94027 ZIP Code — Atherton, CA

San Mateo County, California

ZIP code 94027 is located in Atherton, California, within San Mateo County. It covers approximately 5.03 square miles and serves a population of 7,142 residents. This is a standard ZIP code in the Pacific (PT) timezone, served by area code 650.

About ZIP code 94027

The housing stock consists of predominantly single-family detached homes. Most homes were built in the 1950s, giving the area an established character. Median home value is $2,000,000. Owner-occupancy is high at 86%, well above the national average.

The gap between median ($250,001) and mean household income suggests income inequality — a small number of higher earners pull the average up. The poverty rate of 4% is below the national average. 35% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with professional and management as the leading industry. The average commute of 23 minutes is near the national average. Remote work is prevalent — 38% of workers work from home.

Educational attainment is high — 86% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 94027 reflects a community defined by a highly educated population, high homeownership, a high rate of remote workers, and a significant Social Security-dependent population.

7,142

population

5.03

sq mi land

Standard

ZIP type

Pacific (PT)

timezone

94027 ZIP code map

Cities in ZIP code 94027

Below are the cities the US Postal Service accepts for ZIP code 94027. Using any city not on this list may result in mail delivery delays.

City	Status
Atherton	Acceptable
Atherton	Preferred

Nearby ZIP codes

94025 Menlo Park (1.2 mi) 94061 Redwood City (2.2 mi) 94305 Stanford (2.7 mi) 94301 Palo Alto (3 mi) 94304 Palo Alto (3.8 mi) 94063 Redwood City (3.8 mi) 94303 Palo Alto (4.6 mi) 94070 San Carlos (4.6 mi) 94306 Palo Alto (4.9 mi) 94028 Portola Valley (5.6 mi) 94062 Redwood City (5.7 mi) 94065 Redwood City (6.3 mi)

Demographics updated 06/2026

Population
Total population	7,142
Population density	1,420 / sq mi
State FIPS	06
County FIPS	081

Geography
Land area	5.03 sq mi
Water area	0.03 sq mi
Latitude	37.4501
Longitude	-122.2050
Timezone	Pacific (PT)
Area code	650

Total population by age

Gender

Race & ethnicity

Economics updated 06/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	9.8%	18.4%	32.6%
$50k – $100k	9.4%	20.5%	27.7%
$100k – $200k	16.7%	30.5%	26.4%
Over $200k	64.2%	30.6%	13.3%

Demographics & statistics

7,142

Population

1,420

People per sq mi

46.4

Median age

$250,001

Median household income

$187,421

Per capita income

$2,000,000

Median home value

$3,501

Median monthly rent

85.9%

Home ownership

3.9%

Poverty rate

2.2%

Unemployment

2,288

Housing units

86.0%

Bachelor's or higher

Age distribution

Male Female

Under 5

109

5–9

110

322

10–14

322

435

15–19

435

288

20–24

289

277

25–34

278

245

35–44

245

490

45–54

491

275

55–59

275

206

60–64

207

451

65–74

452

282

75–84

283

126

85+

126

← Male

Female →

Age summary

Group	Count	%
Under 18	1,419	19.9%
18 and over	5,723	80.1%
65 and over	1,720	24.1%
Median age	46.4 years

Race & ethnicity

White 69.2%

Asian 18.8%

Two or more races 5.4%

Hispanic or Latino 3.4%

Other race 1.5%

Black or African American 1.4%

Native Hawaiian / Pacific Islander 0.2%

Group	Count	%
White	5,117	69.2%
Asian	1,390	18.8%
Two or more races	402	5.4%
Hispanic or Latino	250	3.4%
Other race	113	1.5%
Black or African American	103	1.4%
Native Hawaiian / Pacific Islander	14	0.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	9.8%	18.4%	32.6%
$50k – $100k	9.4%	20.5%	27.7%
$100k – $200k	16.7%	30.5%	26.4%
Over $200k	64.2%	30.6%	13.3%

Under $10k 2.2%

$10k–$15k 2.7%

$15k–$25k 1.0%

$25k–$35k 0.9%

$35k–$50k 2.3%

$50k–$75k 3.4%

$75k–$100k 1.9%

$100k–$150k 10.4%

$150k–$200k 7.0%

$200k+ 68.2%

Range	% of households
Under $10k	2.2%
$10k–$15k	2.7%
$15k–$25k	1.0%
$25k–$35k	0.9%
$35k–$50k	2.3%
$50k–$75k	3.4%
$75k–$100k	1.9%
$100k–$150k	10.4%
$150k–$200k	7.0%
$200k+	68.2%
Median income	$250,001

Housing

Home values

Under $50k 0.7%

$300k–$500k 0.2%

$500k–$1M 0.6%

$1M+ 98.5%

Housing overview

Metric	Value
Median home value	$2,000,000
Median rent / month	$3,501
Owner occupied	85.9%
Renter occupied	14.1%
Vacant	15.6%
Single-family detached	97.9%
Large apartment buildings	0.0%
Mobile homes	0.0%
Median rooms	10.0
Avg household size (owned)	2.97

Year built

Era	%
2020 or later	1.0%
2010–2019	10.9%
2000–2009	10.8%
1990–1999	6.1%
1980–1989	7.0%
1970–1979	3.7%
1960–1969	10.8%
1950–1959	22.1%
1940–1949	15.1%
1939 or earlier	12.6%

Bedrooms

Size	% of units
No bedroom (studio)	0.5%
1 bedroom	0.8%
2 bedrooms	3.4%
3 bedrooms	17.7%
4 bedrooms	34.7%
5+ bedrooms	43.0%

Vehicles per household

Vehicles	% of households
No vehicle	1.3%
1 vehicle	10.1%
2 vehicles	31.2%
3 or more	57.4%

Heating fuel

Fuel type	%
Utility gas	78.1%
Electricity	20.4%
Propane / LP gas	0.2%
Solar	1.0%
No fuel used	0.2%

Households & families

Household type	Count	%
Married-couple family	1,674	76.4%
Cohabiting couple	87	4.0%
Male householder, no spouse	118	5.4%
Female householder, no spouse	313	14.3%
Households with children under 18	732	33.4%
Households with seniors (65+)	1,075	49.0%
Average household size	2.97

Marital status

Status	Male	Female
Never married	39.3%	31.7%
Married	56.9%	58.0%
Separated	0.0%	2.1%
Widowed	1.3%	6.0%
Divorced	2.4%	2.3%

Education

Less than 9th grade 0.0%

Some HS, no diploma 0.5%

HS graduate 4.6%

Some college, no degree 5.1%

Associate's degree 3.7%

Bachelor's degree 29.1%

Graduate / professional 56.9%

Metric	%
HS diploma or higher	99.5%
Bachelor's or higher	86.0%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	83	3.4%
Kindergarten	34	1.4%
Elementary school	720	29.7%
High school	633	26.1%
College / grad school	952	39.3%

Employment

Industry of employment

Professional & management 24.6%

Education & healthcare 20.2%

Finance & real estate 20.0%

Manufacturing 10.3%

Arts, food & hospitality 6.9%

Information 6.3%

Retail trade 3.1%

Transportation & utilities 2.1%

Other services 2.1%

Construction 1.5%

Wholesale trade 1.4%

Public administration 1.1%

Agriculture & mining 0.2%

Occupation

Category	%
Management, business & arts	80.6%
Service	6.6%
Sales & office	11.3%
Natural resources & construction	0.4%
Production & transportation	1.1%

Employment type

Type	%
Private sector	85.3%
Government	4.6%
Self-employed	9.8%
Unpaid family workers	0.3%

Commute

Method	%
Drive alone	46.9%
Carpool	8.2%
Public transit	3.0%
Walk	2.3%
Work from home	37.5%
Other means	2.2%
Avg commute (minutes)	23.2

Poverty

All people 3.9%

Under 18 years 0.0%

18 and over 5.0%

Married-couple families 0.7%

Female-led households 0.0%

Income support

Source	% of households
Social Security	35.1%
Retirement income	23.5%
Supplemental Security	1.3%
Cash public assistance	0.5%
Food stamps / SNAP	0.0%

Health indicators

Condition	%
Obesity	20.0%
High blood pressure	28.7%
High cholesterol	36.9%
Diabetes	8.4%
Heart disease	5.8%
Stroke	2.4%
Asthma	8.4%
Arthritis	22.6%
Kidney disease	2.7%
Pulmonary disease	4.5%
Cancer	8.6%

Behavior / access	%
Smoking	6.2%
Binge drinking	15.6%
No physical activity	12.7%
Less than 7 hrs sleep	24.7%
Depression	14.1%
Fair or poor health	8.6%
Poor mental health	10.2%
Poor physical health	7.2%
No health insurance	4.9%
Visited doctor (checkup)	71.9%
Visited dentist	79.4%
Cholesterol screening	95.0%
Teeth loss	4.9%

Veterans & disability

Veterans	Count	%
Civilian veterans	190	3.3%

Disability	%
Any disability	8.1%
Under 18	1.0%
18–64 years	3.2%
65 and over	25.2%

Health insurance coverage

Type	%
Private insurance	86.4%
Public insurance	26.0%
No insurance	1.1%
Uninsured under 19	1.4%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	7,019	98.3%
Spanish	279	4.0%
Other Indo-European	24	0.3%
Asian & Pacific Islander	54	0.8%
Other languages	201	2.9%

Place of birth & citizenship

Origin	Count	%
Native born (US)	5,663	79.3%
Born in same state	5,378	75.3%
Born in different state	3,063	42.9%
Foreign born	285	4.0%
Naturalized citizen	1,479	20.7%
Not a US citizen	829	56.1%

Ancestry

Ancestry	Count	%
French	889	12.4%
Italian	505	7.1%
Arab	212	3%
English	175	2.5%
Dutch	164	2.3%

Ancestry	Count	%
Polish	150	2.1%
Norwegian	102	1.4%
German	39	0.5%
Irish	29	0.4%

Technology access

Metric	% of households
Computer access	30.7%
Internet access	97.8%

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

Frequently asked questions about ZIP code 94027

What city is ZIP code 94027 in?

ZIP code 94027 is primarily assigned to Atherton, California.

What county is ZIP code 94027 in?

ZIP code 94027 falls within San Mateo County, California.

How educated is the population of ZIP code 94027?

86% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

Is ZIP code 94027 mostly owner-occupied?

86% of occupied units in ZIP code 94027 are owner-occupied, well above the national average.

What is the median household income in ZIP code 94027?

The median household income in ZIP code 94027 is $250,001, above the national median of ~$75,000.

What is the typical home value in ZIP code 94027?

The median home value in ZIP code 94027 is $2,000,000.

What timezone is ZIP code 94027 in?

ZIP code 94027 observes the PST timezone.