The Hired tender Louisa served the British Royal Navy from 24 April 1803 to 1809. She was of 120 tons (bm) and was armed with three or four 3-pounder guns and six ½-pounder swivel guns.
On 28 October 1807 Louisa, under the command of Lieutenant Hoy, engaged with a privateer of 14 guns. Hoy received promotion to Commander for this action. The Admiralty also thanked Lieutenant Herbert Brace Powell for his part in the action. Later reports do state that the privateer was the Marsouin. Unfortunately, there is no readily accessible record of what transpired, and what Lieutenant Powell's role was. Still, in 1847 the Admiralty authorized the issue of the Naval General Service Medal with clasp "Louisa 28 Octr. 1807" to all surviving claimants from the action, of which there was one.
Shortly thereafter, on 24 January 1808, the frigate Iris captured the French privateer lugger Marsouin. of 14 guns and 60 men; she had thrown her guns and anchors overboard during the chase. Captain John Tower, of Iris reported that an examination of her logs and muster list revealed that on her last cruise on 28 October, near Cork, she had attempted to board a transport. The concealed troops fired a small arms volley that killed Marsouin's captain and ten men, and wounded five others.
In 1808 Louisa was on the Irish station and under the command of Lieutenant John Page.