Area Code 210: San Antonio, Texas | Location, Cities & Dialing Guide

Area code 210 is the primary telephone area code for San Antonio, Texas, and surrounding cities in south-central Texas. Part of the North American Numbering Plan (NANP), the 210 area code serves Bexar County alongside overlay area code 726. Whether you're looking for a San Antonio phone number, need to know what area code is 210, or want to understand where area code 210 is located, this comprehensive guide covers everything: 210 area code cities, mandatory 10-digit dialing requirements, the 210/726 overlay system, and how to get a local 210 telephone number for business or personal use.

What is Area Code 210?

Area code 210 is the telephone area code serving San Antonio, Texas, and its metropolitan area. Established on November 1, 1992, the 210 area code split from area code 512 to accommodate the rapidly growing San Antonio region's telecommunications needs. Today, area code 210 handles millions of phone calls daily across landline, wireless, and VoIP services.

Where is Area Code 210 Located?

The 210 area code location covers the San Antonio metropolitan area in south-central Texas. Area code 210 (coordinates: 29°25′30″N 98°29′38″W) serves most of Bexar County and portions of Atascosa, Comal, Guadalupe, Medina, and Wilson counties.

What Cities and Towns Use Area Code 210?

The San Antonio area code includes these cities and communities:

• San Antonio (primary city)
• Alamo Heights
• Castle Hills
• Converse
• Helotes
• Kirby
• Leon Springs
• Schertz
• Terrell Hills
• Universal City
• Windcrest

Area codes 210 and 726 form an enclave completely surrounded by area code 830, similar to area code 312 in Chicago or 412 in Pittsburgh.

Area Code 210 and 726 Overlay

Area code 726 serves the same geographic region as 210 in an overlay configuration. Activated on October 23, 2017, the 726 overlay addressed number exhaustion concerns. Notably, 726 spells "SAN" on telephone keypads, creating a memorable connection to San Antonio's identity.

Key Overlay Details

• Primary Code: 210 (since November 1, 1992)
• Overlay Code: 726 (since October 23, 2017)
• Type: All-services overlay
• Time Zone: Central Time (GMT -06:00)
• Dialing: 10-digit dialing required for all calls

How to Dial Area Code 210

Ten-digit dialing is mandatory for all calls within the 210/726 area code region, including local calls.

Dialing Requirements

Format: Area code + seven-digit phone number

Example: To call a San Antonio number, dial 210-555-1234 (even for local calls)

Effective date: September 23, 2017

Different locations in the same geographic area can have identical seven-digit numbers with different area codes (210 or 726). Always include the area code when dialing. Calls without area codes will fail.

Common Dialing Scenarios

• Local calls within San Antonio: Dial 210-555-1234 (10 digits required)
• Calling from elsewhere in Texas: Dial 1-210-555-1234
• Calling from outside Texas: Dial 1-210-555-1234
• International calls to 210: Dial +1-210-555-1234
• Emergency services (911): Dial 911 (area code not required)

What Phone Companies Serve Area Code 210?

Major telecommunications carriers serving the San Antonio 210 area code:

• AT&T – Landline, wireless, and fiber services
• Verizon – Wireless and business services
• T-Mobile – Wireless services (includes former Sprint customers)

Available service types:

• Landline: Traditional wired telephone connections
• Wireless: Mobile phone and cellular communication
• VoIP: Internet-based phone service for business and residential use

When Was Area Code 210 Created? History & Timeline

The 210 area code history reflects San Antonio's rapid growth:

• November 1, 1992: Area code 210 established, splitting from 512. Austin retained 512 to spare state agencies the expense of changing numbers.
• July 7, 1997: Rapid growth and cellular phone proliferation forced a three-way split within five years. Bexar County retained 210, suburbs and Hill Country became 830, and the Rio Grande Valley became 956.
• August 2016: Public Utility Commission of Texas (PUCT) announced area code 726 overlay to address projected exhaustion by mid-2018.
• March 25, 2017: Permissive ten-digit dialing begins, allowing both seven- and ten-digit dialing.
• September 23, 2017: Ten-digit dialing becomes mandatory for all calls within the 210/726 region.
• October 23, 2017: Area code 726 activated as overlay.

San Antonio Telephone History

According to a San Antonio Daily Express article from June 11, 1893, George Washington Brackenridge claimed to have installed a telephone around 1873 – three years before Alexander Graham Bell's 1876 patent. While some sources credit Galveston with Texas's first telephone in 1878, the exact nature and date of Brackenridge's early system remains historically debated and lacks independent verification.

Technical Specifications

Key specifications for telecommunications professionals working with area code 210:

• NPA (Numbering Plan Area) Code: 210
• Type: Overlay complex with area code 726
• Implementation Date: November 1, 1992
• State: Texas
• Time Zone: Central Time (GMT -06:00)
• Overlay Code: 726 (activated October 23, 2017)
• Active Prefixes (2024): 770 total (59.87% landline, 40.13% wireless)

Use these details when designing systems for phone number validation, routing, and telecommunications applications.

Regulatory Information

The Public Utility Commission of Texas (PUCT) regulates area code 210. According to the PUCT's official mission statement, the agency "regulates the state's electric, telecommunication, and water and sewer utilities, implements respective legislation, and provides customer assistance in resolving consumer complaints."

The PUCT ensures consumer protection, fair pricing, and proper management of numbering resources for telephone services throughout Texas. Area code assignments are managed by the North American Numbering Plan Administrator (NANPA) in coordination with the PUCT.

Official resources:

• PUCT: https://www.puc.texas.gov/
• PUCT Area Codes: https://www.puc.texas.gov/industry/maps/areacodes/txareacodes/
• PUCT Email for Area Code Questions: areacode@puc.texas.gov
• PUCT Phone: 512-936-7000
• PUCT Address: William B. Travis Building, 1701 N. Congress Ave, Suite 7-110, Austin, TX 78701
• NANPA Area Code Search: https://nationalnanpa.com/area_codes/index.html

Frequently Asked Questions About Area Code 210

Where is area code 210 located?

Area code 210 is located in San Antonio, Texas, and the surrounding metropolitan area in south-central Texas, covering most of Bexar County and portions of five surrounding counties (Atascosa, Comal, Guadalupe, Medina, and Wilson).

What cities are in the 210 area code?

San Antonio is the primary city in area code 210. Other cities include Alamo Heights, Castle Hills, Converse, Helotes, Kirby, Leon Springs, Schertz, Terrell Hills, Universal City, and Windcrest.

Do I need to dial the area code for local calls in San Antonio?

Yes. Ten-digit dialing is required for all calls in the 210/726 area code region, including local calls. Dial the area code + seven-digit number (e.g., 210-555-1234). This requirement has been in effect since September 23, 2017.

What is the difference between 210 and 726 area codes?

Both 210 and 726 area codes serve the same geographic region in San Antonio. Area code 726 is an overlay added in 2017 to provide additional phone numbers as 210 approached exhaustion. New phone numbers may be assigned either 210 or 726.

What does area code 726 spell on a phone keypad?

Area code 726 spells "SAN" on the alphanumeric telephone keypad (7=P/Q/R/S, 2=A/B/C, 6=M/N/O), creating a connection to San Antonio.

What time zone is area code 210 in?

Area code 210 is in the Central Time Zone (CT), which is GMT -06:00 (or GMT -05:00 during daylight saving time).

How do I get a 210 area code phone number?

Contact major telecommunications providers serving San Antonio—AT&T, Verizon, or T-Mobile—to request a 210 or 726 area code number. VoIP providers also offer San Antonio phone numbers for business and personal use. Available options include:

• Local landlines for residential service
• Mobile numbers from wireless carriers
• VoIP business lines with advanced features
• Virtual phone numbers that work anywhere in the US

Business customers can request multiple consecutive numbers in the 210 or 726 area code for call centers, departments, or multi-line systems.

When was area code 210 created?

Area code 210 was created on November 1, 1992, when it split from area code 512 to serve the San Antonio region.

Is Area Code 210 Running Out of Numbers?

No. Mobile phones and wireless devices contributed to area code 210's rapid exhaustion within five years of creation, but the 2017 overlay resolved capacity concerns. As of 2024:

• 770 active prefixes out of 800 possible (96.25%)
• 40.13% (309 prefixes) assigned to wireless numbers
• 59.87% (461 prefixes) allocated to landlines
• 30 inactive prefixes remain unassigned (3.75%)
• Most recent prefix assignment: October 16, 2024

Current Status: According to NANPA, area code 210 is not in jeopardy of exhaustion. No relief planning is currently underway, indicating the 2017 overlay with 726 successfully addressed number availability concerns.

Related Texas Area Codes

Understanding nearby Texas area codes helps you navigate the state's telecommunications network:

• Area code 726: San Antonio (overlay with 210)
• Area code 830: Surrounding San Antonio suburbs and Hill Country – see complete 830 area code coverage map, cities, and phone number options
• Area code 512 and 737: Austin and surrounding areas – find 512 area code locations and Austin phone services plus 737 overlay dialing requirements
• Area code 956: Rio Grande Valley region – explore 956 area code cities from McAllen to Brownsville
• Area code 210 vs 512: Austin retained 512 when San Antonio split to 210 in 1992

Browse the complete Texas area codes directory with maps, dialing rules, and local phone number services across all regions.

Summary

Area code 210 serves as a vital component of San Antonio's communication infrastructure and cultural identity. From its 1992 inception to its current overlay configuration with 726, the San Antonio area code continuously adapts to the region's telecommunications needs. Whether you're searching "where is area code 210" or "what area code is 210," need mandatory 10-digit dialing information, or want to get a San Antonio phone number for your business or personal use, this guide provides complete coverage of area code 210's location, history, technical specifications, and regulatory framework.

Key facts about area code 210:

• Serves San Antonio, Texas, and Bexar County
• Overlaid with area code 726 since October 2017
• Requires 10-digit dialing for all calls (mandatory since September 23, 2017)
• Central Time Zone (GMT -06:00)
• Established November 1, 1992 (split from area code 512)
• Not in jeopardy of exhaustion—new 210 and 726 numbers available
• Available through AT&T, Verizon, T-Mobile, and VoIP providers

Ready to get your San Antonio area code 210 phone number? Contact local telecommunications providers or VoIP services to secure your 210 or 726 number today.