ICD-10 Code F31.6 – Bipolar disorder, current episode mixed (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F31.6 – Bipolar disorder, current episode mixed
What it is
Use this code for bipolar disorder when the current episode shows both manic and depressive features at the same time or in close sequence. It indicates a mixed episode, not a single pure manic or depressive state.
Clinical signs
Clinical features may include elevated or irritable mood with increased energy, along with depressive symptoms such as low mood, guilt, or hopelessness. Clinical features vary; refer to documentation.
When to use this code
Assign F31.6 when the provider documents bipolar disorder with a current mixed episode. Use it when the record clearly describes concurrent manic and depressive symptoms, or explicitly states “mixed episode.”
If the note only says bipolar disorder without current episode detail, check documentation. Do not infer mixed features from mood instability alone.
Do not use for
Do not use this code for bipolar disorder in remission, a purely manic episode, or a purely depressive episode. Check documentation if the episode type is not specified.
Coding tip
Code the current episode exactly as documented; mixed features must be supported by the provider’s wording.