To start and identify an interchange of zero or more functional groups and interchange-related control segments
Walmart X12 855 Purchase Order Acknowledgment
X12 855 (Purchase Order Acknowledgment) is the EDI transaction exchanged between Walmart (Sam's Club) and its trading partners. Stacksync handles full compliance, mapping, and real-time delivery.
- Segments
- 12
- Loops
- 5
- X12 855
- All partners ↗
Transaction context
Where 855 Purchase Order Acknowledgment fits on Sam's Club
On Sam's Club, the X12 855 Purchase Order Acknowledgment follows the 850 Purchase Order and precedes the 856 Ship Notice Manifest and 810 Invoice in the Order-to-cash cycle.
- Walmart channels
- 3 of 8
- Trading partners
- 269
- Channels
- 328
3 of Walmart's 8 channels carry 855
partners across the Stacksync network trade 855
channels network-wide carry 855
Most common alongside 855
The 855 is the seller's formal response to an 850 purchase order: accept as submitted, accept with changes to price, quantity, dates, or items, or reject. Buyers require it to confirm the order is committed before shipment and to surface availability, pricing, and item discrepancies while there is still time to correct them. Many retail compliance programs mandate it within a defined window, commonly 24 to 48 hours of PO receipt, and failure to send required response documents on time can result in financial penalties under vendor compliance programs. Sent by the supplier or vendor to the buyer that issued the purchase order.
When it fires: A supplier's order management system finishes validating an inbound purchase order against its item master, pricing, and available inventory.
Common 855 rejection causes
- Acknowledgments sent after the buyer's required response window, commonly 24 to 48 hours, exposing the supplier to compliance penalties.
- PO number or line references that do not match the original 850, so the buyer's system cannot tie the acknowledgment back to the order.
- Inaccurate product identifiers or prices echoed back on the acknowledgment, creating discrepancies that persist into the ship notice and invoice.
- Missing or inconsistent acknowledgment status codes, leaving the buyer unsure whether changed quantities, dates, or backorders were actually committed.
Specification summary
X12 855 Purchase Order Acknowledgment at the element level
The X12 855 specification defines 54 segments carrying 204 data elements, 72 of which are mandatory.
- Segments
- 54
- Data elements
- 204
- Mandatory elements
- 72
| Segment | Elements | Mandatory |
|---|---|---|
| BAK | 6 | 4 |
| CUR | 2 | 2 |
| REF | 3 | 1 |
| FOB | 3 | 1 |
| SAC | 10 | 1 |
| DTM | 4 | 1 |
| TXI | 7 | 1 |
| N9 | 3 | 1 |
| MSG | 2 | 1 |
| N1 | 4 | 1 |
| N2 | 2 | 1 |
Key identifiers in 855
- Transaction Set Purpose Code
- Acknowledgment Type
- Purchase Order Number
- Date
- Entity Identifier Code
- Currency Code
- Reference Identification Qualifier
- Shipment Method of Payment
Full segment guideline — 12 segments 5 loops · X12 855 Purchase Order Acknowledgment
To indicate the beginning of a functional group and to provide control information
To indicate the start of a transaction set and to assign a control number
To indicate the beginning of the Purchase Order Acknowledgment Transaction Set and transmit identifying numbers and dates
To specify identifying information
N9 Loop Repeat: 1,000
To transmit identifying information as specified by the Reference Identification Qualifier
N1 Loop Repeat: 200
To identify a party by type of organization, name, and code
PO1 Loop Repeat: 100,000
To specify basic and most frequently used line item data
ACK Loop Repeat: 104
To acknowledge the ordered quantities and specify the ready date for a specific line item
To specify pertinent dates and times
CTT Loop Repeat: 1
To transmit a hash total for a specific element in the transaction set
To indicate the end of the transaction set and provide the count of the transmitted segments (including the beginning (ST) and ending (SE) segments)
Trading partners
2+ trading partners.
And every channel covered.
We connect to every major retailer, distributor, and 3PL on the EDI network. Type to search the directory, or browse the full catalogue.
No trading partner matches your search.
Browse the full directory
Trading partners
4+ trading partners.
And every channel covered.
We connect to every major retailer, distributor, and 3PL on the EDI network. Type to search the directory, or browse the full catalogue.
No trading partner matches your search.
Browse the full directory
Walmart Sam's Club EDI 855 FAQ
Common questions about 855 Purchase Order Acknowledgment on the Sam's Club channel.
What is X12 855 Purchase Order Acknowledgment?
X12 855 (Purchase Order Acknowledgment) is the EDI transaction set used to exchange purchase order acknowledgment data. Walmart's Sam's Club channel requires it from trading partners.
Does Walmart Sam's Club require 855 for trading partners?
Yes, Walmart (Sam's Club) supports X12 855 Purchase Order Acknowledgment. Stacksync handles the full integration so your team can focus on operations.
How fast can I integrate Walmart 855 with Stacksync?
Most companies go live with Walmart 855 on Stacksync in days. Pre-built mappings, no-code setup, and real-time monitoring make EDI compliance straightforward.
Which other Walmart channels accept 855?
X12 855 runs on 3 of Walmart's 8 channels. Besides Sam's Club, it is accepted on Walmart US (Goods for Resale), Walmart Drop Ship Vendor via SPS. Each channel carries its own implementation guideline; Stacksync validates outbound documents against the correct guideline automatically.
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