667 area code — Baltimore, MD geographic

Data: NANPA public reports, current as of July 28, 2026.

State
Maryland
Major area
Baltimore
Time zone
Eastern
In service since
2012-03-24
Split from
443
Overlay complex
410 / 443 / 667
Active prefixes
433
Rate centers
102
Carriers
47
Projected exhaust
1Q 2036

The 667 area code covers Baltimore, Maryland, Eastern time zone, and dates back to March 24, 2012. It is part of the 410/443/667 overlay complex — these codes share the same territory. Note that porting and VoIP mean a 667 number can be used from anywhere — the code marks where the number was assigned.

433 central-office prefixes are currently active in this code, spread across 47 code-holding carriers. Thousands-block pooling applies to 433 prefixes, so a single prefix can belong to several carriers. Its prefixes map to 102 distinct rate centers.

NANPA projects numbering capacity for the 410/443/667 complex to exhaust in 1Q 2036.

Dialing: 10D locally, 10D to other codes (1+10 digit permissible at service provider discretion.).

Practical takeaway: the 667 label narrows geography to Maryland, the prefix narrows it to a locality, and neither authenticates a caller. Verification means calling back through a number you found yourself.

667 was created from 443 in 2012.

Largest localities in 667

Largest rate centers in area code 667
Locality (rate center)Active prefixesAlso served by
Baltimore 72 301, 410, 443
Salisbury 23 410, 443
Aberdeen 23 410, 443
Pikesville 21 410, 443
Annapolis 15 410, 443
Catonsville 12 410, 443
Columbia 11 410, 443
Towson 10 410, 443
Odenton 8 410, 443
Bel Air 7 410, 443

FAQ

Is 667 a toll-free number?

No. 667 is a geographic code; calls are billed like any other domestic call. Toll-free codes are 800, 833, 844, 855, 866, 877 and 888.

Why do 410 and 667 cover the same place?

They are overlays: when a code runs low on numbers, a new code is added over the same territory instead of splitting it. The 410/443/667 complex shares one service area, and local calls are dialed with 10 digits.

Will 667 run out of numbers?

NANPA's current forecast projects exhaust in 1Q 2036 — decades of capacity remain.

Why am I getting spam calls from 667 numbers?

Scammers spoof recognizable area codes so calls look local or familiar. A displayed 667 number does not prove the call originated there — see our guide to spotting spoofed calls.

Where is a 667 number from?

667 is assigned to Baltimore and surrounding areas of Maryland in the Eastern time zone. The three digits after the area code (the prefix) narrow it down to a rate center.