N.C. Gen. Stat. § 135-48.57

Allowable payments for services provided by a county or city ambulance service shall be paid directly or shall be co-payable to the county or city ambulance service provider. As used in this subsection, "county or city ambulance service" means ambulance services provided by a county or county-franchised ambulance service supplemented by county funds, or a municipally owned and operated ambulance service or by an ambulance service supplemented by municipal funds.