He will join Swindon for training with a view to a move to the County Ground on July 1st, the day after his contract with Bolton expires.
King said: "He played for the reserves at the end of last season and did well, and he is someone I've been after for a little while. He did well when he was on loan at Bury last season and can also play out wide or up front, so could be a good addition for us."