Under the Fair Labor Standards Act (FLSA), on-call time is considered compensable work time if the employee is "engaged to wait"—meaning their freedom is so heavily restricted that they cannot use the time for their own purposes.
The employee must remain physically on the employer’s premises or very close by.
The employee must respond to calls within a matter of minutes or face severe penalties.
Geographical, activity, or consumption restrictions prevent them from living their life freely (such as not being able to leave the house, run errands, or drink alcohol).
Any time the employee is actually dispatched or actively responding to a call must always be paid.
Conducting meetings to discuss who is on-call and not compensating them is against the law.