Portola Valley, CA · standard
ZIP Code 94028
San Mateo County, California - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.
- 6,534
- 166/sq mi High-density area
- $250,000+
- Median income Above-median income area
- $2,000,000+
- Median home value Above-median home value
- 82.9%
- Bachelor's or higher Above-average bachelor's attainment
National ZIP placement
Portola Valley pairs a top-decile household income with top-decile home values, in a rural, homeowner-dominated area.
- Top 1%
- household income, US ZIPs
- Top 1%
- home value, US ZIPs
- 166
- people per sq mi
- 82%
- owner-occupied homes
Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 94028 against every reporting US ZIP.
ZIP code 94028 is a mid-sized community (a standard USPS delivery area) in Portola Valley, San Mateo County, California, home to 6,534 residents across 39.5 square miles, a density of 166 people per square mile, in the Los Angeles time zone.
ZIP 94028 skews affluent, with a median household income of $250,000+ (146% above the average California ZIP), while per-capita income is $175,395. The poverty rate is 4.4%, with unemployment at 4.3%; those measures add context to the income figure. Housing is both higher-cost and owner-heavy: median home value is $2,000,000+ (159% above the average California ZIP), while 81.9% of occupied homes are owner-occupied and median rent is $3,501.
This is a highly-educated ZIP: 82.9% of adults hold a bachelor's degree or higher, the median age is 57.2, and the average commute is -. The page also surfaces 10 ZIP codes within roughly 10 miles and 6 more in San Mateo County, so 94028 can be compared with both its immediate and county-level context.
Every figure on this page is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →
Top industries in ZIP 94028
Top 5 sectors by establishment count in Portola Valley, CA
Which industries have the most business establishments in ZIP 94028.
- Professional, scientific, and technical services
Professional, scientific, and technical services
55 establishments
- Real estate and rental and leasing
Real estate and rental and leasing
29 establishments
- Health care and social assistance
Health care and social assistance
22 establishments
- Other services (except public administration) 21
Other services (except public administration)
21 establishments
- Finance and insurance 16
Finance and insurance
16 establishments
What this shows Establishment counts come from the Census ZIP Code Business Patterns program, which counts physical business locations rather than employees or revenue.
Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 94028, Portola Valley, CA · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.
Quick Facts
6,534
Population
39.5
Area (sq mi)
166
People / sq mi
Los Angeles
Time Zone
standard
ZIP Type
Who lives in ZIP 94028?
57.2
Median Age
50.5%
Male
49.5%
Female
17.7%
Foreign-Born
Hispanic or Latino is an ethnicity category from the Census Bureau and may overlap with other categories above.
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How much do residents earn?
$250,000+
Median Household Income
+146% vs state ZIP avg
$175,395
Per Capita Income
4.4%
Poverty Rate
4.3%
Unemployment Rate
How ZIP 94028 ranks among California ZIPs
Portola Valley, CA household income vs. every California ZIP code
Median household income among 1,583 reporting California ZIPs (this ZIP's population is too small for a reliable national-corpus placement)
$250,000 Top 1% higher than 99% of 1,583 California ZIPs
Each bar is a $20K-wide band; taller bars hold more California ZIPs. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Census Bureau, ACS 5-Year Estimates · 2019–2023
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What is the education profile here?
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What does housing look like?
Housing stock: occupied vs vacant
2,808housing units
2,808
Total Housing Units
2,637
Occupied Units
171
Vacant Units
2.45
Avg Household Size
Occupancy Type
$2,000,000+
Median Home Value
+159% vs state ZIP avg
$3,501
Median Rent
1965
Median Year Built
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How have home values changed over time?
FHFA House Price Index, annual appreciation data based on repeat sales and appraisals
-5.0%
YoY Change (2021)
93
HPI Index (2000 = 100)
-7%
Total Change Since 2000
Home values in ZIP 94028 have decreased 5.0% over the past year (2021). Since 2000, this ZIP has seen -7% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | – | 98 |
| 2021 | -5.0% | 93 |
Source: Federal Housing Finance Agency (FHFA) House Price Index, All-Transactions, Five-Digit ZIP Codes (Developmental Index). Index base = 100 in year 2000. Data through 2021. ZIP codes with few transactions may show missing values.
What businesses operate in this ZIP?
Census Bureau data shows 210 business establishments in ZIP 94028, employing approximately 1,822 people with a combined annual payroll of $140,292,000.
210
Businesses
1,822
Employees
$140.3M
Annual Payroll
14
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Professional, scientific, and technical services | 55 | 26.2% |
| Real estate and rental and leasing | 29 | 13.8% |
| Health care and social assistance | 22 | 10.5% |
| Other services (except public administration) | 21 | 10.0% |
| Finance and insurance | 16 | 7.6% |
| Accommodation and food services | 13 | 6.2% |
| Retail trade | 9 | 4.3% |
| Educational services | 9 | 4.3% |
| Information | 7 | 3.3% |
| Agriculture, forestry, fishing and hunting | 6 | 2.9% |
| Administrative and support and waste management and remediation services | 6 | 2.9% |
| Arts, entertainment, and recreation | 5 | 2.4% |
| Construction | 4 | 1.9% |
| Wholesale trade | 3 | 1.4% |
Source: U.S. Census Bureau, ZIP Code Business Patterns (ZBP), 2023. Employment figures may include noise for disclosure avoidance.
Nearby ZIP Codes
Want a side-by-side? Compare 94028 vs 94304 →
ZIP 94028 vs its nearest neighbors, by population
Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 94025
Menlo Park (94025)
40,526 residents
- 94061
Redwood City (94061)
36,245 residents
- 94063
Redwood City (94063)
30,949 residents
- 94306
Palo Alto (94306)
26,469 residents
- 94022
Los Altos (94022)
18,500 residents
- 94301
Palo Alto (94301)
16,995 residents
- 94305 13,862
Stanford (94305)
13,862 residents
- 94027 7,089
Atherton (94027)
7,089 residents
- 94028 6,534
Portola Valley (94028)
6,534 residents
What this shows Among its immediate neighbors, ZIP 94028 ranks #9 by population - useful context the national average alone can't give.
ZIP 94028 vs its nearest neighbors, by median income
Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 94028
Portola Valley (94028)
$250,000 median income
- 94020
La Honda (94020)
$250,000 median income
- 94022
Los Altos (94022)
$250,000 median income
- 94027
Atherton (94027)
$250,000 median income
- 94301
Palo Alto (94301)
$242,006 median income
- 94025
Menlo Park (94025)
$216,601 median income
- 94306
Palo Alto (94306)
$210,000 median income
- 94304
Palo Alto (94304)
$154,141 median income
- 94061
Redwood City (94061)
$146,265 median income
What this shows By household income, ZIP 94028 ranks the highest of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.
| ZIP Code | City | Population | Distance |
|---|---|---|---|
| 94304 | Palo Alto, CA | 3,627 | 2.3 mi |
| 94305 | Stanford, CA | 13,862 | 3.6 mi |
| 94027 | Atherton, CA | 7,089 | 5.2 mi |
| 94022 | Los Altos, CA | 18,500 | 4.2 mi |
| 94061 | Redwood City, CA | 36,245 | 5.9 mi |
| 94020 | La Honda, CA | 1,559 | 6.6 mi |
| 94306 | Palo Alto, CA | 26,469 | 5.3 mi |
| 94063 | Redwood City, CA | 30,949 | 8.0 mi |
| 94025 | Menlo Park, CA | 40,526 | 6.3 mi |
| 94301 | Palo Alto, CA | 16,995 | 5.8 mi |
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 94028, both outside CA so the neighborhoods are not geographic containment (Nearby and same-county blocks stay local).
Similar population
Nearest cross-state ZIPs by resident population (6,534 here; floor ≥1,000).
Similar median household income
Nearest cross-state ZIPs by ACS median household income.
More ZIP Codes in San Mateo County
Related Areas
Frequently Asked Questions
What county is ZIP code 94028 in?
ZIP code 94028 (Portola Valley) is located in San Mateo County, California. San Mateo County contains multiple ZIP codes, see the full list at /counties/san-mateo-ca.
What is the population of ZIP code 94028?
ZIP code 94028 in Portola Valley, CA has a population of 6,534 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 94028?
The median household income in ZIP 94028 is $250,000+, which is 228% above the national average of $76,288.
What is the average home value in ZIP 94028?
The median home value in ZIP 94028 is $2,000,000+, which is 619% above the national average of $278,155.
What is the demographic makeup of ZIP 94028?
The largest racial group in ZIP 94028 is White at 76.6%. Hispanic or Latino residents make up 11.3% of the population.
How many businesses are in ZIP code 94028?
ZIP code 94028 has 210 business establishments employing approximately 1,822 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 94028?
The top industries by establishment count in ZIP 94028 are: Professional, scientific, and technical services (55), Real estate and rental and leasing (29), Health care and social assistance (22). There are 14 industry sectors represented in total.
How have home values changed in ZIP code 94028?
According to the FHFA House Price Index, home values in ZIP 94028 decreased by 5.0% in 2021. Since 2000, home values in this ZIP have declined by approximately 7%. This is a developmental index based on repeat sales and appraisal data from Fannie Mae and Freddie Mac.
What is the education level in ZIP code 94028?
In ZIP code 94028, 85.6% of residents aged 25+ have a high school diploma or higher, and 82.9% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What percentage of residents own vs. rent in ZIP 94028?
In ZIP code 94028, approximately 81.9% of occupied housing units are owner-occupied and 18.1% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 94028?
The poverty rate in ZIP code 94028 is 4.4% according to Census Bureau ACS 2023 estimates. This measures the percentage of the population living below the federal poverty threshold.
Related
Take this with you
What to do with ZIP 94028's numbers, next.
- See how ZIP 94028 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Portola Valley, CA ranks among every U.S. ZIP code on income, education, or homeownership View national rankings
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ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.