ICD-10 Codes for Adjustment Disorder: F43.20 to F43.29

Match the subtype the clinician documents. "Adjustment disorder with mixed anxiety and depressed mood" is F43.23, one of the most used codes in the group. If the record says only "adjustment disorder", F43.20 is correct; the guidelines ask for the most specific code the documentation supports, and no more specific than that.

Because the stressor is part of the diagnosis, a Z code describing it can be added as a secondary diagnosis, for example Z63.5 for disruption of family by separation and divorce or Z56.0 for unemployment. Social determinant Z codes are secondary only. See the Z code guide.

Several Excludes notes point to or from F43.2. Category F32 (depressive episode) has an Excludes2 note for adjustment disorder (F43.2), and category F41 (other anxiety disorders) has one for transient adjustment reaction (F43.2). Excludes2 means the conditions are separate and both may be coded when both are documented.

Grief needs care. "Grief reaction" is an inclusion term under F43.2, while F43.81 is prolonged grief disorder, with inclusion terms complicated grief and persistent complex bereavement disorder. The clinician's documented diagnosis decides which applies.

Not every reaction to a hard event is a disorder. When the clinician judges that a client's distress does not amount to a diagnosable condition, the record may describe the problem with a Z code instead, such as Z73.3, Stress, not elsewhere classified, or a social determinant code like Z56.0 for unemployment. That choice belongs to the clinician and should be explained in the assessment.

Keep the claim rules in mind. Social determinant codes (Z55 to Z65) are reported as secondary diagnoses only under the FY2027 guidelines, and many payers do not cover psychotherapy when the only diagnosis is a Z code. If an adjustment disorder is diagnosed, F43.2x goes first and the stressor Z code, when used, follows it.

Because the diagnosis is defined by a stressor and the reaction to it, the strongest notes keep both in view. Name the stressor early in treatment, then track how the client is coping with it and how symptoms change. If the stressor resolves or the picture changes, the clinician may revise the diagnosis, and the code on the claim should follow.

Example assessment line for a DAP note: "Adjustment disorder with mixed anxiety and depressed mood (F43.23) following job loss in August. Reports sleeping 6 hours, up from 4; applied to three positions this week. Worry about finances remains high." The note names the stressor, the subtype, and measurable change.

When a client reports a new, unrelated problem, document it separately rather than folding it into the adjustment disorder. If it becomes a second treated diagnosis, it needs its own code and its own documentation.

Most adjustment disorder treatment is individual psychotherapy, billed by time with 90832, 90834 or 90837. The diagnosis is usually established at a 90791 diagnostic evaluation. Some payers limit the number of covered sessions for adjustment disorders, so check benefits and keep progress documented.