Area Code 621
Texas
Area code 621 serves Texas, primarily Houston, in the Central Time (CT) time zone. It is an overlay area code sharing territory with area code 713.
Overlay Area Codes
This area code is part of an overlay region, meaning the same geographic area is served by multiple area codes. Overlay codes were introduced to meet growing demand for phone numbers without requiring existing customers to change their numbers.
This area code shares its geographic region with: area code 281 (Houston), area code 346 (Houston), area code 713 (Houston), area code 832 (Houston).
In service since: 23-Jan-2025
Demographics
The estimated population served by area code 621 is approximately 8,101,999. The population density is 751 people per square mile, which is higher than the national average of 94. The median household income is $73,104, which is near the national median of $78,538. Approximately 35.7% of adults hold a bachelor's degree or higher, compared to the national rate of 35.0%. This rate is near the national average. The poverty rate stands at 13.5%, which is near the national rate of 12.4%.
History
Area code 621 serves as an overlay for the same territory as area code 713. It was introduced in 2025 to provide additional phone number capacity for the region. It shares its territory with area codes area code 281 and area code 346 and area code 713 and area code 832.
Demographics & Economics
- Total Population
- 8,101,999
- Population Density
- 751 people/sq miabove U.S. average (U.S.: 94 people/sq mi)
- Median Household Income
- $73,104near U.S. median (U.S.: $78,538)
- Poverty Rate
- 13.5%near U.S. average (U.S.: 12.4%)
- Unemployment Rate
- 6.0%above U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+35.7%near U.S. average (U.S.: 35.0%)High School or Lower30.9%
Statistics are population-weighted aggregations from Census ACS 5-year estimates.See Sources for details.
Geographic Coverage
State
TX
Major Cities
- Houston
- Pasadena
- Pearland
- The Woodlands
- Sugar Land
- Atascocita
- Baytown
- Spring
- Channelview
- Friendswood
- Rosenberg
- Mission Bend
- La Porte
- Deer Park
- Alvin
- Fulshear
- Sienna
- Pecan Grove
- Cloverleaf
- Fresno
- Katy
- Dickinson
- Cinco Ranch
- Stafford
and 74 more cities
Time Zone
- Central Time (CT)
Current Time
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 621).
| County | Population | Share |
|---|---|---|
| Harris, TX | 5,201,146 | 64.2% |
| Fort Bend, TX | 1,310,165 | 16.2% |
| Montgomery, TX | 473,282 | 5.8% |
| Brazoria, TX | 349,277 | 4.3% |
| Galveston, TX | 267,619 | 3.3% |
| Waller, TX | 248,151 | 3.1% |
| Chambers, TX | 130,055 | 1.6% |
| Liberty, TX | 104,248 | 1.3% |
| San Jacinto, TX | 17,816 | 0.2% |
| Polk, TX | 240 | 0.0% |
Call Context
This area code covers a geographic region across TX, including Houston and surrounding communities.
Nearby Area Codes
Area codes geographically closest to 621.
Other Area Codes in Texas
Area codes that also serve Texas, linked for easy comparison.
Frequently Asked Questions
Common questions about area code 621 and how phone numbering works.
Phone numbers assigned to area code 621 are tied to where they were originally provisioned — not the caller's current location. This code serving roughly 8102k people covers Houston in TX, so a number originally set up there will retain the 621 prefix even if the owner moves or uses VoIP. Mobile phones keep their original number when users relocate, and businesses often adopt local area codes to establish a regional presence.
Start by looking up the area code on this site to understand its geographic context — area code 621 is associated with Houston in TX. For caller-specific details, use your carrier's caller ID features or check public directories. If you suspect fraud, you can report it to the FTC. To file a complaint about robocalls or spoofed numbers, visit the FCC Consumer Complaint Center. You can also register with the National Do Not Call Registry.
When an area's available number pool runs low, regulators introduce an "overlay" code covering the same territory. Both codes coexist, and new numbers are assigned from whichever has availability. Area code 621 serves the Houston region in TX, where growing demand for phone numbers necessitated an additional code. This area code shares its region with area code 713, area code 281, area code 346. Learn more in our overlay vs split guide.