Area Code 210

About Area Code 210

Area code 210 is a geographic telephone area code assigned to San Antonio, Texas. It operates in the Central time zone and was first introduced in 1992. Split from 512. San Antonio metro. Overlay 726 added 2017.

Within Texas, area code 210 shares numbering capacity with 27 other area codes. The state's 30,503,301-person population (2023 Census Bureau estimate) is served by a combined 28 active codes, with 210 primarily responsible for the San Antonio region. Texas's state capital is Austin, and its largest city is Houston.

When you receive a call from a 210 number on your Caller ID, the call originated from a phone number assigned to the 210 area code — but be aware that Local Number Portability (in effect since 2003) means the caller could be physically located anywhere in the US or Canada. Area code 210 only confirms where the number was originally assigned.

Where is the 210 area code located?

Area code 210 is assigned to San Antonio, Texas, in the Central time zone. The state of Texas uses 28 active area codes, and 210 is one of them. Calls placed from the 210 area code originate from numbers assigned by NANPA — the North American Numbering Plan Administrator — and the 210 prefix appears on Caller ID for both landline and wireless calls placed from this region.

The Central time zone observes Daylight Saving Time, shifting from UTC-6 to UTC-5 in summer. The local time shown above is always current, so you can quickly check whether it's a reasonable hour to call back.

What cities and counties use the 210 area code?

The 210 area code serves 11 notable cities, listed below in order of population. The largest city in the 210 territory is San Antonio (1,434,625 residents in Bexar County).

• San Antonio, TX — 1,434,625 residents (15.6% of 210 numbers)
• Houston, TX — 2,302,878 residents (25.1% of 210 numbers)
• Dallas, TX — 1,304,379 residents (14.2% of 210 numbers)
• Austin, TX — 974,447 residents (10.6% of 210 numbers)
• Fort Worth, TX — 956,709 residents (10.4% of 210 numbers)
• El Paso, TX — 678,058 residents (7.4% of 210 numbers)
• Arlington, TX — 394,266 residents (4.3% of 210 numbers)
• Corpus Christi, TX — 317,863 residents (3.5% of 210 numbers)
• Plano, TX — 285,494 residents (3.1% of 210 numbers)
• Lubbock, TX — 263,930 residents (2.9% of 210 numbers)

Phone number format in area code 210

All phone numbers within area code 210 follow the standard North American 10-digit format:(210) NXX-XXXX. The NXX is the central office prefix (also called an "exchange") and XXXX is the subscriber line number. For long-distance calls within the NANP, dial 1 + 210 + NXX + XXXX. From outside North America, dial your country's international access code, then 1 (the NANP country code), then the 10-digit number.

If you need to verify whether a specific 210 number is wireless, landline, or VoIP, you can use our reverse phone lookup tool. Be aware that number portability means the area code no longer guarantees the caller's physical location — only where the number was first assigned.

History of area code 210

Split from 512. San Antonio metro. Overlay 726 added 2017.

The original 86 area codes were assigned by AT&T and Bell Labs in 1947 as part of the North American Numbering Plan. At the time, rotary-dial phones meant codes with lower digits (like 212 for NYC, 213 for LA, 312 for Chicago) were given to the largest cities because they took less time to dial. Today's area code assignments still reflect those early choices, even though touch-tone and cell phones made the original reason obsolete.

Is the 210 area code safe to answer?

Area code 210 itself is a normal geographic code with no elevated spam risk. That said, scammers can spoof any area code — including 210 — so if you don't recognize the full number, let it go to voicemail and verify the caller's identity before calling back.