CMS-1500 Box 18: Hospitalization dates

What Box 18 is for

Reports related hospitalization from/to dates when applicable to the claim.

What to verify before filing

Compare the entry to the current patient, provider, payer, authorization or service documentation that supports the claim. Avoid copying information from an old claim without confirming that it still applies.

How this field connects to the rest of the claim

CMS-1500 fields work together. A value can be valid by itself but still conflict with the patient, provider, diagnosis, service-line, place-of-service or billing information elsewhere on the claim.

• Box 14 — Date of current illness, injury, or pregnancy
• Box 16 — Dates patient unable to work

Common workflow mistakes

• Using a value from a prior claim without checking the current payer or patient record.
• Assuming a field is always required or always optional for every payer.
• Entering data in a reserved or differently designated field because it appears to have open space.
• Failing to reconcile this field with related service-line, provider or claim-level information.