X12 segment reference
PO1 — Baseline Item Data
X12 PO1 segment reference for EDI 850 line items: quantity, UOM, unit price, and product ID qualifiers retailers require.
PO1 segment facts
- PO1 loops drive chargeback risk — quantity and UOM mismatches against the retailer catalog are a top ASN rejection cause.
- PO107 product ID qualifiers tell parsers whether PO109 carries a UPC, vendor SKU, or buyer item number.
- Validation rule packs can require PO102 quantity and PO103 UOM before an 850 leaves your sandbox.
What the PO1 segment does
PO1 repeats for each line on an 850. It binds quantity, unit of measure, pricing, and product identifiers (UPC, SKU, vendor part number).
Loop: Once per line item
Common transaction sets: 850
Key elements
| Element | Name | Description |
|---|---|---|
| PO102 | Quantity ordered | Numeric quantity; must match partner UOM expectations. |
| PO103 | Unit of measure | EA, CA, LB — retailer-specific allowed lists. |
| PO104 | Unit price | Often required for cost-based retailers; format varies. |
| PO107 | Product ID qualifier | UP, VN, SK — tells partners which ID type follows. |
Example PO1 segment
PO1*1*12*EA*9.99**UP*012345678905~
Parse and validate samples with the free EDI validator or send JSON via the JSON→X12 mapping guide.
Common PO1 errors
- Invalid UOM for the category
- UPC check digit failures
- Line sequence gaps when partners require contiguous PO101
Related reference
FAQ
Frequently asked questions
SignalEDI accepts JSON lines[] arrays; each object maps to one PO1 (and optional PID) iteration.