Grantham New Hampshire ZIP Codes

Grantham holds a single ZIP code.

Every ZIP code in Grantham

The complete list of Grantham, New Hampshire ZIP codes with the county each falls in.
ZIP code	County
03753	Sullivan County

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP.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

Scope every ZIP code recorded for Grantham. 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.

How these codes cluster

Every Grantham ZIP code begins 037. Those first three digits identify the sectional center facility that processes mail for this part of New Hampshire. Statewide that range covers 29 ZIP codes, so Grantham accounts for 3% of it.

Every New Hampshire ZIP prefix and the region it covers →

Area codes covering Grantham

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

603 Area code 603

Grantham New Hampshire area codes in full →

Where Grantham's ZIP codes sit

Each point is one Grantham ZIP code, plotted from its record coordinates.

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

Cities near Grantham

The closest places to Grantham with their own ZIP code list, nearest first.
City	Distance	ZIP codes
Sunapee New Hampshire ZIP codes	8.7 mi	1 ZIP code
Grafton New Hampshire ZIP codes	9.5 mi	1 ZIP code
Newport New Hampshire ZIP codes	10 mi	1 ZIP code
Lebanon New Hampshire ZIP codes	11 mi	2 ZIP codes
Claremont New Hampshire ZIP codes	13 mi	1 ZIP code
Newbury New Hampshire ZIP codes	14 mi	1 ZIP code
Andover New Hampshire ZIP codes	19 mi	1 ZIP code
Lyme New Hampshire ZIP codes	20 mi	1 ZIP code

Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.