Castro Valley, California

ZIP codes in Castro Valley

Area codes for Castro Valley

• Area code 510

  In service since September 2, 1991. Shares its area with 341. Local calls are dialed with 1 plus ten digits.

• Area code 341

  In service since July 22, 2019. Shares its area with 510. Local calls are dialed with 1 plus ten digits.

Area codes here are matched from telephone rate centers, so a place near a boundary can have local numbers from either side of it.

Time zone

Castro Valley is in the Pacific Time zone.

Towns near Castro Valley

• Fairview3.5 km (2.2 mi)
• Cherryland5.1 km (3.2 mi)
• Ashland5.3 km (3.3 mi)
• Hayward5.6 km (3.5 mi)
• San Lorenzo7 km (4.3 mi)
• Norris Canyon7.5 km (4.7 mi)
• San Leandro7.6 km (4.7 mi)
• Moraga11 km (6.8 mi)