Texas · Central Time
512 Area Code
Area code 512 is in Texas, serving Austin and surrounding Central Texas counties, including Round Rock and San Marcos. It is in the Central Time zone. It shares its territory with overlay code 737, so 10-digit dialing is required.
Last updated October 1, 2026 · Source: NANPA
Where is the 512 area code?
512 is a Texas area code covering Austin and surrounding Central Texas counties, including Round Rock and San Marcos. In the wider directory it sits in the South region.
Cities in the 512 area code
- Austin
- Round Rock
- Cedar Park
- Georgetown
- Pflugerville
- San Marcos
- Leander
- Kyle
- Hutto
- Buda
- Lakeway
- Bastrop
- Lockhart
- Burnet
Counties served by 512
Travis County, Williamson County, Hays County, Bastrop County, Caldwell County and Burnet County.
Time zone note: Almost all of Texas is Central; far-west El Paso is Mountain.
512 overlay codes and dialing
The 512 territory is covered by an overlay of 2 area codes: 512, 737. All of them serve the same geographic area, and the original code is 512. Because more than one code covers the same ground, 10-digit dialing is mandatory — you must dial the area code for every local call. New phone lines may be assigned any of these codes.
History of the 512 area code
512 is one of the original area codes assigned in 1947, when AT&T and Bell Laboratories created the North American Numbering Plan and divided the country into the first 86 numbering plan areas. It has served the Austin area ever since, with 737 later added as an overlay to supply more numbers.
Is 512 a scam or spam risk?
512 is a legitimate geographic area code, not a premium or toll line, so a call from it costs you nothing extra. That said, scammers frequently spoof real local area codes to look familiar on caller ID. A genuine 512 number on your screen is no guarantee the caller is in Austin, TX or trustworthy. See spam & scam-risk area codes for how spoofing works and how to respond.
Other Texas area codes
Explore more
See every code in Texas, compare codes across the South region, or view all Central Time codes. You can also browse the 5XX block or the complete numeric list of US area codes.
New to how this all works? Start with how area codes work, then read up on overlays, 10-digit dialing, and spam & scam-risk codes. To check another number, use the area code lookup tool.
Quick answers
512 area code FAQ
Where is the 512 area code?
The 512 area code is in Texas, covering Austin and surrounding Central Texas counties, including Round Rock and San Marcos, in the South region.
What cities are in the 512 area code?
Cities in the 512 area code include Austin, Round Rock, Cedar Park, Georgetown, Pflugerville, San Marcos, Leander, Kyle, Hutto and Buda.
What time zone is 512 in?
512 is in the Central Time zone. Almost all of Texas is Central; far-west El Paso is Mountain.
What is the overlay for the 512 area code?
512 shares its territory with 737. Both codes (512, 737) serve the same area, so 10-digit dialing is required for every call.
When did the 512 area code start?
512 went into service on January 1, 1947 as one of the original 1947 North American area codes.
Do I have to dial 10 digits for 512?
Yes. Because 512 is an overlay area, you must dial the full 10-digit number (area code + 7 digits) for every call.
Is 512 a toll-free or premium code?
No. 512 is a standard geographic area code, so calling it costs the same as any local or long-distance call on your plan. Toll-free calls use 800, 888, 877, 866, 855, 844 or 833.