Sydenham is home to working-age Londoners in their thirties and forties, split almost evenly between owners and renters. Under half own. The typical resident is under 40. Half hold a degree. Students barely register.
At the 2021 census, which is the source for every population figure on this page, about 47% of Sydenham's households owned their home, 22% rented privately and 30% rented from the council or a housing association. Social landlords house more of Sydenham than private ones do, which is the reverse of what the period villas on the hill lead people to expect.
The median resident is 38, and about 34% of people are between 25 and 44. Sydenham is a district of people who have stopped sharing flats and started arguing about nursery places.
The Office for National Statistics models average household income across Sydenham at about £75,800 before tax for the financial year to March 2023. That is a gross household figure, often from two earners, and a few years old now.
About 31% of households are one person living alone, and about 9% are a single pensioner, a group already counted inside that 31%. Couples with dependent children make up about 17% of households, and lone parents another 17%, so a family on a Sydenham street is as likely to have one adult at the school gate as two.
About 52% of residents aged 16 and over hold a degree or equivalent, about 14% have no formal qualifications and only about 2% are full-time students. Sydenham has no college of its own, and its sixth-formers leave for university and mostly come back older, with a mortgage application.
About 85% of residents described their health as good or very good in 2021. Across Lewisham as a whole, the rate of deaths from preventable causes is similar to the England average, and so is the smoking rate, at about 9% of adults.
Sydenham is a middling neighbourhood by the usual measures, mixed in income and housing, with a well-qualified working-age core living alongside a large social-rented population, and no single type of resident sets the tone.