03857 ZIP Code — Newmarket, NH
Rockingham County, New Hampshire
ZIP code 03857 is located in Newmarket, New Hampshire, within Rockingham County. It covers approximately 12.59 square miles and serves a population of 9,400 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 603.
About ZIP code 03857
The housing stock consists of a significant share of large multi-unit buildings. Most homes were built in the 1980s, giving the area an established character. Median home value is $369,900. Owner-occupancy sits near the national average at 54%.
Median household income is $98,002. The poverty rate of 4% is below the national average.
The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 29 minutes is near the national average.
Educational attainment is high — 50% of residents hold a bachelor's degree or higher, well above the national average of 33%.
9,400
population
12.59
sq mi land
Standard
ZIP type
Eastern (ET)
timezone
03857 ZIP code map
Cities in ZIP code 03857
Below are the cities the US Postal Service accepts for ZIP code 03857. Using any city not on this list may result in mail delivery delays.
| City | Status |
|---|---|
| Newmarket | Preferred |
Nearby ZIP codes
03856 Newfields (2.3 mi)
03824 Durham (4 mi)
03885 Stratham (4.6 mi)
03840 Greenland (5.7 mi)
03042 Epping (6.6 mi)
03833 Exeter (7.6 mi)
03801 Portsmouth (7.7 mi)
03820 Dover (8.7 mi)
03862 North Hampton (8.7 mi)
03290 Nottingham (9.4 mi)
03803 Portsmouth (9.5 mi)
03822 Dover (9.7 mi)
Demographics
updated 05/2026
| Population | |
|---|---|
| Total population | 9,400 |
| Population density | 747 / sq mi |
| State FIPS | 33 |
| County FIPS | 015 |
| Geography | |
|---|---|
| Land area | 12.59 sq mi |
| Water area | 1.60 sq mi |
| Latitude | 43.0689 |
| Longitude | -70.9519 |
| Timezone | Eastern (ET) |
| Area code | 603 |
Total population by age
Gender
Race & ethnicity
Economics
updated 05/2026
Household income
| Income range | This ZIP | County avg | State avg |
|---|---|---|---|
| Under $50k | 30.4% | 23.5% | 31.0% |
| $50k – $100k | 33.1% | 29.1% | 31.2% |
| $100k – $200k | 27.9% | 32.8% | 28.1% |
| Over $200k | 8.6% | 14.6% | 9.7% |
Demographics & statistics
9,400
Population
747
People per sq mi
38.5
Median age
$98,002
Median household income
$51,411
Per capita income
$369,900
Median home value
$1,573
Median monthly rent
54.3%
Home ownership
4.0%
Poverty rate
1.5%
Unemployment
2,429
Housing units
49.6%
Bachelor's or higher
Age distribution
Male
Female
232
Under 5
212
213
5–9
194
267
10–14
242
170
15–19
154
376
20–24
342
954
25–34
868
705
35–44
641
627
45–54
571
180
55–59
163
401
60–64
364
502
65–74
457
259
75–84
236
37
85+
33
← Male
Female →
Age summary
| Group | Count | % |
|---|---|---|
| Under 18 | 1,575 | 16.8% |
| 18 and over | 7,825 | 83.2% |
| 65 and over | 1,524 | 16.2% |
| Median age | 38.5 years | |
Race & ethnicity
White
91.9%
Two or more races
3.8%
Asian
1.4%
Hispanic or Latino
1.3%
Black or African American
0.9%
Other race
0.7%
| Group | Count | % |
|---|---|---|
| White | 8,754 | 91.9% |
| Two or more races | 363 | 3.8% |
| Asian | 130 | 1.4% |
| Hispanic or Latino | 123 | 1.3% |
| Black or African American | 90 | 0.9% |
| Other race | 63 | 0.7% |
Household income
| Income range | This ZIP | County avg | State avg |
|---|---|---|---|
| Under $50k | 30.4% | 23.5% | 31.0% |
| $50k – $100k | 33.1% | 29.1% | 31.2% |
| $100k – $200k | 27.9% | 32.8% | 28.1% |
| Over $200k | 8.6% | 14.6% | 9.7% |
Under $10k
2.3%
$15k–$25k
5.6%
$25k–$35k
5.2%
$35k–$50k
8.6%
$50k–$75k
15.3%
$75k–$100k
15.6%
$100k–$150k
23.6%
$150k–$200k
13.9%
$200k+
9.9%
| Range | % of households |
|---|---|
| Under $10k | 2.3% |
| $15k–$25k | 5.6% |
| $25k–$35k | 5.2% |
| $35k–$50k | 8.6% |
| $50k–$75k | 15.3% |
| $75k–$100k | 15.6% |
| $100k–$150k | 23.6% |
| $150k–$200k | 13.9% |
| $200k+ | 9.9% |
| Median income | $98,002 |
Housing
Home values
Under $50k
0.2%
$50k–$100k
0.9%
$100k–$150k
0.7%
$150k–$200k
4.8%
$200k–$300k
16.1%
$300k–$500k
59.4%
$500k–$1M
17.8%
Housing overview
| Metric | Value |
|---|---|
| Median home value | $369,900 |
| Median rent / month | $1,573 |
| Owner occupied | 54.3% |
| Renter occupied | 45.7% |
| Vacant | 3.4% |
| Single-family detached | 43.6% |
| Large apartment buildings | 20.2% |
| Mobile homes | 2.6% |
| Median rooms | 5.3 |
| Avg household size (owned) | 2.57 |
Year built
| Era | % |
|---|---|
| 2020 or later | 0.2% |
| 2010–2019 | 4.1% |
| 2000–2009 | 12.5% |
| 1990–1999 | 14.1% |
| 1980–1989 | 26.4% |
| 1970–1979 | 12.4% |
| 1960–1969 | 3.6% |
| 1950–1959 | 6.5% |
| 1940–1949 | 0.8% |
| 1939 or earlier | 19.4% |
Bedrooms
| Size | % of units |
|---|---|
| No bedroom (studio) | 0.6% |
| 1 bedroom | 11.6% |
| 2 bedrooms | 42.9% |
| 3 bedrooms | 34.5% |
| 4 bedrooms | 9.3% |
| 5+ bedrooms | 1.0% |
Vehicles per household
| Vehicles | % of households |
|---|---|
| No vehicle | 1.1% |
| 1 vehicle | 33.4% |
| 2 vehicles | 51.0% |
| 3 or more | 14.5% |
Heating fuel
| Fuel type | % |
|---|---|
| Utility gas | 5.9% |
| Electricity | 26.3% |
| Propane / LP gas | 21.8% |
| Fuel oil | 41.7% |
| Wood | 2.5% |
| Solar | 0.2% |
| No fuel used | 0.6% |
Households & families
| Household type | Count | % |
|---|---|---|
| Married-couple family | 1,861 | 44.3% |
| Cohabiting couple | 611 | 14.5% |
| Male householder, no spouse | 817 | 19.4% |
| Female householder, no spouse | 914 | 21.7% |
| Households with children under 18 | 1,001 | 23.8% |
| Households with seniors (65+) | 1,046 | 24.9% |
| Average household size | 2.23 | |
Marital status
| Status | Male | Female |
|---|---|---|
| Never married | 41.1% | 29.8% |
| Married | 48.2% | 50.8% |
| Separated | 0.8% | 0.0% |
| Widowed | 1.6% | 6.0% |
| Divorced | 8.3% | 13.4% |
Education
Less than 9th grade
0.2%
Some HS, no diploma
1.4%
HS graduate
16.1%
Some college, no degree
20.3%
Associate's degree
12.4%
Bachelor's degree
32.6%
Graduate / professional
17.0%
| Metric | % |
|---|---|
| HS diploma or higher | 98.4% |
| Bachelor's or higher | 49.6% |
School enrollment (ages 3–17)
| Type | Count | % |
|---|---|---|
| Nursery / preschool | 160 | 8.7% |
| Kindergarten | 96 | 5.2% |
| Elementary school | 670 | 36.3% |
| High school | 350 | 19.0% |
| College / grad school | 569 | 30.8% |
Employment
Industry of employment
Education & healthcare
29.9%
Professional & management
12.7%
Manufacturing
12.5%
Arts, food & hospitality
10.7%
Retail trade
9.7%
Finance & real estate
6.9%
Transportation & utilities
3.5%
Other services
3.5%
Construction
3.2%
Wholesale trade
2.9%
Public administration
2.6%
Agriculture & mining
1.3%
Information
0.5%
Occupation
| Category | % |
|---|---|
| Management, business & arts | 53.4% |
| Service | 13.5% |
| Sales & office | 20.4% |
| Natural resources & construction | 4.6% |
| Production & transportation | 8.1% |
Employment type
| Type | % |
|---|---|
| Private sector | 81.3% |
| Government | 13.2% |
| Self-employed | 5.5% |
| Unpaid family workers | 0.0% |
Commute
| Method | % |
|---|---|
| Drive alone | 76.6% |
| Carpool | 6.3% |
| Public transit | 1.0% |
| Walk | 3.3% |
| Work from home | 12.7% |
| Other means | 0.2% |
| Avg commute (minutes) | 28.7 |
Poverty
All people
4.0%
Under 18 years
0.0%
18 and over
4.8%
Married-couple families
0.0%
Female-led households
0.0%
Income support
| Source | % of households |
|---|---|
| Social Security | 27.1% |
| Retirement income | 20.9% |
| Supplemental Security | 2.9% |
| Cash public assistance | 1.0% |
| Food stamps / SNAP | 4.3% |
Health indicators
| Condition | % |
|---|---|
| Obesity | 28.4% |
| High blood pressure | 25.7% |
| High cholesterol | 27.9% |
| Diabetes | 6.5% |
| Heart disease | 4.1% |
| Stroke | 1.9% |
| Asthma | 9.9% |
| Arthritis | 19.1% |
| Kidney disease | 2.0% |
| Pulmonary disease | 4.6% |
| Cancer | 5.5% |
| Behavior / access | % |
|---|---|
| Smoking | 13.7% |
| Binge drinking | 20.2% |
| No physical activity | 15.3% |
| Less than 7 hrs sleep | 29.5% |
| Depression | 20.3% |
| Fair or poor health | 9.2% |
| Poor mental health | 14.5% |
| Poor physical health | 8.1% |
| No health insurance | 8.8% |
| Visited doctor (checkup) | 70.7% |
| Visited dentist | 73.7% |
| Cholesterol screening | 89.3% |
| Teeth loss | 9.3% |
Veterans & disability
| Veterans | Count | % |
|---|---|---|
| Civilian veterans | 656 | 8.5% |
| Disability | % |
|---|---|
| Any disability | 8.2% |
| Under 18 | 2.0% |
| 18–64 years | 6.0% |
| 65 and over | 23.7% |
Health insurance coverage
| Type | % |
|---|---|
| Private insurance | 82.3% |
| Public insurance | 23.6% |
| No insurance | 4.6% |
| Uninsured under 19 | 0.0% |
Language & origin
Language spoken at home (age 5+)
| Language | Count | % |
|---|---|---|
| English only | 8,956 | 95.3% |
| Spanish | 86 | 1.0% |
| Other Indo-European | 38 | 0.4% |
| Asian & Pacific Islander | 48 | 0.5% |
| Other languages | 0 | 0.0% |
Place of birth & citizenship
| Origin | Count | % |
|---|---|---|
| Native born (US) | 9,143 | 97.3% |
| Born in same state | 9,040 | 96.2% |
| Born in different state | 3,532 | 37.6% |
| Foreign born | 103 | 1.1% |
| Naturalized citizen | 257 | 2.7% |
| Not a US citizen | 119 | 46.3% |
Ancestry
| Ancestry | Count | % |
|---|---|---|
| French | 1,700 | 18.1% |
| Italian | 1,561 | 16.6% |
| German | 890 | 9.5% |
| Arab | 514 | 5.5% |
| English | 127 | 1.4% |
| Ancestry | Count | % |
|---|---|---|
| Polish | 71 | 0.8% |
| Dutch | 25 | 0.3% |
| Irish | 24 | 0.3% |
| Norwegian | 20 | 0.2% |
Technology access
| Metric | % of households |
|---|---|
| Computer access | 44.7% |
| Internet access | 98.8% |
Source: U.S. Census Bureau, American Community Survey 2025 estimates.
Frequently asked questions about ZIP code 03857
What city is ZIP code 03857 in?
ZIP code 03857 is primarily assigned to Newmarket, New Hampshire.
What county is ZIP code 03857 in?
ZIP code 03857 falls within Rockingham County, New Hampshire.
How educated is the population of ZIP code 03857?
50% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.
What is the typical home value in ZIP code 03857?
The median home value in ZIP code 03857 is $369,900.
What is the population of ZIP code 03857?
ZIP code 03857 has an estimated population of 9,400 residents, with a density of 746 people per square mile.
What is the median household income in ZIP code 03857?
The median household income in ZIP code 03857 is $98,002, above the national median of ~$75,000.
What timezone is ZIP code 03857 in?
ZIP code 03857 observes the EST timezone.