According to reports, Eid al-Fitr is being celebrated today in Saudi Arabia, the United Arab Emirates, Qatar, and Yemen.
Large congregations for Eid prayers are expected at Masjid al-Haram and Masjid al-Nabawi, with an estimated 2 million worshippers attending.
Meanwhile, Oman, Indonesia, and Brunei will observe Eid on Monday. In the UK, the Muslim community is divided, with some celebrating today and others on Monday.
In the U.S. and Canada, those following a fixed Islamic calendar will celebrate Eid on Sunday, while mosques and organizations that determine the date based on moon sightings will announce their decisions accordingly.