04421 ZIP Code — Castine, ME

Hancock County, Maine

ZIP code 04421 is located in Castine, Maine, within Hancock County. It covers approximately 7.78 square miles and serves a population of 1,289 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 207.

About ZIP code 04421

The housing stock consists of predominantly single-family detached homes. Most homes were built in the pre-1940, giving the area an established character. Median home value is $413,300. Owner-occupancy is high at 77%, well above the national average.

Median household income is $78,088. 40% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 14 minutes is near the national average.

Educational attainment is high — 64% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 04421 reflects a community defined by a highly educated population, high homeownership, and a significant Social Security-dependent population.

1,289

population

7.78

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

04421 ZIP code map

Cities in ZIP code 04421

Below are the cities the US Postal Service accepts for ZIP code 04421. Using any city not on this list may result in mail delivery delays.

City	Status
Castine	Preferred

Nearby ZIP codes

04420 Castine (1.9 mi) 04617 Brooksville (4.3 mi) 04476 Penobscot (6.2 mi) 04981 Stockton Springs (8.5 mi) 04676 Sedgwick (8.8 mi) 04974 Searsport (8.8 mi) 04848 Islesboro (9.3 mi) 04650 Little Deer Isle (9.4 mi) 04614 Blue Hill (10.2 mi) 04472 Orland (12.7 mi) 04616 Brooklin (13.4 mi) 04915 Belfast (13.5 mi)

Demographics updated 05/2026

Population
Total population	1,289
Population density	166 / sq mi
State FIPS	23
County FIPS	009

Geography
Land area	7.78 sq mi
Water area	12.23 sq mi
Latitude	44.4149
Longitude	-68.7935
Timezone	Eastern (ET)
Area code	207

Total population by age

Gender

Race & ethnicity

Economics updated 05/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	43.2%	42.0%	42.3%
$50k – $100k	23.4%	34.2%	32.3%
$100k – $200k	24.0%	18.8%	20.6%
Over $200k	9.4%	5.0%	4.9%

Demographics & statistics

1,289

Population

166

People per sq mi

20.8

Median age

$78,088

Median household income

$29,062

Per capita income

$413,300

Median home value

$992

Median monthly rent

77.2%

Home ownership

15.3%

Poverty rate

3.4%

Unemployment

649

Housing units

64.2%

Bachelor's or higher

Age distribution

Male Female

Under 5

5–9

10–14

235

15–19

143

178

20–24

108

25–34

35–44

45–54

55–59

60–64

65–74

75–84

85+

← Male

Female →

Age summary

Group	Count	%
Under 18	134	10.4%
18 and over	1,155	89.6%
65 and over	220	17.1%
Median age	20.8 years

Race & ethnicity

White 86.9%

Two or more races 7.6%

Hispanic or Latino 3.4%

Black or African American 1.8%

Asian 0.1%

Other race 0.1%

Group	Count	%
White	1,160	86.9%
Two or more races	102	7.6%
Hispanic or Latino	46	3.4%
Black or African American	24	1.8%
Asian	2	0.1%
Other race	1	0.1%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	43.2%	42.0%	42.3%
$50k – $100k	23.4%	34.2%	32.3%
$100k – $200k	24.0%	18.8%	20.6%
Over $200k	9.4%	5.0%	4.9%

Under $10k 14.2%

$15k–$25k 0.3%

$25k–$35k 6.0%

$35k–$50k 7.3%

$50k–$75k 18.4%

$75k–$100k 11.4%

$100k–$150k 9.5%

$150k–$200k 20.9%

$200k+ 12.0%

Range	% of households
Under $10k	14.2%
$15k–$25k	0.3%
$25k–$35k	6.0%
$35k–$50k	7.3%
$50k–$75k	18.4%
$75k–$100k	11.4%
$100k–$150k	9.5%
$150k–$200k	20.9%
$200k+	12.0%
Median income	$78,088

Housing

Home values

Under $50k 2.5%

$100k–$150k 3.3%

$150k–$200k 4.1%

$200k–$300k 9.0%

$300k–$500k 36.5%

$500k–$1M 38.5%

$1M+ 6.1%

Housing overview

Metric	Value
Median home value	$413,300
Median rent / month	$992
Owner occupied	77.2%
Renter occupied	22.8%
Vacant	56.2%
Single-family detached	92.6%
Large apartment buildings	0.0%
Mobile homes	3.7%
Median rooms	6.5
Avg household size (owned)	2.24

Year built

Era	%
2020 or later	0.0%
2010–2019	0.8%
2000–2009	13.6%
1990–1999	11.0%
1980–1989	14.1%
1970–1979	11.4%
1960–1969	3.6%
1950–1959	5.1%
1940–1949	3.7%
1939 or earlier	36.6%

Bedrooms

Size	% of units
No bedroom (studio)	6.9%
1 bedroom	4.3%
2 bedrooms	19.3%
3 bedrooms	35.0%
4 bedrooms	21.8%
5+ bedrooms	12.8%

Vehicles per household

Vehicles	% of households
No vehicle	13.3%
1 vehicle	19.0%
2 vehicles	46.2%
3 or more	21.5%

Heating fuel

Fuel type	%
Electricity	3.2%
Propane / LP gas	16.1%
Fuel oil	71.5%
Wood	8.2%

Households & families

Household type	Count	%
Married-couple family	173	54.7%
Cohabiting couple	10	3.2%
Male householder, no spouse	51	16.1%
Female householder, no spouse	82	25.9%
Households with children under 18	86	27.2%
Households with seniors (65+)	144	45.6%
Average household size	2.24

Marital status

Status	Male	Female
Never married	70.2%	35.3%
Married	25.9%	40.3%
Separated	0.0%	7.4%
Widowed	0.4%	3.5%
Divorced	3.5%	13.6%

Education

Less than 9th grade 1.3%

Some HS, no diploma 0.4%

HS graduate 9.4%

Some college, no degree 13.9%

Associate's degree 10.7%

Bachelor's degree 27.1%

Graduate / professional 37.1%

Metric	%
HS diploma or higher	98.3%
Bachelor's or higher	64.2%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	0	0.0%
Kindergarten	0	0.0%
Elementary school	75	9.6%
High school	52	6.7%
College / grad school	654	83.7%

Employment

Industry of employment

Education & healthcare 43.8%

Arts, food & hospitality 17.4%

Retail trade 8.5%

Manufacturing 7.9%

Finance & real estate 7.2%

Construction 5.3%

Other services 2.6%

Transportation & utilities 2.3%

Agriculture & mining 1.8%

Public administration 1.8%

Professional & management 1.4%

Occupation

Category	%
Management, business & arts	43.8%
Service	21.5%
Sales & office	20.1%
Natural resources & construction	4.8%
Production & transportation	9.9%

Employment type

Type	%
Private sector	81.5%
Government	16.2%
Self-employed	2.3%
Unpaid family workers	0.0%

Commute

Method	%
Drive alone	35.0%
Carpool	4.4%
Public transit	0.0%
Walk	41.2%
Work from home	15.1%
Other means	4.2%
Avg commute (minutes)	14.3

Poverty

All people 15.3%

Under 18 years 26.9%

18 and over 12.6%

Married-couple families 1.2%

Female-led households 53.6%

Income support

Source	% of households
Social Security	39.6%
Retirement income	35.8%
Supplemental Security	0.0%
Cash public assistance	0.0%
Food stamps / SNAP	10.4%

Health indicators

Condition	%
Obesity	23.4%
High blood pressure	22.1%
High cholesterol	25.5%
Diabetes	5.8%
Heart disease	5.1%
Stroke	2.1%
Asthma	9.9%
Arthritis	17.3%
Kidney disease	2.2%
Pulmonary disease	5.6%
Cancer	5.0%

Behavior / access	%
Smoking	11.9%
Binge drinking	20.8%
No physical activity	14.7%
Less than 7 hrs sleep	28.1%
Depression	21.5%
Fair or poor health	9.3%
Poor mental health	14.6%
Poor physical health	7.3%
No health insurance	12.5%
Visited doctor (checkup)	71.8%
Visited dentist	68.7%
Cholesterol screening	79.2%
Teeth loss	13.9%

Veterans & disability

Veterans	Count	%
Civilian veterans	83	7.2%

Disability	%
Any disability	10.3%
Under 18	0.0%
18–64 years	7.4%
65 and over	29.1%

Health insurance coverage

Type	%
Private insurance	83.7%
Public insurance	26.0%
No insurance	4.3%
Uninsured under 19	7.6%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	1,279	99.2%
Spanish	5	0.4%
Other Indo-European	0	0.0%
Asian & Pacific Islander	0	0.0%
Other languages	0	0.0%

Place of birth & citizenship

Origin	Count	%
Native born (US)	1,220	94.6%
Born in same state	1,203	93.3%
Born in different state	506	39.3%
Foreign born	17	1.3%
Naturalized citizen	69	5.4%
Not a US citizen	33	47.8%

Ancestry

Ancestry	Count	%
French	226	17.5%
Italian	157	12.2%
Arab	72	5.6%
German	38	2.9%
Polish	12	0.9%

Ancestry	Count	%
Norwegian	12	0.9%
Irish	10	0.8%
Dutch	7	0.5%
English	3	0.2%

Technology access

Metric	% of households
Computer access	24.5%
Internet access	99.7%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 04421

What city is ZIP code 04421 in?

ZIP code 04421 is primarily assigned to Castine, Maine.

What county is ZIP code 04421 in?

ZIP code 04421 falls within Hancock County, Maine.

How educated is the population of ZIP code 04421?

64% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

What is the poverty rate in ZIP code 04421?

15% of residents in ZIP code 04421 live below the poverty line, above the national average.

Does ZIP code 04421 have a large retiree population?

40% of households in ZIP code 04421 receive Social Security income, suggesting a significant retiree or disability population.

What is the typical home value in ZIP code 04421?

The median home value in ZIP code 04421 is $413,300.

What timezone is ZIP code 04421 in?

ZIP code 04421 observes the EST timezone.