Reference·PER Segment·PER01
X12 278 Reference

X12 278 PER01 (Contact Function Code): Format, Values, and Testing Notes

Jul 28, 2026 · 4 min read
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PER01 has a real code list behind it, but in practice a 278 transaction almost always sends the same value — which makes it easy to hardcode a parser against that one case and never notice until a trading partner sends something else.

Quick answer

PER01 is a code in the PER segment of an X12 278 that identifies what function the named contact serves — in prior authorization transactions this is overwhelmingly IC, meaning information contact, the person to reach with a general question about the request.

Valid code values

IC
Information Contact — the standard value in a 278 — the person to call with a question about the request or response
BL
Billing Contact — occasionally used when a separate billing office needs to field questions
CN
General Contact — a catch-all for a contact that doesn't fit a more specific role

Example

Synthetic example Generated by Synthibase
PER*IC*A JOHNSON*TE*8005557321*EX*4482

PER01 is IC here, marking A Johnson as the general information contact for this request. Synthetic test data.

Where this trips people up

Because IC covers nearly every real-world case, some intake systems hardcode PER01 as a constant instead of reading it, and downstream logic never actually checks the value. That's fine until a trading partner sends BL for a billing-specific contact and the request gets routed to the wrong desk — a failure that only shows up once test data stops assuming IC is the only option.

How to Test X12 278 PER: A Field-by-Field Breakdown
X12 278 Prior Authorization: Format, Fields, and Testing Guide
Prior Authorization Reform: CMS-0057-F and State Gold-Carding Laws Explained
Test beyond the one code value you always see
Synthibase varies PER01 and other situational codes across synthetic 278 transactions so intake logic gets exercised against more than the single value that happens to dominate production traffic.
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This page is written independently by Synthibase for testing and informational purposes. It is not an official publication of HL7 International or X12/Washington Publishing Company, and is not a substitute for reviewing the official standard or your trading partner's companion guide. See our Terms of Service for full legal terms.