S5101 HCPCS Code: Day care services (Units, EVV, Rates, Denials)
S5101: Day care services, adult, per half day. Billing unit, which services it covers, modifiers, whether EVV applies, typical rate notes by state and the common denial reasons.
S5101 is “Day care services, adult; per half day.” It is billed per half day and covers a half day of attendance at an adult day center. Medicare does not pay it. EVV does not apply, because the service is delivered at the center, not in the home.
Units and rounding
One unit is one half day. The state’s service definition sets the minimum hours that count as a half day. A full day of attendance is usually billed as one unit of S5102, not two half days.
Modifiers you will see
- U1–U9: State-defined; often distinguish programs (waiver vs state plan), service levels or provider types
- TF / TG: Intermediate or complex level of care, where the state uses levels
Modifier meanings are set by each state and payer, so check your provider manual. See home care billing modifiers.
Typical rates
Adult day rates are set per state program and managed-care plan. Each state program and managed-care plan sets its own rate, so use your state’s current fee schedule.
Common denial reasons
- Attendance shorter than the state’s half-day minimum
- Half day and full day billed for the same date
- Units exceed the authorization
- Service date outside the authorization period
Related codes
Source
CMS HCPCS Level II code set (quarterly update). Confirm the exact descriptor and any state-specific unit definition in your payer’s billing manual. Last reviewed November 6, 2026.
General information, not billing or legal advice. Check your state Medicaid agency’s current fee schedule and provider manual.