International or Local Moon Sighting

Q: Should I follow a local or global moon sighting to begin Ramadan?

A: Once the crescent of Ramadan is sighted anywhere and that sighting is established by a valid witness, fasting becomes obligatory upon all Muslims. Local horizons are not considered after a confirmed sighting has been reported.

This is based on the general command of the Prophet ﷺ, “Fast when you see it,” which is addressed to the Ummah as a whole.

The means of conveying that report are not restricted. So long as it traces back to a verified, reliable witness, modern means of communication are acceptable.

What about the hadith of Kurayb?

Kurayb reported that he saw the crescent in Greater Syria on a Friday night, then later informed Ibn ʿAbbās in Madinah. Ibn ʿAbbās replied, “We saw it on Saturday and will continue fasting until we complete thirty days or see it.” When asked whether Muʿāwiyah’s sighting was sufficient, he said, “No. This is how the Messenger of Allah ﷺ commanded us.” (Muslim)

This report does not establish separate moon-sighting zones. Ibn ʿAbbās was speaking about how they would conclude their month, not about dividing the Ummah into regional obligations. The hadith does not address the ruling of the initial day, and many scholars understood it as caution in completing Ramadan rather than proof of independent horizons.

Source: al-Mughni, Sharh al-Muntaha, Kashshaf al-Qinaʿ, Akhṣar al-Mukhtaṣarāt