Chapter XVIII of 22
Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
Search within ICD-10-CM — results across the whole code set will include categories R00–R99 from this chapter.
About this chapter
ICD-10-CM Chapter XVIII — “Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified” — spans every category from R00 through R99. Each category in that range expands into a header code and one or more billable codes with additional specificity (laterality, episode of care, or clinical detail). Open any code’s own page to see its exact position in the hierarchy, its parent and children, and whether it’s billable.
This is chapter 18of the 22 chapters in the ICD-10-CM code set. Chapters are arranged by body system or type of condition, and a code’s first letter and two digits (its 3-character category) decide which chapter it falls in: anything from R00 to R99 is filed here.
Related guides
- How ICD-10-CM codes work (and how to read one)
- What does "billable" mean for an ICD-10 code?
- ICD-10 vs CPT vs HCPCS: what's the difference?
All ICD-10-CM chapters
- I. Certain infectious and parasitic diseases (A00–B99)
- II. Neoplasms (C00–D49)
- III. Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50–D89)
- IV. Endocrine, nutritional and metabolic diseases (E00–E89)
- V. Mental, behavioral and neurodevelopmental disorders (F01–F99)
- VI. Diseases of the nervous system (G00–G99)
- VII. Diseases of the eye and adnexa (H00–H59)
- VIII. Diseases of the ear and mastoid process (H60–H95)
- IX. Diseases of the circulatory system (I00–I99)
- X. Diseases of the respiratory system (J00–J99)
- XI. Diseases of the digestive system (K00–K95)
- XII. Diseases of the skin and subcutaneous tissue (L00–L99)
- XIII. Diseases of the musculoskeletal system and connective tissue (M00–M99)
- XIV. Diseases of the genitourinary system (N00–N99)
- XV. Pregnancy, childbirth and the puerperium (O00–O9A)
- XVI. Certain conditions originating in the perinatal period (P00–P96)
- XVII. Congenital malformations, deformations and chromosomal abnormalities (Q00–Q99)
- XVIII. Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00–R99)
- XIX. Injury, poisoning and certain other consequences of external causes (S00–T88)
- XX. External causes of morbidity (V00–Y99)
- XXI. Factors influencing health status and contact with health services (Z00–Z99)
- XXII. Codes for special purposes (U00–U85)