Sleeping though Fajr Prayer
If a person slept through Fajr prayer, will Allaah reward him for the remainder of the prayers on that day, or not? And if he prays it after he wakes up, will it be accepted from him?
It has been authentically reported from the Messenger (sallallaahu alaihi wa sallam) that he said: «» (Al-Bukhari  and Muslim ).
This covers the dawn prayer and others. As for the prayers after it, if he guards them and performs them at the right time, sleeping through Fajr time will not harm him and its reward will be complete according to his actions and his striving in his prayer. But he must not be negligent in this matter, and it is obligatory for him to instruct someone to wake him until he gets up to go to prayer at the right time, or he must place an alarm clock at his head, so that he is not excessive or negligent, and if sleep overcomes him, despite his undertaking precautions, then there is no sin upon him, and he must pray as soon as he wakes up.
Shaykh `Abdul-`Azeez Bin Baz