248 Area Code: Troy, Michigan

Northern suburban Detroit is served by the 248 area code, with Troy as the primary city in the directory's records. Troy sits in southern Oakland County, on a stretch of the inner Detroit-metro suburbs that has filled in heavily through the postwar decades alongside a substantial concentration of corporate headquarters — many of the world's automotive engineering and supplier firms have offices in the broader Troy/Auburn Hills corridor. The 248 footprint reaches through Pontiac, Bloomfield Hills, Birmingham, Royal Oak, and the broader cluster of Oakland County cities.

In records the directory has compiled for 248 numbers, other Michigan cities — Ann Arbor, Detroit, Flint, and Grand Rapids — recur frequently. None of those are inside the 248 footprint. The pattern reflects standard public-record dynamics, with phone numbers porting across Michigan and addresses linked across multiple cities. The directory currently documents 638 distinct prefixes within 248 in detail, a working subset of the prefix population the code carries.

Troy's median household income runs well above the US figure, in line with the broader Oakland County profile that combines automotive engineering, finance, and a substantial higher-income residential base. Home values come in well above the national median, the city's median age sits noticeably above the US reading at roughly the low forties, and population places Troy as one of the larger suburbs in southeast Michigan. The 248 footprint as a whole reflects a long-running concentration of higher-income suburban communities north of Detroit proper.