Days One Can’t FastFasting / By askmufti Q: What are the 5 days that you are not permitted to fast? A: One is not allowed to fast on Eidul-Fitr, Eidul-Adh Haa (Bakri Eid) and 3 days after Eidul Adh-Haa. Five days in total. Mufti Siraj Desai