ORC-3 in HL7 v2: A Field Guide to Filler Order Number
A new order often leaves ORC-3 blank because the filler hasn't assigned a number yet, and systems that assume the field is always populated break the moment they process the very first message of an order's lifecycle.
ORC-3 is the third field of the HL7 v2 ORC segment — the performing (filler) system's own identifier for the order, typically assigned once the receiving system accepts the request. Like ORC-2, it is expected to match the corresponding OBR-3 value whenever both segments appear together.
What this field contains
Example
FIL98831^SYNTHIB in the third field is the filler order number, assigned once the performing system accepts the order. Synthetic order number — not from a real facility.
Where this trips people up
Because ORC-3 is legitimately empty on a brand-new order and only gets populated once the filler confirms it, test suites that always populate it on every message never exercise the empty-then-populated transition that real order lifecycles go through. The other recurring issue is the same one that affects ORC-2: if OBR-3 is generated independently of ORC-3 rather than copied from it, a mismatch between the two can slip through review and only surface when a downstream system tries to match a result back to its order and finds two different filler numbers pointing at what's supposed to be the same request.