Tartar was designed by Sir Thomas Slade and based on Lyme of 1748, "with such alterations as may tend to the better stowing of men and carrying for guns."

The ship was first commissioned in March 1756 under Captain John Lockhart, and earned a reputation as a fast sailer during service in the English Channel.

[1] During the peace that followed, the ship sailed to Barbados carrying a timekeeper built by John Harrison, as a part of a series of experiments used to determine longitude at sea.

On 14 December the French frigate Minerve captured off the island of Ivica the collier Hannibal, which was sailing from Liverpool to Naples.

With HMS Courageux, Meleager, Egmont and Robust, she covered the landing, on 27 August, of 1500 troops sent to remove the republicans occupying the forts guarding the port.