She served in defense of the British colonists at Honduras and participated in the repulse of the Spanish expedition at the Battle of St. George's Caye in September 1798. In 1800, after the Spanish threat had passed, she was sold. It is arguable that she deserves the designation "HMS" as Mermaid was never commissioned into the Royal Navy, and her officers and crew were civilians. Even in the case of "His Majesty's hired armed vessels", the Navy provided the captain.