Masjid Sultan Mahmud, otherwise known as Masjid Bandar Al-Muktafi Billah Shah, was named after the 16th Sultan of Terengganu. Located in Dungun, it was officiated by the present Sultan of Terengganu, Sultan Mizan Zainal Abidin, in July 2005.
The mosque is a blend of contemporary and Middle Eastern architectural styles. Distinctive sky-blue domes adorn its roof and minarets. Arched pillars line its wraparound verandah and portico, with the arches sporting a colour that matches its domes. Its interior features fine Arabic calligraphies and intricate geometric patterns made with mosaic tiles in different shades of blue.
Religious classes are regularly held in Masjid Sultan Mahmud, which can accommodate up to 1,200 worshippers at a time.