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U.S. ZIP Codes Database 2026

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Belknap County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in Belknap County.

County State ZIP Code City Area Codes
Belknap County NH 03218 Barnstead 603
Belknap County NH 03220 Belmont 603
Belknap County NH 03225 Center Barnstead 603
Belknap County NH 03226 Center Harbor 603
Belknap County NH 03237 Gilmanton 603
Belknap County NH 03246 Laconia 603
Belknap County NH 03247 Laconia 603
Belknap County NH 03249 Gilford 603
Belknap County NH 03252 Lochmere 603
Belknap County NH 03253 Meredith 603
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About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.