Montagu Bertie, 5th Earl of Abingdon (30 April 1784 – 16 October 1854), styled Lord Norreys until 1799, was an English peer.
Bertie was the third son of Willoughby Bertie, 4th Earl of Abingdon and Charlotte Warren, a daughter of Peter Warren (Royal Navy officer) and a descendant of the Schuyler family, the Van Cortlandt family, and the Delancey family of British North America. As his two elder brothers predeceased their father, on the latter's death on 26 September 1799 he succeeded him as 5th Earl of Abingdon. His father died insolvent, having sold off much of the estates at Westbury, Wiltshire, but he retained control of the burgages and hence the disposal of the Parliamentary seats for Westbury. The 4th Earl had sold the nomination of members there since 1786 to raise money; his trustees and successor continued the practice until 1810, when he sold the manor and control of the seats to Sir Manasseh Lopes.
Lord Abingdon was awarded a DCL by Oxford University on 3 July 1810. He was Lord Lieutenant of Berkshire between 1826 and 1854 and High Steward of Abingdon. In 1836, he bought the manor of North Weston, now in Great Haseley but then in Thame where he also owned the manor of that name.
Lord Abingdon's first wife was Emily Gage (d. 28 August 1838), daughter of General the Honourable Thomas Gage and Margaret Kemble, 27 August 1807, and a distant cousin with common ancestry to the Schuyler family and Van Cortlandt families of British North America. They lived at Wytham Abbey in Berkshire (now Oxfordshire) and had eight children: