Rear-Admiral Sir Thomas Louis, 1st Baronet (bap. 11 May 1758 – 17 May 1807) was an officer of the Royal Navy who saw action during the American Revolutionary War and the French Revolutionary Wars. He was one of Horatio Nelson's "Band of Brothers" in the Mediterranean in 1798, commanding a ship at the Battle of the Nile. Later, he was second in command at the Battle of San Domingo, for which service he was made a baronet. Louis died of an unknown ailment aboard his flagship in Alexandria harbour in 1807, and was buried in Malta.