Sadaqatul fitr is compulsory upon all those who possess wealth that equals the nisaab. Hazrat Abdullah bin Amr (radhiyallahu ‘anhu) reports that Rasulullah (sallallahu ‘alaihi wasallam) sent a person to announce in the streets of Makkah Mukarramah, “Know well that sadaqatul fitr is compulsory upon every Muslim, male or female, free or slave, child or adult, as two mudd of wheat (i.e. half a saa’) or one saa’ from other types of food (e.g. wheat, wheat-flour, dates, etc).” (Sunan Tirmizi #674)