Area code 346 vs 621
346 and 621 are overlay codes: they cover the same ground in Texas, and a number in one is a local call to the other. 346 is the original, in service since 2014. 621 was added in 2025 because the first was filling up – that is what an overlay is for. Today 346 has 752 of 786 blocks assigned (95.7%) and 621 has 0 of 786 (0.0%), so a new number in the area now almost always comes from 621. 346 appears in the complaint data with 709 complaints in the window; 621 does not appear at all, which is what you would expect of a code that is barely used so far. Neither code is better or safer than the other. They are the same geography, the same carriers and the same dialing rules; the difference is only how long each has existed and how full it is.
Side by side
| 346 | 621 | |
|---|---|---|
| In service since | 2014 | 2025 |
| Region | Texas | Texas |
| Blocks assigned | 752 of 786 (95.7%) | 0 of 786 (0%) |
| Largest block holder | T-Mobile 19.5% | – |
| Complaints, 28 Sep – 30 Oct 2026 | 709 (#127) | not in the data |
| Rate centers | 45 | – |
Block share is allocation by the numbering administrator, not subscribers. Complaint counts cover 28 Sep – 30 Oct 2026 and measure how often each code is spoofed on caller ID.
Frequently asked
What is the difference between area codes 346 and 621?
None geographically – they overlay the same area, so the difference is age and how many numbers are left.
Do I need to dial the area code between 346 and 621?
Yes. Overlay areas use ten-digit dialing for local calls, including between the two codes. Seven digits reaches a recording.
Will a new number be 346 or 621?
Whichever has blocks left – currently 621, at 0% allocated against 95.7% for the other. Carriers draw from the code with free blocks, which is why the newer code spreads over time.
Is 346 or 621 more likely to be a spam call?
The data does not support a comparison: only one of the two appears in the complaint window.
Sources
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- NANPA – CO Code Assignment Records, All States (utilized), file updated 11/01/2026, retrieved Nov 1, 2026
- FTC – Do Not Call Reported Calls Data, 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
Each code on its own: 346 · 621. All codes in Texas: Texas area codes.