The ICD-10-CM and PCS codes were released in June 2024. When ICD-10 codes are released, there are files posted on the Centers for Medicare and Medicaid (CMS) website. The files are separated by diagnosis (ICD-10-CM) and inpatient procedure (ICD-10-PCS). The ICD-10 codes are released semi-annually.
For the diagnosis codes, the files include Index, Tabular, Drug, External Index, Neoplasm, and Order files. Each file also has a matching addendum which contains only the changes for FY25 (for this year).
The Index is the alphabetic listing of diagnoses with the corresponding codes.
The Tabular is the volume which lists the diagnosis codes in alphanumerical order. This volume also contains coding instructions for each chapter, category, subcategory, code, etc.
The Drug file lists the drugs/substances with the type of poisoning (accidental, intentional self-harm, assault, undetermined); adverse effect, and underdosing.
The External Cause Index is the alphabetic listing for external causes of injuries. The Neoplasm Table lists the anatomic sites of neoplasms by behavior – primary malignant, secondary malignant, carcinoma in situ, benign, uncertain behavior, and unspecified behavior.
The order file is usually used by programmers or software developers as it includes categories, subcategories, and codes. In other words, it lists valid and invalid codes.
The ICD-10-CM guidelines were updated for October 2024. The changes in the guidelines are identified with bold text (narrative\changes), underline (moved within the guidelines), and italics (revisions to heading changes).
The ICD-10-PCS code update includes definitions addenda, tables addenda, PCS update summary, and PCS. The definitions addenda include changes to the PCS characters 3 through 7. The key provides guidance for specific body parts, substances, root operations and the corresponding value in the code set. The tables addenda contain only the changes in the PCS tables. The table rows that have changed are identified. The specific change is not noted.
The PCS Update Summary provides a quick review of the overall changes, changes to the guidelines, and a list of the associated files. This document also includes a listing of each section and the total number of codes now in that section. The PCS file contains the Index and Tables for ICD-10-PCS. This file is like an electronic version of the ICD-10-PCS codebook.
The ICD-10-PCS guidelines will also be updated usually. For FY25, there were no updates to the guidelines, but a FY25 version was included in the files.
The files for ICD-10-CM and ICD-10-PCS are free resources that are available.
It is important for coders to understand how the classification works without an encoder. These resources are wonderful to practice the classifications without spending money.
FY25 is right around the corner!
Resources:
ICD-10-CM FY25: https://www.cms.gov/medicare/coding-billing/icd-10-codes/2025-icd-10-cm
ICD-10-PCS FY25: https://www.cms.gov/medicare/coding-billing/icd-10-codes/2025-icd-10-pcs