Vienna, MD — rate center
The Vienna rate center (Maryland) anchors 4 active prefixes under area codes 410, 443, 667. Rate centers, not city limits, are what phone numbers are legally tied to.
4 central-office prefixes are currently anchored to this rate center across 4 carriers. 4 prefixes participate in thousands-block pooling, so blocks of 1,000 numbers are shared between carriers.
Routing-wise it sits in LATA 242.
Multiple area codes over one rate center (410/443/667) is the overlay pattern: same geography, different first three digits.
With only 4 prefixes, Vienna sits at the small end of Maryland's rate centers — a handful of carrier blocks cover the whole locality, and a number from here is a fairly strong locality signal (before porting is considered).
Treat this data as geography of the number, not of the caller: porting, VoIP and caller-ID spoofing all detach the two. When a call matters, hang up and call back through an official number.
Prefixes anchored to Vienna
| Prefix | Code holder | Pooled |
|---|---|---|
| 410-376 | VERIZON MARYLAND, INC. | Yes |
FAQ
What area code is Vienna, MD?
Vienna is served by 3 area codes — 410, 443, 667 — which overlay the same territory.
How many prefixes does Vienna have?
4 active NXX prefixes are anchored to this rate center in NANPA records, held by 4 carriers.
Is a call from a Vienna prefix really from Vienna?
Not necessarily. The prefix marks where the number block was issued; porting, VoIP and spoofing all detach calls from that geography.