What is the ruling on sleeping while fasting, whether the fasting is obligatory or voluntary? Does it affect the reward of fasting?

All perfect praise be to Allaah, the Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

There is no harm if the fasting person sleeps during the daytime, whether it is obligatory or voluntary fasting. However, it is disliked for the fasting person to sleep much because this makes him miss performing many acts of worship.

This ruling was stated by some Islamic jurists including Al-Kharashi Al-Maaliki, May Allaah have mercy upon him, who listed it under the disliked acts of fasting. He also reported that this was the opinion of ‘Iyaadh and Ibn Juzi .

Allaah Knows best.