MCIMETRO ACCESS TRANSMISSION SERVICES LLC

46 prefixes in 443 · initial assignments from the NANPA CO code file, 09/17/2026

Prefixes held by MCIMETRO ACCESS TRANSMISSION SERVICES LLC in area code 443
NPA-NXX	Rate center	OCN	Assigned	Pooled
443-200	WOODLAWN	7229	2001-02-21	Yes
443-276	COLUMBIA	7229	—	Yes
443-279	TOWSON	7229	—	Yes
443-281	COCKEYSVL	7229	—	Yes
443-288	ELLICOTTCY	7229	—	Yes
443-308	SEVERN	7229	—	Yes
443-334	PIKESVILLE	7229	2001-03-14	Yes
443-400	BRYNPKLNCM	7229	—	Yes
443-407	DUNDALK	7229	—	Yes
443-408	SPARROWSPT	7229	—	Yes
443-430	COLUMBIA	7229	2001-05-18	Yes
443-433	ANNAPOLIS	7229	2001-02-21	Yes
443-440	ANNAPOLIS	7229	—	Yes
443-458	ANNAPOLIS	7229	—	Yes
443-460	ESSEX	7229	—	Yes
443-498	CATONSVL	7229	—	Yes
443-503	DUNDALK	7229	—	Yes
443-524	BALTIMORE	7229	—	—
443-548	PIKESVILLE	7229	—	Yes
443-557	GLENBURNIE	7229	—	Yes
443-558	ABERDEEN	7229	2001-01-15	Yes
443-568	ARBUTUS	7229	—	Yes
443-576	RANDALLSTN	7229	2001-02-21	Yes
443-588	PARKVILLE	7229	—	Yes
443-637	ARGRGBSNIS	7229	2001-02-21	Yes
443-650	REISTERSTN	7229	2001-02-20	Yes
443-692	BALTIMORE	7229	—	Yes
443-701	ARBUTUS	7229	—	Yes
443-703	BALTIMORE	7229	—	Yes
443-710	CATONSVL	7229	—	Yes
443-720	ABERDEEN	7229	2012-11-27	Yes
443-753	WATERLO236	7229	—	Yes
443-773	BRYNPKLNCM	7229	—	Yes
443-779	ABERDEEN	7229	—	Yes
443-782	ANNAPOLIS	7229	—	Yes
443-793	PARKVILLE	7229	—	Yes
443-795	SEVERN	7229	—	Yes
443-796	PIKESVILLE	7229	—	Yes
443-797	TOWSON	7229	—	Yes
443-815	ESSEX	7229	—	Yes
443-816	SEVERNA PK	7229	—	Yes
443-817	ARGRGBSNIS	7229	—	Yes
443-836	BALTIMORE	7229	2013-01-21	Yes
443-891	GLENBURNIE	7229	—	Yes
443-893	WOODLAWN	7229	—	Yes
443-973	ELLICOTTCY	7229	—	Yes

These are initial assignees from NANPA CO-code records — because of number portability, the current serving carrier of individual numbers may differ. Bulk export requires a membership.