# EDI 855 (Purchase Order Acknowledgment)

> Source: https://netray.co/glossary/edi-855-po-acknowledgment
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Glossary

## Short answer

The EDI 855 is the X12 transaction set a supplier sends in reply to a customer's 850 purchase order. It states whether each line is accepted, changed or rejected, with the confirmed quantity, price and delivery date.

## Aliases

- X12 855
- PO acknowledgment
- order acknowledgement EDI
- POA

## Category

integration

## Full Definition

The 855 is a business-level reply, different from the 997 or 999 functional acknowledgment. The 997 only says the file was received and syntactically valid. The 855 says what the supplier will actually do with the order. A customer can have a perfectly valid 997 and still receive an 855 that rejects half the lines.

The BAK segment in the header sets the status for the whole order, and ACK segments at line level state the status per line. Typical codes are accepted without change, accepted with changes, and rejected. When the supplier changes something, the 855 carries the new quantity, price or date so the customer's buyer can see the difference against the original PO.

In ERP terms, the 855 is produced when a customer order is entered or confirmed. In SyteLine this is the Customer Order line with its promise date and release status. In NetSuite it is the sales order after approval. In Infor LN it is the sales order line with its confirmed delivery date. A common design is to create the sales order automatically from the 850, then send the 855 after credit and availability checks complete.

Not every customer asks for an 855, and some accept silence as agreement. Where it is required, an automated 855 prevents the buyer from chasing status by phone and gives the customer an early warning of late delivery, which feeds their own planning.

## Why It Matters

- It gives the customer an early, structured warning when a delivery date or price will differ from the PO.
- Automating it reduces order status calls and emails to the customer service team.
- It exposes whether the supplier's ERP actually confirms dates from real availability or just copies the requested date.
- Some OEM scorecards measure acknowledgment timeliness and accuracy.

## In Practice

A customer sends an 850 for 1,000 pieces due on the 15th. The supplier's order entry runs availability and finds 800 pieces can ship on the 15th and 200 on the 22nd. The 855 returns line 1 as accepted with changes, with two schedule lines. The customer's buyer sees the split in their PO screen and can decide to expedite the balance or accept it.

## Faq

### What is the difference between an 855 and a 997?

**Answer:** A 997 or 999 only confirms the file arrived and was valid. The 855 is the supplier's business reply that accepts, changes or rejects the order.

### Is the 855 mandatory?

**Answer:** It depends on the trading partner's guide. Many customers require it, others do not.

### What is the 865?

**Answer:** The 865 is the Purchase Order Change Acknowledgment, sent in reply to an 860 PO change request, while the 855 replies to the original 850.

### Which ERP data drives the 855 dates?

**Answer:** The confirmed promise or ship date on the customer order line. If that date is only a copy of the request date, the 855 adds no information.

## Search terms

EDI 855, purchase order acknowledgment EDI, 855 vs 997, X12 855 codes, PO acknowledgement automation, EDI 855 SyteLine, 855 accept with changes, order acknowledgment EDI

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