Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — CITY/CA/ALTO

Alto ZIP codes, California

No ZIP code is named for Alto, CA; addresses there use a neighbouring town's name. The ZIP code covering it is 94941. Its area codes are 415 and 628.

USPS city name
0 ZIP codes
Overlapping the city
1 more
Population
1,024
Area codes
415, 628

NANPA lists no telephone rate centre for Alto itself, so these are the area codes of the nearest one, Mill Valley (0.0 miles). A town on an area-code boundary can differ from its neighbour.

Alto in numbers

About 1,024 people live in Alto, in 451 households. The median household income is $129,191 a year, 30% above the California median of $99,122 (US: $80,734). The median age is 42.3; 67.1% of adults 25 and over hold a bachelor's degree or higher (37.1% across California); the average commute takes 14 minutes.

Population1,024Alto1,024
Households451Alto451
Median age42.3Alto42.3California37.9US 38.9
Median household income$129,191Alto$129,191California$99,122US $80,734
Bachelor's degree or higher67.1%Alto67.1%California37.1%US 35.7%
Mean commute14.1 minAlto14.1 minCalifornia28.7 minUS 26.4 min
Population density8,127 / sq miAlto8,127 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place Alto CDP. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes covering Alto

These ZIP codes cover part of Alto but are addressed as somewhere else.

ZIP codes overlapping Alto
ZIP City Type Population Median income Median home
94941 Mill Valley , CA Standard 32,706 $209,870 $2,000,000+

Map of Alto ZIP codes

94941

The ZIP codes of Alto, CA, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Alto

The nearest larger towns are Strawberry (5,830 people, 1.1 mi), Mill Valley (14,012 people, 1.3 mi) and Corte Madera (10,077 people, 1.9 mi).

Towns near Alto
TownPopulationDistance
Strawberry 5,830 1.1 mi
Mill Valley 14,012 1.3 mi
Corte Madera 10,077 1.9 mi
Tamalpais-Homestead Valley 12,085 2.1 mi
Marin City 3,195 2.4 mi
Larkspur 12,854 2.5 mi
Kentfield 6,900 3.0 mi
Tiburon 9,012 3.3 mi
Sausalito 7,141 3.6 mi
Ross 2,606 4.7 mi
San Rafael 60,433 5.3 mi
San Anselmo 12,679 6.0 mi
Santa Venetia 3,725 7.0 mi
Fairfax 7,516 7.1 mi

More nearby: every ZIP code in Marin County · California ZIP codes

Cite this page

zipcodes.pro. “Alto, CA ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ca/alto

Underlying data is public domain or openly licensed — sources, vintages and licences.