CO-190 means the payer won’t pay you separately because the service is already covered by a skilled nursing facility (SNF) stay. Under SNF consolidated billing, the facility bills for most services its Part A residents get, even when an outside supplier provides them. So a lab, imaging company or therapy group that bills the plan directly gets CO-190. The money has to come from the SNF instead. (Primary source: X12 Claim Adjustment Reason Codes)
In brief: CARC 190 reads “Payment is included in the allowance for a Skilled Nursing Facility (SNF) qualified stay.” Check whether the service is excluded from consolidated billing. If it’s excluded, bill it correctly, such as the professional component only. If it’s included, bill the SNF under your arrangement, and the SNF puts it on its own claim.
Part of our denial codes library. Written by Manikandan J, CPC, CRCR, who has worked SNF consolidated billing edits for radiology and lab suppliers. Published 22 October 2026. Last updated: 22 October 2026. Code wording quoted word for word from X12.
Official CARC 190 description
| Field | X12 text |
|---|---|
| Code | 190 |
| Description | “Payment is included in the allowance for a Skilled Nursing Facility (SNF) qualified stay.” |
| Start | 10/31/2005 |
Source: X12 Claim Adjustment Reason Codes, checked 22 October 2026.
How SNF consolidated billing works
Consolidated billing is the Medicare rule that makes the SNF responsible for billing almost all services a resident gets during a covered Part A stay. A qualified stay is a covered SNF stay, usually after a qualifying hospital stay. Outside suppliers must look to the SNF for payment. Some services are excluded, which means they’re billed separately, such as most physician professional services and the professional component of diagnostic tests. CMS keeps the details on its SNF consolidated billing page. Many Medicare Advantage plans apply the same rules.
Example scenario (fictional names), part 1
CO-190 Denial Example: What Happened
Ruth Kowalski bills for Evergreen Mobile X-Ray, which also employs a radiologist, Dr. Thomas Nguyen. The company did a two-view chest X-ray (71046) at a skilled nursing facility for suspected pneumonia (J18.9), and Dr. Nguyen read it. The claim went to Silver Oak Senior Plan, a fictional Medicare Advantage plan, as one global 71046 line with place of service 31.
The 835 showed CAS*CO*190 with remark LQ*HE*N106, “Payment for services furnished to Skilled Nursing Facility (SNF) inpatients (except for excluded services) can only be made to the SNF.”
Was the whole X-ray really the SNF’s to pay, or only part of it? Keep reading, or jump to how the CO-190 denial was resolved.
What triggers reason code 190
- Global billing for a diagnostic test. For example, a supplier bills the full test when only the reading is excluded.
- Outside supplier billing the plan. Labs, imaging, supplies and therapy billed directly while the patient is in a covered stay.
- Dates overlap the stay. The claim date falls inside the SNF stay, even if the supplier didn’t know the patient was admitted.
- Wrong place of service. The claim shows a setting that doesn’t match where the patient actually was.
How to fix a CO-190 denial
- Confirm the stay. Ask the SNF for the admission and discharge dates and whether the stay is covered.
- Check the exclusion lists. Physician professional services, the professional component of tests and some high-cost services are billed outside the SNF claim.
- Split what you can. Bill the excluded part yourself, such as the reading with modifier 26.
- Bill the SNF for the rest. The technical part goes on your invoice to the SNF under your agreement. The SNF reports it on its own claim.
- Send a corrected claim with frequency code 7 for the excluded part.
- Prevent repeats. Ask facilities for a census of covered residents and check it before billing.
Example scenario (fictional names), part 2
How the CO-190 Denial Was Resolved
Ruth checked with the facility. The patient was in a covered SNF stay on the date of the X-ray. The technical part of the X-ray was part of the SNF’s payment, but Dr. Nguyen’s reading was excluded from consolidated billing.
Fix: Ruth sent a corrected claim with Box 22 code 7 showing 71046-26, the professional component only. She invoiced the facility for the technical part under their service agreement, and the SNF added the chest X-ray to its own claim.
Outcome: Silver Oak paid the reading, and the SNF paid Evergreen for the technical part. Evergreen now checks every facility’s census before billing.
Names and details are illustrative; no real patient data.
- Box 24D modifier: 71046 billed globally changed to 71046-26 (professional component), which is excluded from SNF consolidated billing.
- Box 22: frequency code 7 with the original claim number.
- FL 42 / FL 44 (SNF claim): the technical chest X-ray reported by the SNF with revenue code 0324 and 71046; type of bill 0217 in FL 4 with FL 64.
- Box 21 / FL 67: J18.9, entered as J189, is unchanged. Charges are placeholders.
CARC 190 vs related codes
| Code | What it says | Key difference |
|---|---|---|
| CO-190 | Included in a SNF qualified stay | SNF must pay |
| CO-97 | Included in another service | Bundled with another service on the claim |
| CO-109 | Not covered by this payer/contractor | Wrong payer entirely |
| CO-18 | Exact duplicate claim/service | Billed twice |
Prevention checklist
- Get a weekly census of covered residents from each facility you serve.
- Bill diagnostic tests in two parts for SNF patients: the reading to the plan, the technical part to the SNF.
- Keep a written agreement with each SNF that says how you’ll bill them.
- Read the RARC. N107, “Services furnished to Skilled Nursing Facility (SNF) inpatients must be billed on the inpatient claim.” means the SNF must add the service to its claim.
Recap
CO-190 means the service is paid through the SNF’s stay. Check the stay dates and the exclusion lists. Bill excluded parts such as the professional reading yourself, and bill the SNF for the rest. Then the SNF adds those services to its own claim.
FAQ
What does CO-190 mean?
The payer says the service is included in the payment for a skilled nursing facility qualified stay, so it can’t be paid separately.
Who pays for a service denied with CO-190?
Usually the SNF, under its agreement with the supplier. The SNF then bills the plan on its own claim.
Are physician services included in SNF consolidated billing?
Most physician professional services are excluded and billed separately. The professional component of a diagnostic test is excluded too.
Can I bill the patient for a CO-190 line?
No. Group code CO and consolidated billing rules keep it off the patient’s bill.
Does CO-190 apply to Medicare Advantage plans?
Many Medicare Advantage plans follow the same rules. Check the plan’s provider manual.
What place of service code is a skilled nursing facility?
Place of service 31 is a skilled nursing facility, and 32 is a nursing facility.
Sources
How we checked: each code quote on this page was matched word for word with the X12 CARC and RARC lists on 22 October 2026.
- X12, Claim Adjustment Reason Codes (CARC 190, 97, 109, 18). Accessed 22 Oct 2026.
- X12, Remittance Advice Remark Codes (N106, N107). Accessed 22 Oct 2026.
- CMS, SNF consolidated billing. Accessed 22 Oct 2026.
- CMS, Medicare Claims Processing Manual, Chapter 6 (SNF inpatient Part A billing). Accessed 22 Oct 2026.
- CMS, Place of Service code set. Accessed 22 Oct 2026.
Last updated: 22 October 2026 · Educational content; not legal advice.
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