Uthman was the youngest member of a six-man delegation of Thaqif representatives sent to establish peace with the Islamic prophet Muhammad on 9 December 630, shortly before the Muslim conquest of their city in 631. The delegation embraced Islam during this meeting, though the 9th-century historians al-Waqidi and Umar ibn Shabba hold Uthman had already converted to Islam during a previous visit to Muhammad in Medina, but had kept it secret from his tribe. Despite his youth, Muhammad declared Uthman governor of Ta'if.
Uthman was a young member of a six-man team sent by the Thaqif people to negotiate peace with Muhammad on December 9, 630, before the Muslim takeover of their city in 631. During this meeting, Uthman and the delegation converted to Islam, although some historians believe he had already made the conversion earlier but kept it secret.