CPT Code 99354: Prolonged office service, first hour

When to Use CPT 99354

Use CPT code 99354 when billing for prolonged office service, first hour. This code is used by licensed therapists (LCSW, LPC, MFT, Psychologist) for outpatient sessions.

Adding CPT 99354 to a Superbill

When generating a superbill with CPT 99354, include the ICD-10 diagnosis code, date of service, fee charged, amount paid, and your NPI number. Superbilled pre-fills common therapy CPT codes automatically.

Common ICD-10 Pairings

These diagnosis codes are frequently used alongside CPT 99354:

Documentation Requirements

Document the total face-to-face time, including the E/M time and the additional prolonged time. Explain why the service required time beyond the typical E/M level.

Common Denial Reasons

• ✗ Billed without a qualifying primary E/M service
• ✗ Total time does not meet the threshold for prolonged services
• ✗ Documentation does not justify the extended encounter time

Modifier Notes

Must be billed with a primary E/M code. The first 30 minutes of prolonged time must be completed before billing this code.

Reimbursement Expectations

OON reimbursement typically 45-65% of UCR. Expect $45-$130 for the first prolonged hour.