Historically, the white-winged duck was widely distributed from northeastern India and Bangladesh, throughout South East Asia to Java and Sumatra. It is now extinct in Java. In India, the duck is found only in the northeastern part of the country, with the main concentration in eastern Assam and adjacent areas of Arunachal Pradesh. However, in 2002 it had a population of only 800, with about 200 in Laos, Thailand, Vietnam and Cambodia, 150 on Sumatra, notably in Way Kambas National Park and 450 in India, Bangladesh and Burma.