Bellamy did not want to return to his Maria penniless, so changed his career from Treasure Hunter to Pirate. He joined Captain Benjamin Hornigold on his ship "The Marianne" and very successfully "went on the account" throughout the Caribbean.

He was elected Captain over Hornigold and the infamous Blackbeard by the krewe in June of 1716. He made his Pirate's Lair on Bellamy Cay which still exists today. It was formerly known as Blanco Island in Trellis Bay, just north of Tortola in the British Virgin Islands from here, Bellamy could easily prey on heavily laden ships in the Sir Francis Drake Channel.