During these voyages she participated as a transport in two military campaigns, the capture of the Cape of Good Hope and of Mauritius.

[1] Euphrates reached Madras on 20 February 1804, was at Vizagapatam on 20 March, and arrived at Calcutta on 7 April.

[5] Then, as Euphrates was coming into London at the end of her voyage, HMS Utile pressed eight of her crew.

[1] Outward bound, she was part of a fleet of transports and East Indiamen carrying some 5000 soldiers under the command of Major-general Sir David Baird to attack the Dutch at the Cape of Good Hope.

A small naval squadron under the orders of Commodore Sir Home Popham escorted the transports.

Homeward bound, Euphrates was at Saugor on 29 December, reached St Helena on 18 April 1807, and arrived at Blackwall on 5 July.

Homeward bound, she was at Saugor on 10 January 1809, reached St Helena on 29 April, and arrived at Blackwall on 17 July.

[1] She left the Cape on 13 June as part of a convoy that also included the East Indiamen Ceylon, Windham, and Astell, and one other.

There the British government hired her as a transport for its forthcoming invasion of Isle de France.

While Northampton, Euprates, and Monarch were in the Channel, they encountered the British frigate HMS Nayaden, which signaled that a flotilla of five French ships of the line that had escaped from Lorient were in the vicinity and that she had exchanged some shots with them.

[1] She left Columbo on 29 December and at 11 p.m. on 1 January 1813 grounded on rocks 100 yards (91 m) off Dondra Head, Ceylon.