Maryland Address Generator

Maryland has 23 counties and 24 county-level jurisdictions. The extra one is Baltimore City, which is independent — it belongs to no county, and the Census Bureau counts it as a county equivalent, the same treatment Virginia gives to 38 of its cities. Baltimore City and Baltimore County are different jurisdictions with different governments and different rates, and they are adjacent, which is the worst possible arrangement for code that matches on name.

The postal shape leans hard on Washington. Maryland's largest prefixes are 207 and 206, both covering the suburbs south and east of the District of Columbia, ahead of 217 around Baltimore itself. A state whose postal centre of gravity sits outside its own borders is a good reminder that sorting geography is drawn around mail volume rather than state lines.

Maryland also holds one of the country's six cross-state prefixes, from the small end. Measured across the full dataset, prefix 205 is overwhelmingly the District's — 70 of its codes — with exactly one code in Maryland and one in Virginia. The exception is tiny, and it is still an exception: a validator that maps 205 to the District and rejects everything else will reject a genuine Maryland address.

Maryland's prefixes are also scattered rather than sequential — 206, 207, 217 and the rest do not form one unbroken run. Half the country's states do: 25 of 51 can be expressed to a validator as a single prefix range, and the other 26, Maryland included, need a set. Writing a prefix rule against a contiguous state and assuming it generalises is a quiet way to reject a whole neighbouring state's addresses.

Practically, a Maryland fixture is the one to reach for when you want a state whose jurisdiction structure is ordinary at first glance and irregular underneath: 605 codes, 14 prefixes, 431 place names, an independent city that is not in the county sharing its name, and a prefix it shares with two neighbours.

Random Maryland phone numbers here use the state's real area codes — 410, 301 and 443 — with the 555-01XX line range the North American Numbering Plan reserves for fiction, so a number such as (410) 555-0158 passes format and area-code checks yet can never ring anyone. Every profile this page generates carries one that agrees with its Maryland address; for a batch of numbers on their own, the random Maryland phone number generator draws from the same range with any US area code.

Three examples in the reserved range: (410) 555-0158, (301) 555-0104, (443) 555-0143. Area codes are geographic, so a Maryland address paired with a non-MD area code fails the consistency check that fraud systems and good validators run — which is why this page pins both to Maryland. How area codes are assigned, and why the 555 block exists, are covered in how US area codes work and why fake phone numbers start with 555.