Oshkosh Wisconsin ZIP Codes

Oshkosh holds 5 ZIP codes, all inside one county and one postal prefix.

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP.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 Oshkosh codes above are listed without a column we would have to invent.

Scope every ZIP code recorded for Oshkosh. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. ZIP codes are delivery-route groupings, not areas; the boundaries implied by any ZIP map are approximations.

Every Oshkosh ZIP code begins 549. Those first three digits identify the sectional center facility that processes mail for this part of Wisconsin. Statewide that range covers 66 ZIP codes, so Oshkosh accounts for 8% of it.

Every Wisconsin ZIP prefix and the region it covers →

ZIP codes and area codes are separate systems — one routes mail, the other routes calls — and they do not share boundaries. The codes below serve the same ground Oshkosh occupies.

• 274 Area code 274
• 920 Area code 920

Oshkosh Wisconsin area codes in full →

Straight-line distance between place reference points, not driving distance.