POS 21: Inpatient Hospital
Patient formally admitted as inpatient. Physician E&M billing for inpatient visits.
CMS description
“A facility, other than psychiatric, which primarily provides diagnostic, therapeutic (both surgical and non-surgical), and rehabilitation services by, or under, the supervision of physicians to patients admitted for a variety of medical conditions.”
When to use POS 21
Patient formally admitted as inpatient. Physician E&M billing for inpatient visits.
Reimbursement
Facility rate. Inpatient-specific E&M code families apply (99221-99239).
Common billing issues
- Used when patient is on observation status (should be POS 22)
- Two-midnight rule for inpatient vs observation matters for billing
Frequently asked questions
What is POS 21?
Inpatient Hospital. A facility, other than psychiatric, which primarily provides diagnostic, therapeutic (both surgical and non-surgical), and rehabilitation services by, or under, the supervision of physicians to patients admitted for a variety of medical conditions.
When do I use POS 21?
Patient formally admitted as inpatient. Physician E&M billing for inpatient visits.
How does POS 21 affect reimbursement?
Facility rate. Inpatient-specific E&M code families apply (99221-99239).
What are common POS 21 billing issues?
Used when patient is on observation status (should be POS 22); Two-midnight rule for inpatient vs observation matters for billing.
Related codes
Sources
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