Sheikh Ahmad Kutty, a senior lecturer and Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states: “The Sunnah is to break the fast as soon as the sun has set; the Prophet (peace and blessings be upon him) always broke his fast as soon as he ascertained the sun had set. He said, “When the sun has departed from here, and the night is creeping from there, that is the time to break the fast.” In other words, the fast should be broken at the time of sunset; there is no mention anywhere in the sources that one must wait until the Adhan has been called or finished calling.
The Prophet’s Sunnah is to hasten to break the fast as soon as the sun has set; to delay breaking the fast is contrary to the Sunnah. In fact we read warnings in the Sunnah against delaying fast breaking: “My Ummah will continue to enjoy goodness so long as they hasten to break their fast without delay (as soon as the sun has set).”
The Sunnah is ta`jil al-fitr (hastening to break the fast immediately after sunset) and not delaying it. To do otherwise is practicing rigidity in religion, which has been condemned by the Prophet (peace and blessings be upon him). So let us recognize that all goodness is in adhering to the Sunnah, the path of moderation.”