Diagnosis Coding

2026 ICD-10-CM Diagnosis Codes

The Clinical Modification (CM) system for classifying medical diagnoses across all healthcare settings in the United States.

A00-B99

Certain infectious and parasitic diseases

Covers diseases caused by bacteria, viruses, fungi, and parasites, including both acute and chronic infections. Used for classification and tracking o...
C00-D49

Neoplasms

Includes benign, malignant, and in situ neoplasms classified by anatomical site and behavior. Supports cancer diagnosis documentation, tumor tracking,...
D50-D89

Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism

Encompasses disorders of blood components and immune mechanisms, including anemia, clotting disorders, and immunodeficiencies. Used to classify hemato...
E00-E89

Endocrine, nutritional and metabolic diseases

Covers endocrine gland disorders, metabolic dysfunctions, nutritional deficiencies, and obesity. Essential for documenting chronic conditions such as ...
F01-F99

Mental, Behavioral and Neurodevelopmental disorders

Includes mental, behavioral, and neurodevelopmental disorders such as depression, anxiety, schizophrenia, and ADHD. Supports psychiatric diagnosis, tr...
G00-G99

Diseases of the nervous system

Classifies diseases of the brain, spinal cord, and peripheral nerves, including epilepsy and neurodegenerative disorders. Used for documenting neurolo...
H00-H59

Diseases of the eye and adnexa

Covers disorders of the eye and its structures, including cataracts, glaucoma, and retinal diseases. Supports ophthalmologic diagnosis and vision-rela...
H60-H95

Diseases of the ear and mastoid process

Includes diseases of the ear and mastoid process such as otitis media, hearing loss, and balance disorders. Used in documenting auditory and vestibula...
I00-I99

Diseases of the circulatory system

Encompasses heart and vascular diseases including hypertension, heart failure, and stroke. Central to cardiovascular care documentation and population...
J00-J99

Diseases of the respiratory system

Covers acute and chronic respiratory conditions such as asthma, COPD, and pneumonia. Supports classification of airway and lung-related diseases....
K00-K95

Diseases of the digestive system

Includes disorders of the digestive organs such as GERD, liver disease, and inflammatory bowel conditions. Used for gastrointestinal diagnosis and pro...
L00-L99

Diseases of the skin and subcutaneous tissue

Classifies diseases of the skin and subcutaneous tissue including dermatitis, psoriasis, and cellulitis. Supports dermatologic care and wound manageme...
M00-M99

Diseases of the musculoskeletal system and connective tissue

Encompasses musculoskeletal and connective tissue disorders such as arthritis and osteoporosis. Used for documenting joint, bone, and soft tissue cond...
N00-N99

Diseases of the genitourinary system

Includes kidney, urinary tract, and non-pregnancy reproductive system disorders. Supports nephrology, urology, and gynecologic condition documentation...
O00-O9A

Pregnancy, childbirth and the puerperium

Covers maternal conditions related to pregnancy, childbirth, and postpartum complications. Used exclusively for documenting obstetric care and materna...
P00-P96

Certain conditions originating in the perinatal period

Includes neonatal conditions originating during pregnancy or birth, such as prematurity and birth trauma. Applied to newborn records for perinatal car...
Q00-QA0

Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders

Classifies congenital malformations, chromosomal abnormalities, and genetic disorders present at birth. Supports pediatric, surgical, and genetic coun...
R00-R99

Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified

Covers symptoms, signs, and abnormal findings without a confirmed diagnosis. Used when clinical evaluation is ongoing or diagnosis remains uncertain....
S00-T88

Injury, poisoning and certain other consequences of external causes

Includes traumatic injuries, poisonings, and complications of medical care. Requires detailed documentation of anatomical site, severity, and encounte...
V00-Y99

External causes of morbidity

Provides external cause codes describing how injuries or conditions occurred. Used alongside injury codes for public health and prevention tracking....
Z00-Z99

Factors influencing health status and contact with health services

Covers encounters for preventive care, screenings, and health status factors such as medical history or device presence. Supports outpatient and routi...
U00-U85

Codes for special purposes

Reserved for special and emerging health conditions requiring rapid classification, such as novel infectious diseases. Supports global standardization...