ICD-10-CM Code Updates for FY 2027

The FY 2027 ICD-10-CM update adds 190 new diagnosis codes and revises 4 existing code descriptions, effective October 1, 2026. The update brings the tabular list to 74,879 codes. This page breaks the release down chapter by chapter and lists every changed code, with a filter to find the ones that matter to you.

Where the New Codes Landed

New codes are never spread evenly across the classification. Each release concentrates on the clinical areas where CMS and NCHS accepted proposals for greater specificity, and FY 2027 is no exception: the top two chapters account for 55% of all additions.

The table below covers every chapter in the classification, including the ones this release left untouched.

Total Codes is the complete FY 2027 tabular count for each chapter as loaded in the ICD List database, including non-billable header categories. New and Revised counts come from the official release addenda.

What Changed: the Big Themes

The chapters below saw the most movement in the FY 2027 release. Counts and example codes come straight from the official release files.

Injury & poisoning (S00–T88)

This chapter received 60 of the 190 new diagnosis codes in the release, 32% of all additions. New codes include T52.811A (Toxic effect of alkenes, accidental (unintentional), init), T52.811D (Toxic effect of alkenes, accidental (unintentional), subs), and T52.811S (Toxic effect of alkenes, accidental (unintentional), sequela).

Every injury-chapter addition this year is a toxic effect code. Four substances get their own subcategories: alkenes (T52.81-) and cycloparaffins (T52.82-), which replace the single other organic solvents subcategory T52.8X- (its 12 codes are deleted; other organic solvents moves to T52.89-), hexamethylene diisocyanate (T59.82-), and the sedative medetomidine (T65.85-). Each substance carries the four intents (accidental, intentional self-harm, assault, undetermined) times the initial encounter, subsequent encounter and sequela 7th characters, which is why one new substance adds 12 codes. The medetomidine codes carry a Use Additional Code note for manifestations such as bradycardia (R00.1) and somnolence, stupor and coma (R40.-). The chapter also loses the three S23.420- codes for sprain of the sternoclavicular joint under the thorax category; sternoclavicular sprains are reported with S43.61 and the rest of S43.6-.

Pregnancy & childbirth (O00-O9A)

This chapter received 44 of the 190 new diagnosis codes in the release, 23% of all additions. New codes include O00.121 (Right interstit ectopic pregnancy without uterin pregnancy), O00.122 (Left interstit ectopic pregnancy without uterin pregnancy), and O00.129 (Unsp interstit ectopic pregnancy without uterin pregnancy).

Ectopic pregnancy is now coded by implantation site. New codes cover interstitial (O00.121 through O00.139), cesarean scar (O00.31, O00.32), cervical (O00.41, O00.42) and cornual (O00.511 through O00.529) pregnancies, each split by whether an intrauterine pregnancy is also present, and by side for interstitial and cornual sites. The other 28 codes create subcategory O31.4, continuing pregnancy after vanishing twin syndrome of one fetus or more, with the trimester in the 5th character and the affected fetus in the 7th, starting at O31.40X0.

Musculoskeletal system (M00–M99)

This chapter received 31 of the 190 new diagnosis codes in the release, 16% of all additions. New codes include M04.3 (VEXAS syndrome), M67.A01 (Plantar fasciitis, right foot), and M67.A02 (Plantar fasciitis, left foot).

Most of the musculoskeletal additions give other osteomyelitis laterality. The site codes M86.8X1 through M86.8X8 are now subcategories with right, left and unspecified codes (skull, face and sinuses, and other site for M86.8X8), so a code such as M86.8X1 is no longer billable on its own; start at M86.8X11. Plantar fasciitis gets its own subcategory, M67.A01 through M67.A09, plantar fascial fibromatosis is split by foot (M72.20 through M72.22), and M04.3 adds VEXAS syndrome to the autoinflammatory syndromes.

Health status factors (Z00–Z99)

This chapter received 16 of the 190 new diagnosis codes in the release, 8% of all additions. New codes include Z68.18 (Body mass index [BMI] 18.4 or less, adult), Z68.19 (Body mass index [BMI] 18.5-19.9, adult), and Z77.013 (Contact with and (suspected) exposure to gadolinium). It also carries 1 of the 4 revised code descriptions.

The Z-code additions capture exposures that matter in veterans' care: burn pits in a war theater (Z77.32), Agent Orange (Z77.33) and blast overpressure at unspecified, low, high and other levels (Z77.40 through Z77.49), plus gadolinium exposure (Z77.013), which pairs with the new abnormal blood gadolinium finding R78.72. Personal history of sex reassignment (Z87.890) is replaced by codes for social, medical and surgical gender transition, intersex surgery and unspecified transition (Z87.8901 through Z87.8909), with Z87.893 for gender detransition. Adult BMI 19.9 or less is split into 18.4 or less (Z68.18) and 18.5 to 19.9 (Z68.19), and Z86.17 adds a personal history of Clostridioides difficile infection.

Notable changes beyond the biggest chapters

Cardiology gains specificity: dilated cardiomyopathy is split into unspecified, familial-genetic and other (I42.00 through I42.09), arrhythmogenic cardiomyopathy gets I42.81, and named arrhythmias get their own codes, including catecholaminergic polymorphic ventricular tachycardia (I47.22), Brugada syndrome (I49.81) and ventricular bigeminy (I49.82). A new category, QA1, covers genetic disorders associated with neoplasms, with codes for Lynch syndrome (QA1.71), familial cancer syndromes with pathogenic BRCA1 and BRCA2 mutations (QA1.790, QA1.791) and Li-Fraumeni syndrome (QA1.792), and Loeys-Dietz syndrome gets Q87.A.

Other single additions include odontogenic sinusitis by sinus (J34.830 through J34.839), pulmonary mycetoma (J4B), hypertrophic pyloric stenosis in childhood (K31.B), intestinal failure-associated liver disease (K76.83), post bariatric hypoglycemia (E89.830), Glanzmann thrombasthenia (D69.11), and secondary malignant neoplasms of the larynx, pharynx and oral cavity (C78.31, C78.32, C79.83). Four codes were revised: the carbuncle, cellulitis and acute lymphangitis of back codes (L02.232, L03.312, L03.322) now exclude the flank as well as the buttock, alongside the new L02.237 for carbuncle of flank, and Z29.14 was retitled.

All 224 FY 2027 Code Changes

Every changed code in the FY 2027 release is listed below, grouped by change type and chapter, and each code links to its detail page. Type a code or keyword in the filter to narrow the lists; sections with matches expand automatically.

How FY 2027 Compares to Past Years

The code set grows a little almost every year. The chart covers every annual release in the ICD List archive; hover over a bar for the exact totals, the effective window, and the change counts where available.

Complete year-by-year totals are also on our About page.

FY 2027 Update FAQ