The constituency was created in 1974, mostly from the former seat of South Buckinghamshire, since which date the area has formed the southernmost part of Buckinghamshire — before 1974 the notable settlements of Slough and Eton, and less well-known Langley, Wraysbury, Sunnymeads and Datchet were in the county. This leads to the unusual shape of the constituency, further accentuated in irregularity by the Thames meander containing Cookham, Berkshire to the west and southwest.
Beaconsfield is estimated to have voted 51% remain in the 2016 referendum on the UK's membership of the EU. Although estimates of the constituency results have not been confirmed, the official UK Electoral Commission EU referendum results detail the area of South Buckinghamshire, which contains the Beaconsfield constituency, as voting to leave the EU with a percentage of 50.7%.
1974–1983: The Urban District of Beaconsfield, the Rural District of Eton, and the parishes of Hedsor and Wooburn in the Rural District of Wycombe. The constituency was formed largely from southern parts of the abolished County Constituency of South Buckinghamshire. The parishes of Hedsor and Wooburn were transferred from the County Constituency of Wycombe. 1983–1997: The District of South Bucks, and the District of Wycombe wards of Bourne End-cum-Hedsor, Flackwell Heath, Loudwater, The Wooburns, and Tylers Green. Gained areas to the east of High Wycombe from Wycombe. The parts of the former Rural District of Eton, including Datchet, which had been transferred from Buckinghamshire to Berkshire by the Local Government Act 1972 were included in the new County Constituency of East Berkshire. 1997–2010: The District of South Bucks, and the District of Wycombe wards of Bourne End-cum-Hedsor, Flackwell Heath, Little Marlow, Loudwater, The Wooburns, and Tylers Green. Minor change. 2010–present: The District of South Bucks, and the District of Wycombe wards of Bourne End-cum-Hedsor, Flackwell Heath and Little Marlow, Marlow North and West, Marlow South East, and The Wooburns. Marlow transferred from Wycombe. The seat consists of Beaconsfield, most of Burnham, Denham, Dorney, Farnham Common, Farnham Royal, Fulmer, Gerrards Cross, Hedgerley, Iver, Stoke Poges, Taplow and Wexham ; Hedsor, Little Marlow, Marlow, Wooburn and Bourne End and the Flackwell Heath settlement of Chepping Wycombe.