[7] 1974–1983: The London Borough of Bromley wards of Biggin Hill, Chelsfield, Darwin, Farnborough, Goddington, Petts Wood, and St Mary Cray.

[8] 1983–1997: In the same borough: Chelsfield and Goddington, Crofton, Farnborough, Orpington Central, Petts Wood and Knoll, and St Mary Cray.

2010–2024: In the same borough: Biggin Hill, Chelsfield and Pratts Bottom, Cray Valley East, Darwin, Farnborough and Crofton, Orpington, and Petts Wood and Knoll.

Further to the 2023 Periodic Review of Westminster constituencies, which came into effect for the 2024 general election, the constituency was defined as comprising the following wards of the London Borough of Bromley as they existed on 1 December 2020: 1.Area marked “4” on the map of the Orpington constituency produced by the Boundary Commission for England[10] The boundary with Bromley and Chislehurst (to be renamed Bromley and Biggin Hill) was realigned with Cray Valley West ward being transferred in (thus uniting the two Cray Valley wards), offset by the loss of Biggin Hill.

It contains the largely buffered settlements of St Mary Cray, parts of St Pauls Cray, Swanley and Ruxley, then ascends through Orpington, Farnborough, and Chelsfield to the uppermost tracts of the North Downs and to the Biggin Hill settlement, which has an airport[16] and retains some of the hill-farming and woodland which dominated the area through the Industrial Revolution until the inter-war period.