direction is uniform: fast. Pharmaceutical replenishment cycles are measured in hours, so McKesson wants same-day acknowledgment. Broadline food distributors and grocery chains run similar same-day rhythms on replenishment orders. Retail programs generally tie the acknowledgment window into their vendor scorecards.
The practical consequence: an 855 process that depends on a human opening the order, checking stock, and keying a response cannot keep up. The acknowledgment has to be generated from live availability data in your ERP — which is exactly what makes it automatable, since everything the 855 needs (on-hand, allocations, lead times) already exists in your system.
Where acknowledgments go wrong
Three patterns account for most 855 trouble:
- The optimistic acknowledgment. Accepting every line by default, then short-shipping. The buyer planned shelf space and labor against your confirmation; the gap surfaces as a fill-rate problem and often a deduction.
- The silent change. Shipping a different quantity or date than you acknowledged without sending an updated 855 or responding to the buyer's 860 change request. Downstream, the 856 ship notice no longer matches anything.
- The vague backorder. Marking lines backordered with no recovery date. Buyers cannot plan against "eventually," and several distributors explicitly treat it as a rejection.
The common fix is the same: acknowledge from real data, and keep the acknowledgment synchronized with what fulfillment actually does. It helps to remember who reads the document — an 855 feeds the buyer's replenishment engine directly, so a wrong status doesn't just misinform a person; it propagates into forecasts and store allocations before anyone can catch it.
Generating 855s automatically
EDISQ builds the 855 from the order record it just created in your ERP — NetSuite, or any of the 30+ systems we integrate. The inbound 850 lands as a sales order with items and ship-tos cross-referenced; availability drives the line statuses; the 855 transmits back within the partner's window without anyone touching a portal. Partner-specific rules (which status codes a buyer accepts, whether substitutions are allowed) live in the certified map.
Cost-wise, the acknowledgment rides the same meter as every other document on EDISQ's pricing: your first 25 documents in a month are free, and beyond that each one starts at $0.50 and steps down with volume to $0.30 at the highest tier — billed marginally, with AS2, SFTP, and VAN connectivity all included. There is no subscription underneath it and no charge per trading partner, so acknowledging every PO on time never becomes a line item worth debating.
If your buyers are already complaining about acknowledgment speed, start with the transaction glossary to see how the 855 fits the full order-to-cash chain — then check your specific partners' expectations in our partner directory.
FAQ
What is the difference between an 855 and a 997?
The 997 says the file arrived and parsed; the 855 says what you will actually do about the order. A PO can be acknowledged by a 997 and still need an 855 with line-level accept, backorder, or reject status.
Is the EDI 855 required?
Most large buyers require it on every PO, and several enforce turnaround windows. Even where optional, skipping it means the buyer plans against quantities you may not ship.
Can an 855 change quantities or dates?
Yes — that is its job. Line status codes let you accept, reject, backorder, or accept with changes, so the buyer learns about shortages before the truck does.
How is the 855 priced with EDISQ?
One outbound 855 is one document: the first 25 documents each month are free, then from $0.50 per document, decreasing with volume. No per-partner or mapping fees.