Method and system for avoiding unauthorized wireless communication devices at a femtocell

Methods and systems are provided for reducing a number of unauthorized wireless communication devices (WCDs) on a femtocell. A femtocell may initially provide wireless service on a first femtocell carrier. The femtocell may subsequently receive a registration request from a WCD on the first femtocell carrier. The femtocell may then determine whether the WCD is authorized to receive wireless services from the femtocell. Responsive to making a determination that the WCD is not authorized to receive wireless services, the femtocell may switch to providing service on a second femtocell carrier different than the first.