County directory · California · 2026–27

School districts in Contra Costa County, CA

Contra Costa County has 19 regular public school districts, enrolling 156,518 students in 2024–25. The largest is Mt. Diablo Unified (29,494 students, 19% of the county), followed by San Ramon Valley Unified and West Contra Costa Unified. 17 of the 19 offer kindergarten. California's kindergarten cutoff: turn 5 by September 1.

The 19 districts, largest first

School districts in Contra Costa County, CA by 2024–25 enrollment
District and officeGradesSchoolsStudentsKindergartenDistrict office contact
Mt. Diablo Unified
1936 Carlotta Dr., Concord
K–125129,4943,079
(925) 682-8000
San Ramon Valley Unified
699 Old Orchard Dr., Danville
K–123728,6152,395
(925) 552-5500
West Contra Costa Unified
1108 Bissell Ave., Richmond
K–125425,2442,619
(510) 231-1100
Antioch Unified
510 G St., Antioch
K–122515,2531,406
(925) 779-7500
Pittsburg Unified
2000 Railroad Ave., Pittsburg
K–121310,666997
(925) 473-2300
Brentwood Union
255 Guthrie Ln., Brentwood
K–81210,0491,373
(925) 513-6300
Liberty Union High
20 Oak St., Brentwood
9–1258,228—
(925) 634-2166
Acalanes Union High
1212 Pleasant Hill Rd., Lafayette
9–1255,425—
(925) 280-3900
Oakley Union Elementary
91 Mercedes Ln., Oakley
K–895,131746
(925) 625-0700
Martinez Unified
921 Susana St., Martinez
K–1293,787401
(925) 335-5800
Walnut Creek Elementary
960 Ygnacio Valley Rd., Walnut Creek
K–873,603566
(925) 944-6850
Lafayette Elementary
3477 School St., Lafayette
K–863,235432
(925) 927-3500
Orinda Union
8 Altarinda Rd., Orinda
K–852,594388
(925) 254-4901
Moraga Elementary
1540 School St., Moraga
K–841,805262
(925) 376-5943
John Swett Unified
400 Parker Ave., Rodeo
K–1241,198116
(510) 245-4300
Byron Union Elementary
14301 Byron Hwy., Byron
K–1241,183174
(925) 809-7502
Knightsen Elementary
1923 Delta Rd., Knightsen
K–8264899
(925) 626-3310
Contra Costa County Office of Education
77 Santa Barbara Rd., Pleasant Hill
K–1252925
(925) 942-3380
Canyon Elementary
187 Pinehurst Rd., Canyon
K–81686
(925) 376-4671

Contra Costa County at a glance

Together the 19 districts run 258 schools from offices in 17 towns. The smallest by enrollment is Canyon Elementary, with 68 students; the median Contra Costa County district has 3,787. By grade span: 9 K–12, 8 K–8 and 2 9–12. Without kindergarten: Liberty Union High (9–12) and Acalanes Union High (9–12).

Kindergarten in 2024–25, counting the 17 districts that report a K grade: 15,064 children. The biggest kindergarten was Mt. Diablo Unified's, with 3,079; West Contra Costa Unified had 2,619, and the smallest, Contra Costa County Office of Education, had 5.

Contra Costa County holds 19 of California's 987 regular districts (1.9%) and 3.0% of its 5,201,297 public school students, ranking 21st of 58 counties by number of districts and 11th by enrollment. By size, 9 enroll 5,000 or more, 7 enroll 1,000 to 4,999 and 3 have fewer than 1,000 students, and the average school here has about 607 students.

Which district am I in?

Each district draws its own attendance zones, so your home address decides it. There is no address lookup here; ask the district. Each one's own site:

Mt. Diablo Unified · San Ramon Valley Unified · West Contra Costa Unified · Antioch Unified · Pittsburg Unified · Brentwood Union · Liberty Union High · Acalanes Union High · Oakley Union Elementary · Martinez Unified · Walnut Creek Elementary · Lafayette Elementary · Orinda Union · Moraga Elementary · John Swett Unified · Byron Union Elementary · Knightsen Elementary · Contra Costa County Office of Education · Canyon Elementary

What grade will my child be in?

↓ Tap Calculate to see the grade
Most US states use a September 1 cutoff. Year-stamped for the 2026–27 school year.

More in California

Every California district by county · California kindergarten cutoff

More California county directories: Fresno County (30) · Placer County (15) · San Benito County (12) · Siskiyou County (26) · Sonoma County (41) · Stanislaus County (25)

Sources

District list, grades, school counts and websites: NCES Common Core of Data (CCD) LEA Universe Directory, SY 2025-26 (preliminary, v0a), published July 1, 2026. Regular public districts only (NCES LEA types 1 and 2); charter-only, state-run and regional service agencies are not listed.
Enrollment: NCES CCD LEA Membership, SY 2024-25 (v1a), published December 29, 2025 — the newest year NCES has released.
Counties: NCES EDGE Public LEA Geocodes, SY 2024-25 (district office location) and NCES EDGE Geographic Relationship Files 2025 (grf25_lea_county) (counties each district boundary covers).
Downloaded October 20, 2026. Spot something off? Email [email protected].