zip4lookup

ZIP Codes in Onset, MA

Onset uses 1 ZIP code, all in Plymouth County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.

Free. No account needed.

All 1 Onset ZIP codes

ZIPTypeCountyPopulation
02558 standard Plymouth 1,734

Finding a ZIP+4 in Onset

Knowing which of these 1 ZIP codes covers an address only gets you partway. The four-digit extension identifies the specific delivery point — typically one side of one block. Two houses facing each other on the same Onset street almost always have different ZIP+4 codes even though they share all five leading digits.

Appending ZIP+4 to a mailing list?

Upload a CSV of Onset addresses and download it complete.

Bulk lookup API docs