Loudon County ZIP Codes

Loudon County is a county of Tennessee.

ZIP codes: 5
Cities & towns: 4
Area codes: 3
Land area: 229 sq mi

Every ZIP code in Loudon County

377xx–378xx

The complete list of Loudon County, TN ZIP codes with the city each one delivers to.
ZIP code	City
37742	Greenback
37771	Lenoir City
37772	Lenoir City
37774	Loudon
37846	Philadelphia

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP. USPS delivery-type products are licensed, and no clean-rights source maps ZIP codes to neighbourhoods — so the Loudon County codes above are listed without a column we would have to invent.

Cities and towns in Loudon County

Area codes covering Loudon County

Telephone and postal boundaries are drawn by different bodies, so these codes overlap the county without matching its edges.

Where Loudon County's ZIP codes sit

Each point is the reference point of one Loudon County ZIP code, plotted from its record coordinates. The outline is the convex envelope of those points — a footprint, not a boundary.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Scope every ZIP code recorded in Loudon County. Source GeoNames US postal codes (2026-07 postal dump), Census 2024 county Gazetteer (2024 Gazetteer) and geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot). Updated 16 July 2026. The outline is a convex envelope of ZIP reference points, not a jurisdiction boundary.