unbillable
/ʌnˈbɪləbəl/Definitions
1. adjective
not capable of being billed or charged; unable to be included in an invoice or bill for services or work done.
“The lawyer’s time spent on the pro-bono case was unbillable, as it was a charity case.”
2. noun
an amount or period of time that is not billable.
“The long period of travel time before the actual work project was considered unbillable hours.”