Area Code 512 — Austin, Texas

NANP area code

512

UTC−6, UTC−5 during daylight saving

State
Texas
Primary city
Austin
Time zone
Central
In service
1947
Overlay
737

The code reaches 57 communities and 13 counties across Texas.

Was this call legitimate?

The area code itself carries no risk signal. 512 is assigned to Austin, Texas, so a call from it is consistent with a real caller in that area — but the digits alone prove nothing, because they can be forged.

Caller ID is set by whoever places the call, not verified by the network. That is why neighbour spoofing works: an operation anywhere in the world can display a number that matches the area code — and often the first three digits after it — of the person being called, so the call looks local. Every community in the 512 territory is a plausible-looking origin for a forged 512 number, which is why one can be made to look like a neighbour to so many people. The same applies to its overlay code 737, which serves the same ground.

If you did not recognise the call: let it go to voicemail — a legitimate caller with real business will leave one. Do not return the call using the number shown; look the organisation up independently and call the number you found. Never confirm personal details, card numbers, or one-time codes to someone who called you, however plausible the number looked.

Codes.zone publishes no complaint counts, risk scores, or caller identities. We hold no data on individual numbers and will not estimate what we cannot source.

Local time and when to call back

Time there now

Central · UTC−6, UTC−5 during daylight saving

Reasonable callback window

8:00 AM – 9:00 PM

local time in Central

Federal rules bar telemarketing calls to a residence outside 8:00 AM–9:00 PM in the called party's own time zone. It is a sensible bound for a personal callback too — and a caller who rang you well outside it was not observing it.

Overlay codes and ten-digit dialling

512 does not have its territory to itself. 737 covers the same ground, serving Austin and the rest of the 512 territory. An overlay is what a regulator adds when a region runs out of assignable numbers: rather than splitting the area and forcing half the residents to change their number, a second code is laid over the top and new numbers are issued from it.

The practical consequence: two neighbours on the same street can hold numbers in different area codes, so the code tells you nothing about which part of town a caller is in — and local calls must be dialled as all ten digits, because seven is no longer unambiguous.

Cities served

largest 20 by ZIP count
Communities served by area code 512, ranked by how many ZIP codes each holds.
CityZIP codesCounty
Austin74Travis County
Corpus Christi30Nueces County
Round Rock6Williamson County
Georgetown4Williamson County
Leander3Travis County
Cedar Park2Williamson County
Pflugerville2Travis County
San Marcos2Hays County
Bastrop1Bastrop County
Bend1Lampasas County
Bertram1Burnet County
Briggs1Burnet County
Buchanan Dam1Llano County
Buda1Hays County
Burnet1Burnet County
Cedar Creek1Bastrop County
Copperas Cove1Coryell County
Coupland1Williamson County
Dale1Caldwell County
Del Valle1Travis County

37 further communities not listed. All Texas area codes →

Each point is a community served by 512, plotted from its record coordinates. The outline is the convex envelope of those points — a footprint, not a boundary.
  • Reference points and footprint
  • Not an official NANPA boundary
  • Not a USPS delivery area

Scope every community matched to 512. Source geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot), GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated . Coordinates are place reference points, not boundaries.

Counties

Prefixes inside 512

We do not publish the NXX prefixes inside 512. The assignment of prefixes to rate centres comes from LERG routing data, which is proprietary, and we will not estimate it from postal data — ZIP codes and telephone prefixes do not map onto each other. Awaiting a clean-rights NPA-NXX source.

Why this code exists

512 has served this territory since 1947. It eventually ran short of exchanges to hand out, and rather than split the region and make half its residents change their number, the regulator laid 737 over the same ground in 2013. New lines here are issued from the newer code, which is why a neighbour’s number may not start with 512.