On October 1, 2025, the Centers for Medicare & Medicaid Services (CMS), National Center for Health Statistics, and Centers for Disease Control and Prevention (CDC) revised the ICD-10-CM Official Guidelines for Coding and Reporting, as well as the code set. 

The updates to the guidelines for coding and reporting using the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) system include 487 new codes and 38 revised codes. Twenty-eight codes have been deleted.¹ Also, there are several revisions and additions to, as well as deletions from, the Alphabetic Index and Tabular List related to spelling corrections and grammatical and punctuation changes. Adjustments were made to instructional notes and guidance, as well. The ICD-10-CM Official Guidelines for Coding and Reporting added to the conventions for the ICD-10-CM and provide new general and chapter-specific coding guidelines.

Providers, coders, and payers must be aware of these essential ICD-10-CM updates because they support high-quality patient care while ensuring precise documentation and reimbursement. This article highlights the fiscal year (FY) 2026 changes most likely to impact the long term care setting that relate to conventions, general and chapter-specific coding guidelines, and the revised type 2 diabetes mellitus and multiple sclerosis codes. Staying informed about these revisions is key to optimizing clinical care and maintaining compliance with coding requirements.

Conventions, General Coding Guidelines, and Chapter-Specific Coding Guidelines

The conventions for the ICD-10-CM rarely change, but this year offers new guidance about the use of the comma in the Alphabetic Index: “Commas are used in the Alphabetic Index and have different meanings based on the context of the Index entry, including alternate verbiage, modifier (essential and nonessential), or alternative for ‘and/or.’”² 

The general coding guidance provides new instruction on “multiple sites,” stating if the medical record identifies the specific sites, a separate code is assigned for each site. If the sites are not specified, the code for “multiple sites” is used.

Chapter-specific coding guidance for chapter 13, “Diseases of the Musculoskeletal System and Connective Tissue” (M00–M99), includes this same coding guidance about “multiple sites.” Other updates to the chapter-specific coding guidelines include additional guidance on selection and sequencing of HIV codes; information on the new code E11.A, Type 2 diabetes mellitus without complications in remission; and clarification on which codes to include in the “hypertension with heart disease” category. The full coding guidance can be reviewed in the ICD-10-CM Official Guidelines for Coding and Reporting.²

E11.A Type 2 Diabetes Mellitus without Complications in Remission

During the March 2024 ICD-10 Coordination and Maintenance Committee meeting, held by the CDC twice a year, a proposal was made to add an ICD-10-CM code for patients with type 2 diabetes in remission. Per the citations in this proposal, patients are deemed in remission if they have sustained a normal blood glucose level for three months or more.³ Chapter-specific coding guidance for this new code states that “remission” is not synonymous with the term “resolved,” and thus, providers (physician and nonphysician extenders) must be queried for clarification. This new code is listed as an Excludes1 note at E11.9, Type 2 diabetes mellitus without complications, meaning both codes cannot be used at the same time. Additionally, E11.A cannot be coded with any type 2 diabetes with complications (E11.0–E11.8). 

Although the FY 2026 conversion table shows the old code as E11.9 and the new one as E11.A, not all patients with an E11.9 code as of September 30, 2025, must have this code changed to an E11.A code as of October 1, 2025.⁴ E11.9 is still a valid code for patients with type 2 diabetes without complications. Coders need to review the medical records of patients with type 2 diabetes to check for provider documentation that supports an “in remission” status to assign this new code. Physicians may be queried for further guidance and documentation if needed. Coders cannot make this decision independently based on blood glucose lab results; the documentation must come from the provider.

G35.-Multiple Sclerosis

At the September 2024 committee meeting, a revised presentation of a March 2023 proposal suggested adding ICD-10-CM codes for multiple sclerosis (MS) to “distinguish between different disease clinical courses, evaluation of disease progression and long-term prognosis of MS in large population-based epidemiological assessments.”⁴ These additions were approved for the FY 2026 code set, and the previous all-encompassing code of G35, Multiple sclerosis, was deleted. 

Eight more codes were substituted to reflect the different clinical subtypes:

• G35.A Relapsing-remitting multiple sclerosis
• G35.B0 Primary progressive multiple sclerosis, unspecified 
• G35.B1 Active primary progressive multiple sclerosis
• G35.B2 Non-active primary progressive multiple sclerosis
• G35.C0 Secondary progressive multiple sclerosis, unspecified 
• G35.C1 Active secondary progressive multiple sclerosis
• G35.C2 Non-active secondary progressive multiple sclerosis
• G35.D Multiple sclerosis, unspecified

All these codes were previously included under the broader code of G35. Coders must now review the medical record for evidence of the more specific MS subtypes and then choose one of the new codes to replace the obsolete G35 code. If the provider doesn’t cite a specific type of MS, a query may be needed. Or, lacking documentation of a specific MS type, patients with a G35 code must be converted to G35.D, Multiple sclerosis, unspecified. G35 is no longer a valid code as of October 1, 2025.

Next Steps for FY 2026 Codes

Accurate coding requires current resources, clear communication, and consistent review. Staff should update ICD-10-CM manuals every October and discuss the importance of precise diagnoses with medical directors and physicians. Physicians should also be prepared to respond to any coding queries. 

Each fiscal year, facilities must run diagnostic reports from the electronic health record to identify records with deleted or revised codes, using the CMS Conversion Table⁵ as a reference. Physician documentation can then be reviewed to determine the most appropriate updated codes. When additional details are needed, staff should contact the provider to ensure accuracy. By following these steps, health care teams can safeguard coding integrity, support high-quality resident care, and maintain compliance. 

Jennifer LaBay, RN, RAC-MT, RAC-MTA, QCP, CRC, is curriculum development specialist for the American Association of Post-Acute Care Nursing (AAPACN).