Residential delivery area · New Hampshire
ZIP Code 03237: Gilmanton, NH
ZIP code 03237 uses the postal name Gilmanton, New Hampshire and lies entirely in Belknap County (Census 2020 ZIP-county file). About 2,600 people live there (Census Bureau, ACS 2020-2024). Median household income is $111,359 (Census Bureau, ACS 2020-2024). Its land lies outside any incorporated or census-designated place.
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Gilmanton · its only residential ZIP
- County
- Belknap County
- Micro area
- Laconia, NH
- House district
- NH-1 119th Congress
- State
- New Hampshire
- Time zone
- Eastern
- Land area
- 38.0 sq mi · 68 people per sq mi
Where is ZIP code 03237?
03237 centers on 43.432°, -71.388° and covers 38.0 square miles of land plus 1.0 of water. It borders 8 ZIP codes: 03837, 03220, 03249, 03810, 03307, 03218, 03224, 03263.
The map draws ZIP code areas only. For the streets inside 03237, open its center on OpenStreetMap.
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries and the 2023 Gazetteer (2020 ZCTAs); ZIP-to-county shares, Census places and House districts (119th Congress) from the Census 2020 relationship files (shares of land); metro area from the OMB delineation (July 2023); town name and time zone from simplemaps US ZIP Codes (CC BY 4.0).
How does 03237 compare with the rest of Belknap County?
| Measure | 03237 | In Belknap County | In NH |
|---|---|---|---|
| People (ACS 2020-2024) | 2,575 | 9th of 14 | 128th of 247 |
| Median household income | $111k | 4th of 9 | 52nd of 158 |
| Median home value | $345k | 11th of 14 | 123rd of 191 |
Its median household income is higher than in 87% of U.S. residential ZIP codes, and it is denser than 47% of all U.S. residential ZIP codes. ZIP codes at the ACS caps ($250,000 or more for household income, $2,000,000 or more for home value) share the top rank.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B19013, B25077); ranks by PlainZIP over residential ZIP codes (ZCTAs).
How many people live in 03237?
The 2020 Census counted 2,478 people in 03237; the ACS, which samples households over 2020-2024, estimates 2,575. Between the 2010 and 2020 censuses its population grew 9.9% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 2,575±456 (90% margin)
- 2020 Census count
- 2,478+9.9% since 2010 (2,254)
- Households
- 1,097
- Median age
- 43.2
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B01002, B11001); 2020 Census (DHC P1); 2010 Census (SF1 P1).
Who lives in 03237?
Of the 2,575 people the ACS estimates in 03237, 16.8% are under 18 and 14.8% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (93.7%).
- Under 1816.8%
- 18 to 6468.5%
- 65 and older14.8%
- White, not Hispanic93.7%
- Other or two or more3.8%
- Hispanic or Latino2.4%
- Black, not Hispanic0.0%
- Asian, not Hispanic0.0%
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01001 age by sex, B03002 Hispanic or Latino origin by race); shares of the estimated population, small ZIP codes carry wide margins.
What do households in 03237 earn?
Median household income is $111,359 (ACS 2020-2024), the 4th highest of the 9 ranked ZIP codes in Belknap County. It rose from $93,803 in 2015-2019 (in 2024 dollars), a change larger than the surveys' margins of error.
- Median household income
- $111,359±$14,336
- Income per person
- $52,479
- Below the poverty line
- 5.4%
- Unemployed (of the labor force)
- 7.4%
- Adults 25+ with a bachelor's degree
- 36.1%
- Adjusted gross income per tax return, 2022
- $90,2231,390 returns; wages 67% of AGI (IRS)
Source: U.S. Census Bureau, ACS 2020-2024 and 2015-2019 5-year estimates (B19013, B19301, B17001, B23025, B15003; 2015-2019 dollars converted with the BLS CPI-U, 1.22699); IRS Statistics of Income, ZIP code data, tax year 2022 (adjusted gross income per return, filed under the address on the return).
What are homes worth in 03237?
FHFA's house price index for 03237, built from repeat sales and appraisals of the same homes, rose 121% from 2015 to 2025 and rose 67% from 2020 to 2025, and moved +5.8% in 2025.
- Median home value (owners' estimate)
- $345,400
- Median gross rent
- –
- Homes owned by their occupants
- 98.9%
- Housing units
- 1,390
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B25077, B25064, B25003, B25001); FHFA House Price Index, annual five-digit ZIP, updated 2026-03-31.
What businesses are in 03237?
40 business establishments had a location in this ZIP code in 2023, 14 more than in 2018; the most are in construction (ZIP Code Business Patterns).
- Construction17
- Administrative and support and waste management and remediation services6
- Retail trade3
- Real estate and rental and leasing3
Source: U.S. Census Bureau, ZIP Code Business Patterns 2023 and 2018 (establishments with paid employees, by the business's ZIP code).
Which ZIP codes are next to 03237?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 03837 | Gilmanton Iron Works | 1,451 | $120k | 2.7 mi |
| 03220 | Belmont | 7,393 | $68k | 5.6 mi |
| 03249 | Gilford | 7,830 | $117k | 6.1 mi |
| 03810 | Alton Bay | 2,314 | $148k | 7.3 mi |
| 03307 | Loudon | 5,724 | $107k | 7.4 mi |
| 03218 | Barnstead | 1,160 | $113k | 8.7 mi |
| 03224 | Canterbury | 2,392 | $138k | 9.8 mi |
| 03263 | Pittsfield | 4,105 | $74k | 10.6 mi |
| 03225 | Center Barnstead | 3,834 | $112k | 8.7 mi (near) |
| 03276 | Tilton | 9,015 | $82k | 9.5 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.