CN HCPCS Level II modifier: 100 percent impaired, limited or restricted
CN is a HCPCS Level II modifier: “100 percent impaired, limited or restricted.” It adds this detail to the code it is reported with.
Official description
CN100 percent impaired, limited or restricted
Short description: 100 percent impaired, ltd
HCPCS · United States
Notes for CN
As CMS prints them, with any note CN takes from the headings above it.
Note
- CMS processing note 0180: 2013 PFS; PUB 100-04, 5-10, 12.027I.
Medicare details
The indicators CMS publishes with CN in its October 2026 file. They describe Medicare’s handling, not another payer’s.
- Medicare coverage
- Special coverage instructions apply
- Added
- Jan 1, 2013
Where CN sits
- 1GroupHCPCS modifiers
- 2Modifier CN100 percent impaired, limited or restricted
Source and release
- Data release
- HCPCS Level II · October 2026
- Effective date
- Oct 1, 2026
- Publisher
- CMS
This page is built from the HCPCS Level II catalog that Vero Codes reads when it suggests codes: Centers for Medicare & Medicaid Services’s October 2026 release, imported from the publisher’s file and checked against it. The description, notes and structured data come from the same record.
Frequently asked questions
What does HCPCS code CN mean?
CN is the HCPCS code for “100 percent impaired, limited or restricted” in CMS’s HCPCS Level II October 2026 release.
Where is CN in the HCPCS Level II list?
CN is listed under Modifiers.
Does Medicare cover CN?
CMS lists CN’s Medicare coverage as “Special coverage instructions apply”. Coverage and payment still depend on the patient, the setting, the documentation and the payer.
Which HCPCS Level II release does this page use?
It uses CMS’s October 2026 release, in effect from Oct 1, 2026 to Dec 31, 2026. It is a reference: confirm the code against the current list and the payer’s rules before you submit it.
Codes beside CN
All modifiersCH0 percent impaired, limited or restrictedCIAt least 1 percent but less than 20 percent impaired, limited or restrictedCJAt least 20 percent but less than 40 percent impaired, limited or restrictedCKAt least 40 percent but less than 60 percent impaired, limited or restrictedCLAt least 60 percent but less than 80 percent impaired, limited or restrictedCMAt least 80 percent but less than 100 percent impaired, limited or restrictedCOOutpatient occupational therapy services furnished in whole or in part by an occupational therapy assistantCPAdjunctive service related to a procedure assigned to a comprehensive ambulatory payment classification (c-apc) procedure, but reported on a different claimCQOutpatient physical therapy services furnished in whole or in part by a physical therapist assistantCRCatastrophe/disaster relatedCSCost-sharing waived for specified covid-19 testing-related services that result in and order for or administration of a covid-19 test and/or used for cost-sharing waived…CTComputed tomography services furnished using equipment that does not meet each of the attributes of the national electrical manufacturers association (nema) xr-29-2013 standard