While in the Bahamas, Bonny began mingling with pirates in the local taverns. She met John "Calico Jack" Rackham, captain of the pirate sloop Revenge, and Rackham became her lover. Rackham offered Bonny's husband, James Bonny, money in exchange for her with the purpose of divorcing, but her husband refused.
On August 1720 Anne and Rackham escaped the island together, and Bonny became a member of Rackham's crew. She disguised herself as a man on the ship, and only Rackham and eventually Mary Read were privy to her true sex. When it became clear that Anne was with child, Rackam landed her on the island of Cuba, and there she had a son. Many different theories state that he was left with his family or simply abandoned.
Bonny rejoined Rackham and continued the pirate life, having divorced her husband and married Rackham while at sea. Bonny, Rackham, and Mary Read stole the ship William, then at anchor in Nassau harbour, and put out to sea. Rackham and the two women recruited a new crew. Their crew spent years in Jamaica and the surrounding area. Over the next several months, they enjoyed success, capturing many, albeit smaller, vessels and bringing in abundant treasure.
Bonny took part in combat alongside the men, and the accounts of her exploits present her as competent, effective in combat, and respected by her shipmates. Governor Rogers had named her in a "Wanted Pirates" circular published in the continent's only newspaper, The Boston News-Letter. Although Bonny was historically renowned as a Caribbean pirate, she never commanded a ship of her own.
In October 1720, Rackham and his crew were attacked by a "King's ship", a sloop captained by Jonathan Barnet under a commission from Nicholas Lawes, Governor of Jamaica. Most of Rackham's pirates put up little resistance as many of them were too drunk to fight. However, Read and Bonny fought fiercely and managed to hold off Barnet's troops for a short time. Rackham and his crew were taken to Jamaica, where they were convicted and sentenced by Governor Lawes to be hanged. According to Johnson, Bonny's last words to the imprisoned Rackham were: "Had you fought like a man, you need not have been hang'd like a dog."
After being sentenced, Read and Bonny both "pleaded their bellies," asking for mercy because they were pregnant. In accordance with English common law, both women received a temporary stay of execution until they gave birth. Read died in prison, most likely from a fever from childbirth. Anne stayed in prison until she gave birth and was later released.