The 2016 census determined a population of 221 for the state suburb of Northdown.

[1] The name "Northdown" was given to a large house built in the area for Mr. Edward Curr in 1827.

[4] The B74 route (Port Sorell Road) runs through the locality from west to east.

Route C703 (Wrights Lane) starts at an intersection with B74 and runs south before exiting.

Route C707 (Appleby Road) starts at an intersection with B74 and runs south-east before exiting.