HMS Iris was a 26-gun sixth-rate frigate launched on 14 July 1840 from Devonport Dockyard. She was the first flagship of the Australia Station between 1859 and 1861.
Between 1840 and 15 August 1843, she served with the West Africa Squadron. On 28 April 1841, her boats of war were involved in burning the wharehouses and other property of Niara Bely in Farenya, on the Pongo River.
She was subsequently assigned to the East Indies Station. She was the flagship of the Australian Squadron between 1859 and 1860 under the command of Captain William Loring. She participated in the attack on Puketakauere pā during the First Taranaki War and left the Australia Station in 1861.
Together with HMS Amethyst, HMS Iris was loaned by the Admiralty to the Atlantic Telegraph Company in 1864 and both ships were then extensively modified to be used for ferrying the 1865 Atlantic cable from the manufacturer in Greenwich, London, to the Great Eastern at Sheerness, beginning in February 1865.
Both ships were used for the same purpose in 1866 and 1869 by the Telegraph Construction & Maintenance Company (Telcon). As obsolete sailing vessels which had to be towed while ferrying cable, neither ship was capable of independent operation, and both were described as "hulks" in contemporary reports.
Also in 1866 HMS Iris was loaned to help in the recovery of the steamer Foyle, which sank in collision with the steamer Collingwood off Barking in the Thames on 12 September.
The Sail and Steam Navy List notes that according to Admiralty records, HMS Iris and HMS Amethyst were subsequently sold to Telcon when decommissioned on 16 October 1869.