The invention features methods and apparatuses for thermally regulating a laser processing head. A thermal regulation device includes a body shaped to matingly engage a laser processing nozzle and to define a fluid flow boundary of a liquid flow passage between the body and an exterior surface of the laser processing nozzle when the thermal regulation device is affixed to the laser processing nozzle. The thermal regulation device also includes an inlet formed in a first end of the body and configured to provide liquid to the liquid flow passage, the liquid remaining external to an exterior surface of the laser processing nozzle. The thermal regulation device also includes an outlet formed in a second end of the body opposite the first end. The outlet is configured to exhaust liquid from the liquid flow passage.