At what age is Roza farz for a child (girl)? DWQA Questions › Category: ramadhan › At what age is Roza farz for a child (girl)? 0 Vote Up Vote Down JonSnow Staff asked 4 years ago At what age is Roza farz for a child (girl)? 1 Answers 0 Vote Up Vote Down JonSnow Staff answered 4 years ago At her first mense. At last 15years. But girls of 10 years and older should keep all fast.