Last name Ngay (Ngay 
, Ngày ) , globally, is quite a rare family name. The family name Ngay is characteristic of South-eastern Asia, particularly Vietnam, where it is quite a rare surname, Myanmar, where it is a rare surname, and Singapore. Measured by absolute frequency, this name is the most popular in South-eastern Asia, particularly Vietnam, Myanmar, and Philippines. Very seldom, Ngay is the forename as well as the last name.