CO-206 — NPI Missing, Invalid, or Not Matched

Denial Identifier

• Primary CARCs: CO-206 — "National Provider Identifier - missing." CO-207 — "National Provider identifier - Invalid format." CO-208 — "National Provider Identifier - Not matched." (X12)
• Common RARCs: N433 ("Resubmit this claim using only your National Provider Identifier (NPI)."), N516 ("Records indicate a mismatch between the submitted NPI and EIN."), M68, MA102, N286/N290 (referring/rendering provider primary identifier), N277 (other payer rendering provider identifier)

Plain-Language Meaning

• The claim is missing an NPI where one is required, the NPI is not in a valid format, or the NPI submitted does not match the provider name/role on the payer's file (including PECOS ordering/referring records, where applicable).

Why the Claim Was Denied

• Claim construction: NPI field blank or malformed during claim creation/transmission
• Provider enrollment: ordering/referring provider's individual (Type 1) NPI is not enrolled in PECOS as required, or an organizational (Type 2) NPI was submitted where an individual NPI is required
• Registration/Claim construction: wrong provider's NPI entered (name/NPI mismatch)

Information the Biller Must Review

• Billing, rendering, referring, and ordering NPIs as applicable, NPI format validity, PECOS enrollment status for ordering/referring providers (individual NPI required — organizational NPIs do not qualify), name-to-NPI match against the NPPES registry.

What Needs to Be Corrected

• Claim correction: If the correct NPI exists but was omitted, malformed, or mismatched due to a data-entry/transmission error, correct and resubmit.
• Upstream correction: If the ordering/referring provider is not enrolled in PECOS at all, this is a Provider Enrollment issue — the referring physician (or NPP) must complete PECOS enrollment before the claim can be paid.

Resolution Workflow

• Identify which NPI role (billing/rendering/referring/ordering) triggered the denial from the CARC/RARC.
• Verify the correct NPI in NPPES and, for ordering/referring, in PECOS.
• If a claim-level data error, correct and resubmit.
• If the ordering/referring provider is not in PECOS, route to Provider Enrollment for PECOS enrollment; hold or appeal per payer timeline once enrollment completes.
• Document the NPI verification outcome.
• Escalate to Information Systems if NPIs are being dropped or truncated systemically during claim export.

Department Most Likely Responsible

• Resolves current claim: Billing/Follow-Up. Prevents recurrence: Provider Enrollment — PECOS enrollment verification for all ordering/referring providers; Information Systems — NPI field validation before claim export.

Prevention Control

• NPI validation against NPPES/PECOS at charge entry; claim-scrubber edit requiring individual NPI for ordering/referring fields; periodic PECOS-enrollment audit for all referring providers used by the practice.

Escalation Trigger

• Referring/ordering provider is a non-employed outside physician who is unresponsive to PECOS enrollment requests; systemic NPI field corruption in claim exports.

Sample Scenario

• Scenario: Lab claim denied CO-208/N286.
• Finding: Ordering physician's individual NPI does not appear in the CMS ordering/referring PECOS file.
• Action: Practice contacts the ordering physician's office to confirm/complete PECOS enrollment; claim held pending enrollment confirmation.

Resolution path at a glance

AI Search Terms / Synonyms

• CO206; CO207; CO208; NPI missing; NPI invalid; NPI not matched; PECOS denial; ordering referring NPI.

AI Answer Guardrail

• Confirm which specific provider role (billing/rendering/referring/ordering) triggered the NPI edit and verify PECOS enrollment status before recommending a correction or appeal.

Sources

• X12 CARC list; X12 RARC list; CMS Ordering & Certifying / PECOS