In April 1705 Charlemont's Regiment left Ireland once more, forming part of an expeditionary force led by the Earl of Peterborough. The force landed in Catalonia in August, and the regiment took part in the Siege of Barcelona, with the city falling in October. In April 1706 the regiment helped relieve Barcelona which was under siege by a Franco-Spanish force. On 10 May 1706 Viscount Charlemont was replaced as colonel by Thomas Allnutt, within the unit becoming Allnutt's Regiment of Foot. Allnutt's Regiment was engaged in a number of minor engagements in Valencia and Murcia throughout the rest of 1706. In April 1707 they became part of a force of English, Portuguese, Dutch and Spanish troops under the command of the Marquis of Minas and Earl of Galway, suffering defeat at the Battle of Almansa. The regiment was nearly destroyed, with Colonel Allnutt wounded and taken prisoner.