Area Code 707: Complete Guide to Northern California Coverage

Area code 707 is the telephone area code for Northern California, covering Benicia, Napa Valley, Santa Rosa, Vallejo, Eureka, and surrounding regions. If you need a 707 phone number or want to understand this area code's coverage, dialing requirements, and the 369 overlay, this guide provides everything you need to know about telephone services across 10 counties in Northern California's wine country, coastal areas, and redwood forests.

What Cities and Counties Are in Area Code 707?

The 707 area code extends beyond the famed Napa Valley vineyards to include coastal towns along the Pacific Ocean, redwood forests, and urban centers like Benicia and Santa Rosa. This area code represents more than wine country – it's a microcosm of Northern California's diverse character.

Coverage Statistics: The 707 area code (combined with its 369 overlay) serves 2,848,703 people across 10 counties as of the 2020 U.S. Census. The region encompasses approximately 1,575 square miles in Sonoma County alone, with additional coverage spanning coastal, valley, and forested terrain. The population includes major urban centers like Santa Rosa (178,127), Vallejo (within Solano County's 453,491 residents), and Napa (138,019), alongside smaller coastal and rural communities.

The 707 area code covers all or portions of the following counties:

• Sonoma (488,863 residents): Known for its wineries, picturesque landscapes, and the city of Santa Rosa.
• Solano (453,491 residents): A county with agricultural heritage and key cities like Vallejo and Benicia.
• Napa (138,019 residents): World-renowned for wine production and the city of Napa.
• Humboldt (136,463 residents): Home to redwood forests, coastal areas, and the city of Eureka.
• Mendocino (91,601 residents): Characterized by its rugged coastline and charming towns.
• Lake (68,163 residents): Known for its serene waters and recreational opportunities.
• Del Norte (27,743 residents): The northernmost county in the 707 area code, bordering Oregon.
• Glenn: Agricultural county in the northern Sacramento Valley.
• Tehama: Known for its natural resources and outdoor recreation.
• Parts of Marin (262,321 residents) and Trinity (16,112 residents): While primarily covered by other area codes, small portions of these counties fall within 707.

This broad geographic coverage contributes to the area code's complex telecommunications infrastructure, serving diverse users from wine country businesses to coastal tourism to rural agricultural communities.

Who Regulates Area Code 707?

The California Public Utilities Commission (CPUC) created area code 707 on January 1, 1959, as a split from area code 415. The CPUC regulates the area code under California Public Utilities Code sections 7930–7943, overseeing telecommunications services and infrastructure throughout California. The CPUC works with the North American Numbering Plan Administrator (NANPA), which manages telephone number assignment and allocation.

What NANPA Does: NANPA administers NANP numbering resources, including assignment of area codes and telephone number blocks to telecommunications carriers. NANPA follows regulatory directives and industry-developed guidelines but is not a policy-making entity. When you request a new phone number from your carrier, NANPA's work ensures available numbers exist and the numbering system remains organized across all 20 North American countries sharing the NANP.

The CPUC ensures fair pricing, adequate service quality, and efficient number allocation within area code 707 – serving as your advocate for reliable telecommunications services.

Number Conservation Measures: The CPUC has managed the 707 area code proactively, implementing number pooling and conservation measures to address growth and demand. Number pooling allocates telephone numbers to carriers in blocks of 1,000 consecutive numbers (rather than 10,000-number blocks per carrier), significantly improving efficiency and extending the life of existing area codes. Conservation measures include requiring carriers to utilize at least 75% of their allocated numbers before receiving additional blocks and returning unused number blocks to a central pool for reallocation. This approach delayed the need for splits or overlays for decades.

On June 23, 2022, the CPUC issued Decision 22-06-031, approving the 369 area code overlay to ensure continued telephone number availability. Visit the CPUC website at https://www.cpuc.ca.gov/ for more information or to file consumer complaints about telecommunications services.

How Do You Dial a 707 Phone Number?

10-digit dialing became mandatory in area code 707 on October 24, 2021, to support the 988 National Suicide Prevention and Mental Health Crisis Lifeline (launched July 16, 2022). Follow these device-specific dialing formats:

• Landlines: Dial 1 + area code + 7-digit number (e.g., 1-707-555-1234) for both local and long-distance calls
• Cell phones and VoIP: Dial area code + 7-digit number (e.g., 707-555-1234) without the 1 prefix

Always dial the full 10 digits for local calls within the 707 area code, with or without the 1 prefix depending on your device type.

International Dialing: To call a 707 number from outside the United States, dial your country's international access code (often 00 or +), followed by the U.S. country code +1, then the area code and 7-digit number. Example format: +1-707-555-1234. When calling internationally from the U.S. to other countries, dial 011 + country code + local number.

What Happens If You Dial Incorrectly: If you dial only 7 digits for a local call in area codes requiring 10-digit dialing, your call will not complete. You'll typically hear a recorded message stating "Your call cannot be completed as dialed" or a similar error notification instructing you to hang up and dial again using the area code. If you accidentally dial 988 as the first three digits of a 7-digit number, your call will route to the 988 Suicide & Crisis Lifeline – hang up and redial using the full 10-digit format with area code.

Telephone Service Providers in the 707 Region

AT&T, Verizon, and T-Mobile operate throughout this region, offering landline, mobile, and internet services. Compare carriers based on coverage area, data speeds, and pricing plans to find the best fit for your needs. Business phone numbers and residential telephone service with 707 area codes are widely available from these major providers, as well as smaller regional and VoIP carriers serving specific communities in wine country and coastal areas.

Regional carriers and VoIP providers in the 707 area include services like Vitel Global, VoIPLy, LinkedPhone, and DialMyCalls, which offer local 707 numbers for businesses establishing a regional presence. Coverage quality varies by location – coastal and mountainous areas may experience signal limitations, while urban centers like Santa Rosa and Napa generally have robust coverage from all major carriers.

Which Cities Use Area Code 707?

Area code 707 encompasses diverse cities and communities, each with unique character and attractions:

Additional cities served include Fairfield, Vacaville, Petaluma, Rohnert Park, Suisun City, Windsor, Dixon, Arcata, Healdsburg, Sonoma, Rio Vista, Cloverdale, Cotati, Sebastopol, Fort Bragg, Saint Helena, Calistoga, Lakeport, and many smaller communities throughout the region's 10 counties.

Frequently Asked Questions about Area Code 707

When Was Area Code 707 Created?

The CPUC established area code 707 on January 1, 1959, as a split from area code 415 to accommodate growth in Northern California. Originally, it covered a much larger area, including parts of what are now the 530 and 916 area codes. The 369 area code was introduced as an overlay on February 1, 2023, following CPUC Decision 22-06-031 (approved June 23, 2022). Both 707 and 369 now serve the same geographic area.

What Is the 369 Area Code Overlay for 707?

The 369 area code is an overlay that serves the same geographic region as 707. Implemented on February 1, 2023, the overlay allows new telephone numbers to be assigned with either 707 or 369 area codes. Your existing 707 number remains unchanged, but new customers may receive 369 numbers when 707 prefixes are exhausted.

Which major carriers operate in area code 707?

AT&T, Verizon, and T-Mobile offer mobile and landline services throughout the region. You can also find smaller regional carriers and VoIP providers (including Vitel Global, VoIPLy, LinkedPhone, and DialMyCalls) providing specialized services for businesses and residents.

Are there any current or planned changes to area code 707?

The 369 overlay on February 1, 2023, was the most recent change. As of NANPA data updated October 2025, 84.1% of available prefixes have been assigned, and the area code is not currently in jeopardy of exhaustion. The CPUC continually monitors demand and may implement future changes. Check the CPUC website periodically for updates.

How Do I Dial a 707 Phone Number?

10-digit dialing became mandatory on October 24, 2021, to support the 988 National Suicide Prevention and Mental Health Crisis Lifeline. Dial 1 + area code + 7-digit number on landlines for all calls. Dial area code + 7-digit number on cell phones and VoIP services without the 1 prefix.

When do I need to use area code 707?

Always dial the area code for all calls within the 707 region, even for local calls. This 10-digit dialing requirement has been mandatory since October 24, 2021, and applies to both 707 and 369 numbers.

What are some attractions in the 707 area?

Explore the Napa Valley wine region, historic Benicia, the North Coast's natural beauty, and majestic redwood forests. Visit Six Flags Discovery Kingdom in Vallejo and the Charles M. Schulz Museum in Santa Rosa. The area's diverse geography offers something for everyone.

Can I port my existing phone number to a different carrier in the 707 area?

Yes. FCC rules require carriers to port valid phone numbers when requested, typically completing "simple ports" (single lines) within one business day. You can keep your 707 number when switching between carriers in the same geographic area. Contact your new carrier to initiate the porting process – do not cancel service with your old carrier before the port completes.

Can I choose between getting a 707 or 369 number?

When requesting new service, carriers assign numbers based on availability. Starting February 1, 2023, new customers in the region may receive either a 707 or 369 number depending on which prefixes your carrier has available. You can request a preference, but carriers are not required to accommodate specific area code requests when numbers are limited. Both area codes serve the identical geographic region with no functional difference.

Best Practices for Area Code 707

Follow these best practices when using area code 707:

• Dial correctly for your device: Use 1 + area code + 7-digit number on landlines; use area code + 7-digit number (no 1 prefix) on cell phones and VoIP. This ensures your calls connect correctly for all local calls.
• Always dial 911 for emergencies: Emergency services (911) do not require an area code. Always dial 911 from any phone (landline, cell phone, or VoIP) for police, fire, or medical emergencies. On cell phones, 911 calls route based on your approximate location using cell tower triangulation. Know your location when calling from mobile devices to help dispatchers respond quickly.
• Save important contacts with full 10-digit numbers: Store phone numbers in your contacts with the full area code (either 707 or 369) to ensure calls connect properly under mandatory 10-digit dialing.
• Monitor CPUC updates: Check the CPUC website periodically for area code changes or updates.
• Select the right carrier: Compare carriers based on coverage area (especially important in rural and coastal areas), data speeds, and pricing plans to match your specific needs.
• Report robocalls and scams: If you receive illegal robocalls, scam calls, or spoofed calls appearing to originate from 707 numbers, file a complaint with the FCC at https://consumercomplaints.fcc.gov/ or call 1-888-225-5322. You can also report violations to the California Attorney General.

Conclusion: Connecting You to Northern California

Area code 707 represents a vibrant and diverse region of Northern California, from the wine country of Napa and Sonoma to the coastal communities of Humboldt and Del Norte. This guide covers the area code's history since 1959, regulatory oversight by the CPUC, the 2023 implementation of the 369 overlay, telecommunications landscape, and unique attractions throughout 10 counties serving 2.8 million residents.

Use the proper dialing format for your device (landlines: 1 + 10 digits; cell phones/VoIP: 10 digits) and monitor CPUC updates regularly at https://www.cpuc.ca.gov/ for any future area code changes. Whether you're a resident of Benicia, a business owner in Santa Rosa, or exploring the redwood forests of Eureka, understanding area code 707 helps you stay connected throughout Northern California.

For the latest information on telephone numbers, carrier services, or regulatory updates affecting area code 707 and 369, consult your local telephone service provider or visit the California Public Utilities Commission website. For robocall complaints and telecommunications consumer protection, visit the FCC Consumer Complaint Center.