ICD-10 Code B36 – Other Superficial Mycoses (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B36 – Other superficial mycoses
What it is
B36 identifies superficial fungal infections that affect the outer layers of skin, hair, or nails and do not fit a more specific mycosis code. Use it when documentation states a nonspecific superficial fungal infection.
Clinical signs
Clinical features vary; refer to documentation. Typical superficial mycoses may present with localized scaling, discoloration, itching, or mild irritation on the skin or nails.
When to use this code
Use B36 when the provider documents “other superficial mycoses,” “superficial fungal infection,” or a similar nonspecific diagnosis without naming a more specific organism or site. It may also apply when the record confirms a superficial mycosis but does not support a more precise code.
Check documentation if the note suggests tinea, candidiasis, or another named fungal disorder, because a more specific code may be required. Code the documented condition, not the suspected one.
Do not use for
Do not use B36 for deep, systemic, or invasive fungal infections. Also avoid it when the record supports a more specific diagnosis such as tinea, candidiasis, or pityriasis versicolor.
Coding tip
If the chart only says “fungal rash,” query for the exact type and site before assigning B36.