The 2027 ICD-10-CM code changes took effect on October 1, 2026, and apply to patient encounters through September 30, 2027. Coders, billers, accounts receivable (AR) staff, and practice managers need to use the diagnosis codes and guidelines applicable to each date of service. These updates can affect documentation, code selection, electronic health record (EHR) templates, superbills, and payer edits. For a detailed walkthrough, visit CareCloud’s ICD-10 2027 Updates Webinar: Code & Guideline Changes
FY 2027 ICD-10-CM Updates: Key Changes
The FY 2027 ICD-10-CM update includes 190 new codes, 30 deleted codes, and four revised codes, according to ACDIS’s summary of the FY 2027 code set. The official CMS ICD-10 page provides the updated code files and conversion table for verifying individual changes. These figures count code additions, deletions, and revised titles. They do not include every change to the Alphabetic Index, instructional notes, inclusion terms, or official coding guidelines.
The Centers for Disease Control and Prevention’s National Center for Health Statistics (CDC/NCHS) maintains ICD-10-CM, while the Centers for Medicare & Medicaid Services (CMS) publishes the official files and resources for implementation. CMS provides the FY 2027 Tabular List, code tables, addendum, conversion table, and coding guidelines.
The new ICD-10 codes for October 2026 are not simply additions to a reference list. They can change how a condition is represented on a claim, how documentation supports code selection, and how existing billing systems process diagnoses. Teams should review the complete official files rather than relying only on a summary of selected changes.
Notable New ICD-10-CM Codes for 2027
The new codes introduce more specific ways to classify certain conditions. Coders should confirm that the provider’s documentation supports the selected code and that the code is valid for the date of service.
New Codes For More Specific Diagnoses
For example, FY 2027 includes new codes for secondary malignant neoplasms of the larynx and pharynx:
- C78.31: Secondary malignant neoplasm of larynx
- C78.32: Secondary malignant neoplasm of pharynx
These codes distinguish the documented site of secondary malignancy. Coding teams should review the diagnosis documentation and confirm that the selected code accurately reflects the recorded condition.
New Codes For Postprocedural Conditions
The update also includes E89.830, Post-bariatric hypoglycemia, E89.838, and other postprocedural hypoglycemia. These codes make it important to distinguish the documented condition and its relationship to a procedure when assigning a diagnosis code. Coders should follow the applicable Tabular List instructions and official guidelines.
New Codes That Distinguish Location Or Laterality
FY 2027 adds more specific codes for conditions where the site or side matters. For example, J34.830 identifies odontogenic sinusitis of the maxillary sinus, while J34.831 identifies odontogenic sinusitis of the ethmoid sinus. The update also adds new codes for other sinus locations. These examples are not a complete list. Use the official CMS website to confirm code descriptions, billable status, and any applicable instructions before updating claim workflows.
FY 2027 ICD-10-CM Deleted Codes and Revised Codes
The FY 2027 code-level summary lists 30 deleted codes and four revised code titles. A revised code retains its number but has an updated description. Coders should check the new wording and confirm that the documentation still supports the code.
Deleted codes are no longer valid for reporting when the FY 2027 code set applies. For example, M72.2, Plantar fascial fibromatosis, is deleted and replaced by more specific codes: M72.20 for the unspecified foot, M72.21 for the right foot, and M72.22 for the left foot. The correct selection depends on the documentation.
Use CMS platform to identify deleted codes and their applicable replacements. Check the replacement’s full description and instructions in the current Tabular List.
A deleted code left in a superbill or EHR template can result in an invalid-code rejection or claim denial. Billing teams should remove outdated options, confirm replacements, update templates, and test the changes before continued use.
ICD-10-CM 2027 Guidelines: What Teams Need to Check
Code changes are only one part of the annual update. The FY 2027 ICD-10-CM Official Guidelines for Coding and Reporting also include revisions and clarifications that can affect code assignment and sequencing. The official guidelines should be used alongside the Tabular List and Alphabetic Index, not as a substitute for them.
Coding teams should review the sections most relevant to their specialties and services. The updated guidelines address areas including sepsis, cancer treatment, hypertension, genetic disorders, and Z codes.
Before applying a guideline change, confirm the full wording on the CMS official website. Then update internal coding references, audit checklists, and training materials where needed. This helps coders apply the same current guidance across documentation review and claim preparation.
Want the Code-by-Code Walkthrough?
Download the recording of CareCloud’s ICD-10 2027 Updates Webinar: Code & Guideline Changes to review the changes in detail.
Download 2027 ICD-10 Update
How to Prepare for ICD-10 Code Updates
Use this checklist to confirm that coding and billing workflows reflect the FY 2027 changes.
- Review superbills and templates. Remove deleted codes, update revised descriptions, and add relevant new codes. Check specialty-specific forms and frequently used diagnosis lists.
- Update EHR and practice management systems. Confirm that the FY 2027 code set is active for applicable dates of service. Check imported code tables and any saved favorites.
- Check payer edits. Review relevant claim edits and billing rules and verify requirements with payers when necessary. Do not assume every payer processes every change in the same way.
- Train coding and billing staff. Share the changes that affect your specialties, including code specificity, documentation requirements, and revised guidelines.
- Monitor denials and rejections. Track invalid or outdated diagnosis codes and identify whether an issue comes from a code table, template, documentation gap, or claim to edit.
- Audit a sample of claims. Review claims submitted after October 1, 2026, to identify recurring errors and confirm that updates are working as intended.
AR teams can help by grouping denials by reason and identifying patterns related to diagnosis coding. Not every denial is caused by an ICD-10-CM change, so investigate the payer’s response and correct the underlying issue before resubmitting.
Frequently Asked Questions
When do 2027 ICD-10 codes take effect?
FY 2027 ICD-10-CM codes took effect on October 1, 2026, and apply through September 30, 2027. Coders, billers, and practice managers should update diagnosis codes, coding guidelines, EHR systems, and billing templates to reduce coding errors and claim denials.
How many new ICD-10 codes are there for 2027?
The published FY 2027 code-level change summary lists 190 new codes, 30 deleted codes, and four revised code titles. These figures do not represent every change to guidelines or instructional notes.
What is the difference between new, revised, and deleted codes?
New codes add diagnosis classifications. Revised code titles keep the same code number but update the description. Deleted codes are no longer valid for reporting when the new code set applies, so coders should check the official conversion table for an appropriate replacement.
How should practices prepare for ICD-10-CM updates?
Review the official code files and guidelines, update EHR and billing templates, train staff, and monitor claims for coding-related rejections or denials. Use the documentation and date of service to determine the correct code.
