2026 ICD-10-CM Diagnosis Code R91Abnormal findings on diagnostic imaging of lung

ICD-10-CM Codes›R00–R99›R90-R94›R91

ICD-10-CM R91
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R91 is a non-billable ICD-10-CM category code for abnormal findings on diagnostic imaging of lung, so it cannot be submitted on claims. Use a more specific code from this category instead, such as R91.1 and R91.8. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established.

Code Identity

ICD-10-CM Code
R91
Billable Status
No — Non-Billable Category
Code Describes
Abnormal findings on diagnostic imaging of lung
Chapter
R90-R94
Abnormal findings on diagnostic imaging and in function studies, without diagnosis

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR90-R94Abnormal findings on diagnostic imaging and in function studies, without diagnosis
CategoryR91Abnormal findings on diagnostic imaging of lung
This CodeR91Abnormal findings on diagnostic imaging of lung

Specific Coding for Abnormal findings on diagnostic imaging of lungOverview

Non-specific codes like R91 require more characters. Use one of these billable codes instead:

  • Use R91.1 for Solitary pulmonary nodule

  • Use R91.8 for Other nonspecific abnormal finding of lung field

Code HistoryHistory

  • FY 2026 - No Change, effective from 10/1/2025 through 9/30/2026
  • FY 2025 - No Change, effective from 10/1/2024 through 9/30/2025
  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.