Argentina, Aruba, Bolivia, Brazil, Canada (B), Chile, Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Netherlands Antilles, Nicaragua, Paraguay, Peru, Uruguay (B), USA (B), Venezuela.
Central California and north-western USA southern down both coasts of Mexico, wintering south to northern Central America. Also south-central South America, from south-eastern Bolivia, Paraguay and southern Brazil to north-central Chile, north-central Argentina and Uruguay.
 
Population
Estimated population is 1,200,000 (2010).
White-faced Ibis (Plegadis chihi) [XC698493]
by Robert Dobbs from Mexico City, Federal District, laguna de San Gregorio Atpulco, Mexico (call)
White-faced Ibis (Plegadis chihi) [XC455507]
by Paul Marvin from Pintail Loop, Cameron Prairie NWR, Cameron Parish, LA, United States (call)
Subspecies
Forms superspecies with Glossy Ibis (Plegadis falcinellus), of which formerly considered subspecies. Hybrids have been reported in captivity, but not known under natural conditions in narrow zone of overlap in southern Louisiana, USA.