Z20 vs Z77

Z20 (Contact with and (suspected) exposure to communicable diseases) compared with Z77 (Other contact with and (suspected) exposures hazardous to health), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).

Can these codes be reported together?

Yes, when both are documented. Z77 carries an Excludes2 note covering Z20: “contact with and (suspected) exposure to communicable diseases (Z20.-)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

Side by side

	Z20Contact with and (suspected) exposure to communicable diseases	Z77Other contact with and (suspected) exposures hazardous to health
Billing status	Non-billable header Report instead: Z20.01, Z20.09, Z20.1, Z20.2, Z20.3	Non-billable header Report instead: Z77.010, Z77.011, Z77.012, Z77.013, Z77.018
Classification	Z00-Z99 — Factors Influencing Health Status and Contact with Health Services (Z00-Z99)	Z00-Z99 — Factors Influencing Health Status and Contact with Health Services (Z00-Z99)
Definition	Contact with and (suspected) exposure to communicable diseases is a non-billable ICD-10-CM category code (Z20).	Other contact with and (suspected) exposures hazardous to health is a non-billable ICD-10-CM category code (Z77).
Includes	—	contact with and (suspected) exposures to potential hazards to health

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Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources