HMS Inflexible was a Bulldog-class sloop designed by Sir William Symonds, Surveyor of the Navy.

Inflexible was the third vessel to carry this name since it was used for an 18-gun sloop, launched by St John's at Lake Champlain on 1 October 1776 and whose fate is unknown.

[4] She was then towed to Devonport and was completed for sea on 9 August 1846 at an initial cost of £50,114[5] including the hull at £22,338, machinery at £18,458 and fitting at £9,418.

[9] By December 1851 she was on the North America and West Indies Station and in June 1852 had joined the Channel Squadron.

She was sold to Castle & Beech in July 1864 then towed from Portsmouth on 8 September 1864 to Charlton for breaking.