A limited number of free birds may be listed for adoption on rescue sites such as RescueMe.org as of 2016. Very few people or rescue agencies list birds for adoption without any fees or restrictions. Bird owners on RescueMe.org may also have their own restrictions and qualifications.
Another site that lists adoptable birds is BestFriends.org, but those birds are not completely free. Adopters may be expected to make donations to bird sanctuaries and prove that they have the means and ability to care for their birds. Local animal shelters often have birds up for adoption for nominal fees after thorough screenings.