US · guidance
CMS Pub. 100-04, ch. 32, § 140.4.2.4
Edits for PR Services Exceeding 36 Sessions
When a beneficiary has reached 37 PR sessions, CWF shall reject the claims to the contractors if the KX
modifier is not included on the claim line. Effective for claims with dates of service on or after January 1, 2010,
Medicare contractors shall deny all claims (both professional and institutional claims) that exceed 36 PR
sessions without a KX modifier included on the claim line.
The following messages shall be used when Medicare contractors deny PR claims that exceed 36 sessions,
without the KX modifier on the claim line:
CARC 151: “Payment adjusted because the payer deems the information submitted does not support this
many/frequency of services.”
MSN 23.17: “Medicare won’t cover these services because they are not considered medically necessary.”
Spanish Version: “Medicare no cubrirá estos servicios porque no son considerados necesarios por razones
médicas.”
Contractors shall use Group Code PR (Patient Responsibility) assigning financial liability to the beneficiary, if a
claim is received with a GA modifier indicating a signed ABN is on file.
Contractors shall use Group Code CO (Contractual Obligation) assigning financial liability to the provider, if a
claim is received with a GZ modifier indicating no signed ABN is on file.
History
(Rev. 1966, Issued: 05-07-10, Effective: 01-01-10, Implementation: 10-04-10)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
60312933dafc273515d82e4448c2649cc90ef47b38a974403c60c0344f05df35
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