Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, USA (B).
Southern USA (southern Arizona, southern Texas) and Mexico (including Yucatán Peninsula and islands of Holbox and Cozumel) south to north-western Costa Rica.
 
Population
Estimated population is 2,000,000 (2010).
Northern Beardless Tyrannulet (Camptostoma imberbe) [XC317556]
by Manuel Grosselet from rancho la felicidad cuauthemoc Colima, Colima, Mexico (song)
Northern Beardless Tyrannulet (Camptostoma imberbe) [XC618358]
by Richard E. Webster from San Bernardino National Wildlife Refuge, Cochise County, Arizona, United States (call)
Subspecies
No subspecies.
Forms a superspecies with Southern Beardless Tyrannulet (Camptostoma obsoletum). The two overlap slightly without intergrading in west-central Costa Rica. Birds from southern USA (Arizona) and north-western Mexico, supposedly longer-billed, more olive above and more yellow below, described as subspecies ridgwayi. Birds from Cozumel I, named as thyellophilum on basis of minute differences in mean culmen length in a small sample. However, both considered indistinguishable from other populations.