Most of Chinbrook including the main crossroads falls within the London Borough of Lewisham and under the postcode district , although immediately northeast from the crossroads is the border with the London Borough of Bromley and the  postcode district.
Most of Chinbrook, including the main thoroughfare, falls under the jurisdiction of the London Borough of Lewisham and the corresponding postal area. The adjacent area to the north-east, however, is on the border with the London Borough of Bromley and the same postal area.