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Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

Area code 443 prefixes

785 of the 786 possible NXX blocks are assigned in area code 443 (99.9% of capacity), spread across 81 rate centers and 26 holders. The largest holders are PAETEC ITEL, LLC (153 blocks, 19.5%), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD (121 blocks, 15.4%), OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC (94 blocks, 12.0%). Grouped by brand, Verizon accounts for 229 blocks; brand-attributable holders cover 95% of the code, and the rest are CLECs, VoIP wholesalers and regional carriers that trade under their own names. The assignment records here run from 2001-01-10 to 2023-11-21, with 88 blocks handed out in 2001 alone. 701 blocks (89%) are in thousands-block pooling, meaning the block is shared between carriers in 1,000-number lots rather than held whole – which is why a single NXX can serve several carriers at once. 140 were growth assignments – additional blocks to a carrier that had already filled its earlier ones.

785 assigned blocks of 786
81 rate centers
26 holders of record
89% in thousands-block pooling

Largest holders in 443

Holder of record, as NANPA names itBrandBlocksShare
PAETEC ITEL, LLC Windstream 153 19.5%
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD Verizon 121 15.4%
OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC T-Mobile 94 12%
NEW CINGULAR WIRELESS PCS, LLC - DC AT&T 71 9%
LEVEL 3 COMMUNICATIONS, LLC - MD Lumen 69 8.8%
VERIZON MARYLAND, INC. Verizon 55 7%
TELEPORT COMMUNICATIONS AMERICA, LLC - MD AT&T 48 6.1%
MCIMETRO ACCESS TRANSMISSION SERVICES LLC Verizon 46 5.9%
CORE COMMUNICATIONS, INC.- MD – 34 4.3%
METROPCS, INC. T-Mobile 25 3.2%
BANDWIDTH.COM CLEC, LLC - MD Bandwidth 18 2.3%
ONVOY, LLC - MD Onvoy 14 1.8%

Names are printed as they appear in the assignment records, which is the legal entity rather than the brand. Holding a block is not the same as serving the numbers in it: portability moves numbers between carriers and pooling splits a block between several.

Rate centers with their own page

Rate centers where at least three blocks are assigned, excluding the numbered metro zone codes. The remainder are in the full table below.

BALTIMORE 185ANNAPOLIS 39TOWSON 33COLUMBIA 31GLENBURNIE 26CATONSVL 22PIKESVILLE 21SALISBURY 20BEL AIR 19WESTMINSTR 15ABERDEEN 15ELKTON 14PARKVILLE 14ESSEX 14COCKEYSVL 14WOODLAWN 13DUNDALK 10SEVERNA PK 10FALLSTON 10ARBUTUS 10EASTON 9RANDALLSTN 9SEVERN 9SYKESVILLE 9ELLICOTTCY 9PRINCEFRCK 9EDGEWOOD 9ELKRIDGE 9REISTERSTN 8ARGRGBSNIS 8CAMBRIDGE 7BRYNPKLNCM 7CHASE 6SPARROWSPT 6ODENTON 5NORTH EAST 5FORK 5HAMPSTEAD 5WEST RIVER 4PERRYVILLE 4HAVREGRACE 4SPARKSGLNC 4CHESTERTN 4WORTHINGTN 4CARDIFF 4NORTHBEACH 4CROFTON 4MILLERSVL 4DELMAR 4CHURCHVL 4JARRETTSVL 4PT DEPOSIT 3PARKTON 3GLENWOOD 3TANEYTOWN 3SILVER RUN 3OCEAN CITY 3NEWWINDSOR 3

All 785 assigned blocks

One row per NXX. “Pooled” means carriers draw 1,000-number lots from the block rather than holding all 10,000, so a pooled prefix can belong to several carriers at once. “Not in service” means assigned but not yet open for calls – a caller ID from one of those is necessarily spoofed. The holder column gives the brand where the legal entity maps to one; the full legal names are in the holders table above, exactly as NANPA records them.

PrefixHolder of recordRate centerAssignedPooledIn service
443-200 Verizon WOODLAWN 2001-02-21 yes yes
443-201 AT&T WESTMINSTR – yes yes
443-202 Verizon BALTIMORE 2012-01-09 yes yes
443-203 Verizon WEST RIVER – yes yes
443-204 AT&T PIKESVILLE 2003-05-15 yes yes
443-205 Verizon CAMBRIDGE – yes yes
443-206 Verizon PERRYVILLE – yes yes
443-207 T-Mobile ELKTON – yes yes
443-208 T-Mobile BALTIMORE 2011-02-01 yes yes
443-209 Windstream HAVREGRACE – yes yes
443-210 T-Mobile SALISBURY 2011-09-30 yes yes
443-212 Windstream SPARKSGLNC – yes yes
443-213 Verizon PIKESVILLE – yes yes
443-214 AT&T ANNAPOLIS 2011-10-11 yes yes
443-215 CORE COMMUNICATIONS, INC.- MD CHESTERTN – – yes
443-216 Windstream DUNDALK – yes yes
443-217 CORE COMMUNICATIONS, INC.- MD ANNAPOLIS – – yes
443-218 Lumen WORTHINGTN – yes yes
443-219 Lumen PARKVILLE – yes yes
443-220 Verizon BALTIMORE – yes yes
443-221 Lumen ANNAPOLIS – yes yes
443-222 Onvoy WORTHINGTN – yes yes
443-223 Verizon ANNAPOLIS – – yes
443-224 Verizon BALTIMORE – yes yes
443-225 T-Mobile CAMBRIDGE 2004-01-20 yes yes
443-226 T-Mobile BALTIMORE – yes yes
443-227 Windstream PT DEPOSIT – yes yes
443-228 Windstream CHASE – yes yes
443-229 Windstream SEVERNA PK 2001-05-10 yes yes
443-230 Windstream ODENTON – yes yes
443-231 AT&T ESSEX – yes yes
443-232 CORE COMMUNICATIONS, INC.- MD WILLARDS – yes yes
443-233 Windstream VIENNA – yes yes
443-234 Windstream SNOW HILL – yes yes
443-235 Verizon SALISBURY – – yes
443-236 CORE COMMUNICATIONS, INC.- MD CARDIFF – – yes
443-237 CORE COMMUNICATIONS, INC.- MD NORTHBEACH – – yes
443-238 Windstream PARKTON – yes yes
443-239 AT&T EASTON 2004-01-20 yes yes
443-240 AT&T BALTIMORE 2012-01-27 yes yes
443-241 Onvoy WESTMINSTR – – yes
443-242 Windstream SPARROWSPT 2001-05-10 yes yes
443-243 Verizon FALLSTON – – yes
443-244 Lumen WESTMINSTR – yes yes
443-245 Windstream ELKTON – yes yes
443-246 CORE COMMUNICATIONS, INC.- MD ELKTON – – yes
443-247 Windstream UNION BDG – yes yes
443-248 Verizon BALTIMORE 2007-01-15 yes yes
443-249 Verizon STEVENSVL – yes yes
443-250 T-Mobile BALTIMORE – yes yes
443-251 Onvoy CATONSVL – yes yes
443-252 Verizon PERRYVILLE 2009-09-08 yes yes
443-253 AT&T BALTIMORE – – yes
443-254 T-Mobile ANNAPOLIS – – yes
443-255 AT&T BALTIMORE – – yes
443-256 Windstream NORTH EAST – yes yes
443-257 Verizon BALTIMORE – yes yes
443-258 AT&T EASTON – yes yes
443-259 Verizon COLUMBIA – yes yes
443-260 Verizon SALISBURY – yes yes
443-261 Verizon SEVERNA PK – yes yes
443-262 Verizon CENTREVL – yes yes
443-263 Verizon BALTIMORE – – yes
443-264 CORE COMMUNICATIONS, INC.- MD PIKESVILLE – yes yes
443-265 Windstream FORK 2001-05-10 yes yes
443-266 Bandwidth GLENWOOD – yes yes
443-267 AT&T DARLINGTON – yes yes
443-268 CORE COMMUNICATIONS, INC.- MD BALTIMORE – – yes
443-269 CORE COMMUNICATIONS, INC.- MD TOWSON – yes yes
443-270 Windstream GLENBURNIE – – yes
443-271 T-Mobile BALTIMORE 2002-10-21 yes yes
443-272 AT&T RANDALLSTN – yes yes
443-273 AT&T REISTERSTN – yes yes
443-274 Verizon SEVERN – yes yes
443-275 Comcast TOWSON – yes yes
443-276 Verizon COLUMBIA – yes yes
443-277 T-Mobile SYKESVILLE – yes yes
443-278 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD BALTIMORE 2003-10-02 yes yes
443-279 Verizon TOWSON – yes yes
443-280 AT&T SYKESVILLE – yes yes
443-281 Verizon COCKEYSVL – yes yes
443-282 T-Mobile CHESTERTN 2004-10-04 yes yes
443-283 Windstream COLUMBIA – – yes
443-284 CORE COMMUNICATIONS, INC.- MD WATERLO238 – yes yes
443-285 Verizon COLUMBIA – yes yes
443-286 Verizon BALTIMORE – – yes
443-287 Verizon BALTIMORE – – yes
443-288 Verizon ELLICOTTCY – yes yes
443-289 Verizon WESTMINSTR 2011-05-16 yes yes
443-290 Lumen PARKVILLE – yes yes
443-291 Lumen HAMPSTEAD – yes yes
443-292 Lumen CROFTON – yes yes
443-293 Verizon WESTMINSTR – yes yes
443-294 Bandwidth WEST RIVER – yes yes
443-295 Lumen PRINCEFRCK – yes yes
443-296 Lumen WATERLO238 – yes yes
443-297 AT&T ARBUTUS – yes yes
443-298 AT&T EASTON 2002-11-15 yes yes
443-299 Verizon FALLSTON – yes yes
443-300 Lumen SYKESVILLE – yes yes
443-301 AT&T BALTIMORE 2012-04-05 yes yes
443-302 Lumen CROFTON – yes yes
443-303 Lumen ABERDEEN – yes yes
443-304 Bandwidth ARBUTUS – yes yes
443-305 Lumen ARGRGBSNIS – yes yes
443-306 T-Mobile SEVERNA PK – yes yes
443-307 Lumen BEL AIR – yes yes
443-308 Verizon SEVERN – yes yes
443-309 T-Mobile ELKTON – yes yes
443-310 AT&T BALTIMORE – – yes
443-312 Lumen BRYNPKLNCM – yes yes
443-313 Lumen FORK – yes yes
443-314 T-Mobile BALTIMORE 2011-02-01 yes yes
443-315 AT&T CATONSVL – yes yes
443-316 Lumen WOODLAWN – yes yes
443-317 Bandwidth CHASE – yes yes
443-318 Windstream COCKEYSVL – yes yes
443-319 Windstream COLUMBIA – yes yes
443-320 Lumen BALTIMORE – yes yes
443-321 Windstream ANNAPOLIS – – yes
443-322 Windstream TOWSON 2001-05-10 yes yes
443-323 Windstream SHARPTOWN – yes yes
443-324 T-Mobile BALTIMORE – yes yes
443-325 Windstream ELLICOTTCY – yes yes
443-326 AT&T BALTIMORE 2001-02-21 – yes
443-327 Windstream ABERDEEN – yes yes
443-328 Windstream SYKESVILLE – yes yes
443-329 Lumen WATERLO236 – yes yes
443-330 Windstream COCKEYSVL – yes yes
443-331 Windstream TANEYTOWN – yes yes
443-332 Windstream CROFTON 2001-05-09 yes yes
443-333 AT&T ANNAPOLIS 2009-02-13 yes yes
443-334 Verizon PIKESVILLE 2001-03-14 yes yes
443-335 T-Mobile BRYNPKLNCM – yes yes
443-336 T-Mobile ANNAPOLIS – yes yes
443-337 CORE COMMUNICATIONS, INC.- MD SPARROWSPT – yes yes
443-338 Windstream SPARKSGLNC – yes yes
443-339 Windstream SHERWD FOR – yes yes
443-340 Verizon WESTMINSTR – – yes
443-341 Lumen CATONSVL – yes yes
443-342 Windstream SOLOMONS – yes yes
443-343 AT&T MILLERSVL – yes yes
443-344 CORE COMMUNICATIONS, INC.- MD SEVERNA PK – – yes
443-345 Lumen ABERDEEN – yes yes
443-346 CORE COMMUNICATIONS, INC.- MD SEVERNA PK – yes yes
443-347 Windstream CARDIFF – yes yes
443-348 AT&T WOODLAWN – yes yes
443-349 CORE COMMUNICATIONS, INC.- MD SILVER RUN – – yes
443-350 Verizon ELKTON – yes yes
443-351 Windstream ODENTON – yes yes
443-352 Lumen PIKESVILLE – yes yes
443-353 Verizon COCKEYSVL 2004-03-19 yes yes
443-354 Lumen GLENBURNIE – yes yes
443-355 Lumen ELLICOTTCY – yes yes
443-356 Lumen BEL AIR – yes yes
443-357 Verizon PIKESVILLE – yes yes
443-358 YMAX COMMUNICATIONS CORP. - MD SALISBURY 2011-02-17 yes yes
443-359 Verizon DELMAR – yes yes
443-360 AT&T ABERDEEN – yes yes
443-361 CORE COMMUNICATIONS, INC.- MD SYKESVILLE – – yes
443-362 T-Mobile EASTON – yes yes
443-363 CORE COMMUNICATIONS, INC.- MD SEVERN – yes yes
443-364 AT&T ELLICOTTCY – yes yes
443-365 T-Mobile SALISBURY – yes yes
443-366 T-Mobile SALISBURY 2001-04-17 yes yes
443-367 Verizon COLUMBIA – yes yes
443-368 CORE COMMUNICATIONS, INC.- MD WESTMINSTR – – yes
443-369 CORE COMMUNICATIONS, INC.- MD BEL AIR – – yes
443-370 AT&T ANNAPOLIS – yes yes
443-371 Lumen BEL AIR – yes yes
443-372 Windstream EDGEWOOD 2001-03-19 yes yes
443-373 T-Mobile OCEAN CITY – yes yes
443-374 Windstream ABERDEEN – yes yes
443-375 T-Mobile HAMPSTEAD – yes yes
443-376 AT&T DUNDALK – yes yes
443-377 Verizon TOWSON 2010-06-09 yes yes
443-378 T-Mobile BALTIMORE 2004-07-27 yes yes
443-379 Comcast PIKESVILLE 2007-02-23 yes yes
443-380 Lumen WOODLAWN – yes yes
443-381 AT&T REISTERSTN – yes yes
443-382 CORE COMMUNICATIONS, INC.- MD CAMBRIDGE – – yes
443-383 Windstream SILVER RUN – yes yes
443-384 Windstream PARKVILLE – yes yes
443-385 CORE COMMUNICATIONS, INC.- MD EASTON – – yes
443-386 Verizon BALTIMORE – yes yes
443-387 CORE COMMUNICATIONS, INC.- MD POCOMOKE – – yes
443-388 Verizon BALTIMORE 2006-04-13 yes yes
443-389 CORE COMMUNICATIONS, INC.- MD SALISBURY – – yes
443-390 Bandwidth CHURCHVL – yes yes
443-391 Lumen COCKEYSVL – yes yes
443-392 AT&T BALTIMORE – yes yes
443-393 Lumen COLUMBIA – yes yes
443-394 Verizon PIKESVILLE – – yes
443-395 Verizon ABERDEEN 2009-08-13 yes yes
443-396 Lumen ODENTON – yes yes
443-397 Verizon SALISBURY 2009-04-06 yes yes
443-398 T-Mobile SYKESVILLE 2001-03-15 yes yes
443-399 Onvoy DUNDALK – yes yes
443-400 Verizon BRYNPKLNCM – yes yes
443-401 Verizon BALTIMORE 2011-10-17 yes yes
443-402 AT&T EDGEWOOD – yes yes
443-403 Lumen ABERDEEN 2001-06-20 yes yes
443-404 T-Mobile SOLOMONS – yes yes
443-405 Comcast RANDALLSTN – yes yes
443-406 AT&T ELKTON – yes yes
443-407 Verizon DUNDALK – yes yes
443-408 Verizon SPARROWSPT – yes yes
443-409 Windstream EDGEWOOD – yes yes
443-410 Lumen GLENBURNIE 2013-06-21 yes yes
443-412 AT&T CHURCHVL – yes yes
443-413 T-Mobile BALTIMORE – yes yes
443-414 T-Mobile BALTIMORE – yes yes
443-415 T-Mobile BALTIMORE – yes yes
443-416 T-Mobile BALTIMORE – yes yes
443-417 AT&T FALLSTON – yes yes
443-418 T-Mobile BALTIMORE – yes yes
443-419 Windstream GLENWOOD – yes yes
443-420 Bandwidth ELLICOTTCY – yes yes
443-421 AT&T FORK – – yes
443-422 AT&T GLENBURNIE 2009-02-13 yes yes
443-423 Lumen BALTIMORE – yes yes
443-424 AT&T CARDIFF – yes yes
443-425 AT&T PARKVILLE – yes yes
443-426 Windstream RANDALLSTN – yes yes
443-427 CORE COMMUNICATIONS, INC.- MD PRINCEANNE – – yes
443-428 CORE COMMUNICATIONS, INC.- MD COCKEYSVL – – yes
443-429 Windstream WOODLAWN – yes yes
443-430 Verizon COLUMBIA 2001-05-18 yes yes
443-431 CORE COMMUNICATIONS, INC.- MD RANDALLSTN – yes yes
443-432 Windstream PRINCEFRCK – yes yes
443-433 Verizon ANNAPOLIS 2001-02-21 yes yes
443-434 Telnyx FEDERALSBG – yes yes
443-435 T-Mobile BALTIMORE 2011-02-01 yes yes
443-436 Verizon WOODLAWN – yes yes
443-437 AT&T POCOMOKE 2004-11-01 yes yes
443-438 Verizon BALTIMORE 2008-10-08 yes yes
443-439 Verizon TRAPPE 2004-11-01 yes yes
443-440 Verizon ANNAPOLIS – yes yes
443-441 AT&T GLENWOOD – yes yes
443-442 Windstream PARKVILLE 2001-05-09 yes yes
443-443 COMMIO, LLC ARBUTUS 2023-11-21 yes yes
443-444 Verizon BALTIMORE – yes yes
443-445 Verizon ELKRIDGE – yes yes
443-446 Verizon QUEENSTOWN 2004-11-01 yes yes
443-447 AT&T BALTIMORE 2008-12-15 yes yes
443-448 Comcast DENTON 2004-11-01 yes yes
443-449 Windstream BALTIMORE 2007-03-28 yes yes
443-450 Lumen PIKESVILLE – yes yes
443-451 Windstream BALTIMORE – – yes
443-452 Windstream BALTIMORE 2005-09-07 yes yes
443-453 Onvoy BALTIMORE 2007-10-12 yes yes
443-454 T-Mobile ANNAPOLIS – yes yes
443-455 Verizon BALTIMORE 2006-03-09 yes yes
443-456 Comcast EDGEWOOD – yes yes
443-457 AT&T BRYNPKLNCM – yes yes
443-458 Verizon ANNAPOLIS – yes yes
443-459 Windstream ELKRIDGE – yes yes
443-460 Verizon ESSEX – yes yes
443-461 Windstream PARKVILLE – yes yes
443-462 Verizon BALTIMORE 2008-11-06 yes yes
443-463 T-Mobile BALTIMORE – yes yes
443-464 Windstream CHURCHVL 2010-03-16 yes yes
443-465 Verizon TOWSON – yes yes
443-466 T-Mobile ELKTON – yes yes
443-467 AT&T BALTIMORE 2009-03-20 yes yes
443-468 T-Mobile BALTIMORE 2007-04-04 yes yes
443-469 AT&T BALTIMORE 2009-03-20 yes yes
443-470 Windstream TOWSON 2008-04-29 yes yes
443-471 Windstream PIKESVILLE – yes yes
443-472 Lumen COLUMBIA – yes yes
443-473 T-Mobile BALTIMORE 2007-03-28 yes yes
443-474 AT&T CATONSVL – – yes
443-475 Verizon BALTIMORE 2011-06-01 yes yes
443-476 Verizon ANNAPOLIS – – yes
443-477 Verizon CAMBRIDGE 2007-01-13 yes yes
443-478 Verizon BALTIMORE 2009-03-06 yes yes
443-479 Verizon WATERLO236 – – yes
443-480 Verizon CHESTERTN – yes yes
443-481 Windstream ANNAPOLIS – yes yes
443-482 Verizon ANNAPOLIS – yes yes
443-483 Lumen CARDIFF – yes yes
443-484 Lumen EDGEWOOD – yes yes
443-485 Lumen ELKTON – yes yes
443-486 Lumen PRINCEFRCK – yes yes
443-487 Lumen WESTMINSTR – yes yes
443-488 AT&T BALTIMORE 2010-06-23 yes yes
443-489 AT&T CHASE – yes yes
443-490 Bandwidth EDGEWOOD – yes yes
443-491 Onvoy PARKTON – yes yes
443-492 Lumen ELKRIDGE – yes yes
443-493 Verizon DELMAR 2009-03-06 yes yes
443-494 Bandwidth MILLERSVL – yes yes
443-495 Bandwidth PARKVILLE – yes yes
443-496 T-Mobile EASTON – yes yes
443-497 T-Mobile SALISBURY – yes yes
443-498 Verizon CATONSVL – yes yes
443-499 Bandwidth JARRETTSVL – yes yes
443-500 AT&T BALTIMORE 2009-03-20 yes yes
443-501 Lumen PIKESVILLE – yes yes
443-502 AT&T HAVREGRACE – yes yes
443-503 Verizon DUNDALK – yes yes
443-504 Windstream FALLSTON – yes yes
443-505 Lumen ESSEX – yes yes
443-506 T-Mobile BALTIMORE – yes yes
443-507 AT&T HAMPSTEAD – yes yes
443-508 Windstream HAMPSTEAD – yes yes
443-509 Verizon BALTIMORE 2009-02-10 yes yes
443-510 Verizon ANNAPOLIS 2007-12-04 yes yes
443-512 Verizon EDGEWOOD – yes yes
443-513 AT&T BERLIN – yes yes
443-514 Windstream CATONSVL – yes yes
443-515 Verizon CAMBRIDGE 2009-06-08 yes yes
443-516 Onvoy SYKESVILLE – yes yes
443-517 Lumen GLENBURNIE – yes yes
443-518 Verizon COLUMBIA 2008-12-16 yes yes
443-519 Lumen TOWSON – yes yes
443-520 AT&T CATONSVL – – yes
443-521 Verizon CAMBRIDGE – yes yes
443-522 Windstream REISTERSTN – yes yes
443-523 Verizon SALISBURY – yes yes
443-524 Verizon BALTIMORE – – yes
443-525 AT&T BALTIMORE 2009-03-20 yes yes
443-526 Windstream HAVREGRACE – yes yes
443-527 T-Mobile BALTIMORE 2001-03-19 – yes
443-528 T-Mobile BEL AIR – yes yes
443-529 T-Mobile BALTIMORE 2008-07-22 yes yes
443-530 Windstream DUNDALK – yes yes
443-531 AT&T BALTIMORE 2009-03-20 yes yes
443-532 T-Mobile PRINCEFRCK – yes yes
443-533 AT&T JARRETTSVL – yes yes
443-534 Verizon ANNAPOLIS 2001-01-15 yes yes
443-535 Verizon COLUMBIA – yes yes
443-536 T-Mobile WESTMINSTR – yes yes
443-537 Verizon COLUMBIA – yes yes
443-538 T-Mobile COLUMBIA 2001-06-20 – yes
443-539 Windstream COLUMBIA – yes yes
443-540 AT&T BALTIMORE – – yes
443-541 Windstream COCKEYSVL – yes yes
443-542 Comcast COLUMBIA – yes yes
443-543 Verizon ARBUTUS – yes yes
443-544 Windstream PIKESVILLE 2001-05-10 yes yes
443-545 Lumen COLUMBIA 2001-05-18 yes yes
443-546 Verizon COLUMBIA – yes yes
443-547 Verizon WESTMINSTR 2009-05-07 yes yes
443-548 Verizon PIKESVILLE – yes yes
443-549 Windstream DUNDALK – yes yes
443-550 Lumen NORTHBEACH – yes yes
443-551 Lumen WOODLAWN – yes yes
443-552 Verizon BALTIMORE – yes yes
443-553 Verizon ELKTON – – yes
443-554 T-Mobile CHASE 2001-07-23 yes yes
443-556 Verizon COCKEYSVL – – yes
443-557 Verizon GLENBURNIE – yes yes
443-558 Verizon ABERDEEN 2001-01-15 yes yes
443-559 Comcast ESSEX – yes yes
443-560 T-Mobile BALTIMORE 2011-07-18 yes yes
443-561 Windstream ELKRIDGE – yes yes
443-562 AT&T BALTIMORE – – yes
443-563 T-Mobile BALTIMORE 2006-11-14 yes yes
443-564 Lumen TOWSON – yes yes
443-565 Windstream RANDALLSTN 2001-05-10 yes yes
443-566 Verizon CHESAPKECY 2004-09-16 yes yes
443-567 Lumen BEL AIR – yes yes
443-568 Verizon ARBUTUS – yes yes
443-569 Lumen ANNAPOLIS – yes yes
443-570 T-Mobile BALTIMORE – – yes
443-571 Verizon BALTIMORE 2011-12-06 yes yes
443-572 Verizon GLENBURNIE – yes yes
443-573 Windstream BALTIMORE – yes yes
443-574 Windstream ELLICOTTCY – yes yes
443-575 Windstream ARBUTUS 2001-05-10 yes yes
443-576 Verizon RANDALLSTN 2001-02-21 yes yes
443-577 Windstream GLENBURNIE – yes yes
443-578 XO MARYLAND, LLC COCKEYSVL – yes yes
443-579 Windstream ESSEX – yes yes
443-580 T-Mobile BALTIMORE 2011-08-25 yes yes
443-581 Onvoy CHASE – yes yes
443-582 Windstream CHURCHVL – yes yes
443-583 Windstream COLUMBIA – yes yes
443-584 Windstream CROFTON – yes yes
443-585 Windstream DARLINGTON – yes yes
443-586 CORE COMMUNICATIONS, INC.- MD DUNDALK – yes yes
443-587 Windstream EDGEWOOD – yes yes
443-588 Verizon PARKVILLE – yes yes
443-589 Windstream COCKEYSVL – yes yes
443-590 Lumen REISTERSTN – yes yes
443-591 Verizon GLENBURNIE 2009-05-07 yes yes
443-592 CORE COMMUNICATIONS, INC.- MD ELKRIDGE – yes yes
443-593 Windstream ELKTON – yes yes
443-594 Lumen SPARROWSPT – yes yes
443-595 Bandwidth SPARKSGLNC – yes yes
443-596 CORE COMMUNICATIONS, INC.- MD ESSEX – yes yes
443-597 T-Mobile SEVERNA PK – yes yes
443-598 Bandwidth SHERWD FOR – yes yes
443-599 T-Mobile SEVERN – yes yes
443-600 T-Mobile ESSEX 2001-07-23 yes yes
443-601 Windstream FALLSTON – yes yes
443-602 Verizon BALTIMORE 2007-02-15 yes yes
443-603 Windstream ANNAPOLIS – yes yes
443-604 Verizon BALTIMORE – – yes
443-605 Windstream WESTMINSTR – yes yes
443-606 Windstream FORK – yes yes
443-607 Windstream WEST RIVER – yes yes
443-608 AT&T TOWSON 2009-02-27 yes yes
443-609 Windstream SYKESVILLE – yes yes
443-610 Verizon BALTIMORE – yes yes
443-612 Verizon CATONSVL – – yes
443-613 AT&T TOWSON 2009-02-27 yes yes
443-614 Verizon SALISBURY 2001-07-23 – yes
443-615 Verizon BALTIMORE 2007-05-10 yes yes
443-616 Windstream BEL AIR – yes yes
443-617 Verizon FALLSTON 2005-04-11 yes yes
443-618 Verizon GLENBURNIE – yes yes
443-619 Verizon BEL AIR 2009-06-05 yes yes
443-620 AT&T WATERLO238 – yes yes
443-621 T-Mobile BALTIMORE – yes yes
443-622 T-Mobile BALTIMORE – yes yes
443-623 T-Mobile GLENBURNIE 2002-08-20 yes yes
443-624 Verizon PRINCEFRCK 2002-03-06 yes yes
443-625 Lumen FORK 2001-02-21 yes yes
443-626 Windstream CHASE 2001-05-10 yes yes
443-627 Lumen BALTIMORE – yes yes
443-628 CORE COMMUNICATIONS, INC.- MD GLENBURNIE – yes yes
443-629 T-Mobile BALTIMORE – yes yes
443-630 Verizon BALTIMORE 2008-05-08 yes yes
443-631 AT&T CATONSVL 2005-08-16 yes yes
443-632 Windstream TOWSON – yes yes
443-633 T-Mobile BALTIMORE 2011-07-18 yes yes
443-634 Verizon WATERLO236 2011-11-09 yes yes
443-635 AT&T BALTIMORE 2009-10-14 yes yes
443-636 T-Mobile CATONSVL – yes yes
443-637 Verizon ARGRGBSNIS 2001-02-21 yes yes
443-638 GLOBAL NAPS SOUTH, INC. - MD ELLICOTTCY – – yes
443-639 Windstream HAMPSTEAD – yes yes
443-640 Windstream BEL AIR 2001-05-18 yes yes
443-641 Lumen PIKESVILLE 2001-05-18 yes yes
443-642 Verizon BALTIMORE 2006-11-08 yes yes
443-643 Verizon BEL AIR – yes yes
443-644 Windstream JARRETTSVL – yes yes
443-645 Windstream MILLERSVL – yes yes
443-646 Windstream NORTHBEACH – yes yes
443-647 Windstream NEWWINDSOR – yes yes
443-648 AT&T ESSEX – yes yes
443-649 Windstream SPARROWSPT 2001-06-20 yes yes
443-650 Verizon REISTERSTN 2001-02-20 yes yes
443-651 Verizon BALTIMORE 2011-07-08 yes yes
443-652 T-Mobile TOWSON – yes yes
443-653 T-Mobile PARKVILLE 2001-05-18 yes yes
443-654 Verizon WATERLO236 2008-08-28 yes yes
443-655 AT&T BEL AIR – yes yes
443-656 Windstream COLUMBIA 2001-05-10 yes yes
443-657 Lumen RANDALLSTN – yes yes
443-658 Onvoy WOODLAWN – – yes
443-659 Onvoy WEST RIVER – – yes
443-660 Comcast PIKESVILLE – yes yes
443-661 Windstream WATERLO238 – yes yes
443-662 Windstream SPARKSGLNC 2001-05-10 yes yes
443-663 Verizon WOODLAWN – yes yes
443-664 Windstream OCEAN CITY – yes yes
443-665 CORE COMMUNICATIONS, INC.- MD NANTICOKE – yes yes
443-666 Lumen CHESTERTN 2012-05-23 yes yes
443-667 Verizon DELMAR 2023-05-16 yes yes
443-668 AT&T CATONSVL 2001-01-15 yes yes
443-669 Windstream DELMAR – yes yes
443-670 Windstream CATONSVL 2001-05-10 yes yes
443-671 AT&T NEWWINDSOR – yes yes
443-672 AT&T PARKTON – yes yes
443-673 Windstream BRYNPKLNCM 2001-05-10 yes yes
443-674 AT&T NORTH EAST – yes yes
443-675 Windstream RANDALLSTN – yes yes
443-676 AT&T BALTIMORE 2001-06-20 – yes
443-677 T-Mobile BALTIMORE 2001-03-15 yes yes
443-678 Verizon PARKVILLE – yes yes
443-679 AT&T SEVERN – yes yes
443-680 T-Mobile BALTIMORE 2010-09-27 yes yes
443-681 Verizon BALTIMORE 2009-06-05 yes yes
443-682 Verizon BALTIMORE 2006-12-19 yes yes
443-683 Verizon BALTIMORE 2007-04-09 yes yes
443-684 Verizon PRINCEFRCK 2008-10-08 yes yes
443-685 Windstream SEVERN – yes yes
443-686 Verizon FALLSTON – yes yes
443-687 Verizon BALTIMORE 2009-09-08 yes yes
443-688 Windstream SEVERN 2001-05-10 yes yes
443-689 Windstream COCKEYSVL 2001-05-10 yes yes
443-690 Verizon BALTIMORE – – yes
443-691 AT&T BALTIMORE 2001-01-15 – yes
443-692 Verizon BALTIMORE – yes yes
443-693 AT&T PERRYVILLE – yes yes
443-694 T-Mobile SEVERNA PK 2001-04-20 yes yes
443-695 Verizon BALTIMORE – – yes
443-696 Windstream DUNDALK 2001-05-10 yes yes
443-697 GLOBAL NAPS SOUTH, INC. - MD CATONSVL – – yes
443-698 AT&T ODENTON – yes yes
443-699 Verizon ANNAPOLIS 2011-08-10 yes yes
443-701 Verizon ARBUTUS – yes yes
443-702 Windstream ARGRGBSNIS 2001-05-10 yes yes
443-703 Verizon BALTIMORE – yes yes
443-704 Windstream ODENTON 2001-05-10 yes yes
443-705 Verizon COCKEYSVL – yes yes
443-706 Windstream CRISFIELD – yes yes
443-707 T-Mobile ABERDEEN – yes yes
443-708 Lumen BALTIMORE – yes yes
443-709 Windstream ARBUTUS – yes yes
443-710 Verizon CATONSVL – yes yes
443-712 Windstream REISTERSTN – yes yes
443-713 Peerless GLENBURNIE 2012-09-19 yes yes
443-714 AT&T ANNAPOLIS – yes yes
443-715 Windstream NORTH EAST – yes yes
443-716 Windstream ANNAPOLIS – yes yes
443-717 Verizon BALTIMORE 2005-09-14 yes yes
443-718 Windstream COLUMBIA 2008-03-05 yes yes
443-719 Windstream JARRETTSVL – yes yes
443-720 Verizon ABERDEEN 2012-11-27 yes yes
443-721 Verizon BALTIMORE 2009-07-06 yes yes
443-722 T-Mobile BALTIMORE 2001-03-09 – yes
443-723 T-Mobile BALTIMORE 2011-10-06 yes yes
443-724 Windstream EASTON – yes yes
443-725 Windstream PARKVILLE – yes yes
443-726 T-Mobile BALTIMORE 2011-10-06 yes yes
443-727 Windstream BISHOPVL – yes yes
443-728 Windstream BERLIN – yes yes
443-729 Windstream WOODLAWN – yes yes
443-730 Windstream ESSEX – yes yes
443-731 AT&T PT DEPOSIT – yes yes
443-732 AT&T SILVER RUN – yes yes
443-733 AT&T WATERLO238 – yes yes
443-734 Verizon SEVERN – yes yes
443-735 AT&T SALISBURY – – yes
443-736 AT&T SALISBURY – yes yes
443-737 Windstream WATERLO238 – yes yes
443-738 Windstream PIKESVILLE – yes yes
443-739 T-Mobile BALTIMORE 2001-07-23 – yes
443-740 Lumen BALTIMORE 2005-02-03 yes yes
443-741 Verizon COLUMBIA 2011-03-29 yes yes
443-742 AT&T BALTIMORE – – yes
443-743 Verizon BALTIMORE 2008-04-07 yes yes
443-744 T-Mobile REISTERSTN 2002-07-02 yes yes
443-745 Verizon COLUMBIA – – yes
443-746 Lumen EASTON 2002-02-22 yes yes
443-747 CORE COMMUNICATIONS, INC.- MD PT DEPOSIT 2002-02-22 yes yes
443-748 Windstream MILLERSVL 2001-05-11 yes yes
443-749 Windstream GLENBURNIE – yes yes
443-750 Verizon BALTIMORE 2010-06-08 yes yes
443-751 Windstream WOODLAWN 2001-05-11 yes yes
443-752 Verizon BEL AIR 2001-10-17 yes yes
443-753 Verizon WATERLO236 – yes yes
443-754 Verizon SALISBURY 2010-06-09 yes yes
443-755 Verizon WATERLO238 – yes yes
443-756 AT&T BALTIMORE – – yes
443-757 Windstream ELKRIDGE 2001-05-11 yes yes
443-758 Verizon ANNAPOLIS – yes yes
443-759 Verizon BALTIMORE 2007-10-29 yes yes
443-760 AT&T ABERDEEN – yes yes
443-761 T-Mobile TOWSON 2008-05-28 yes yes
443-762 T-Mobile BALTIMORE 2001-01-10 yes yes
443-763 T-Mobile GLENBURNIE – yes yes
443-764 T-Mobile GLENBURNIE 2008-08-21 yes yes
443-765 AT&T CATONSVL 2001-07-23 yes yes
443-766 Windstream COLUMBIA 2005-05-18 yes yes
443-767 Windstream WORTHINGTN 2001-05-11 yes yes
443-768 T-Mobile BALTIMORE 2001-05-18 yes yes
443-769 T-Mobile BALTIMORE 2008-09-16 yes yes
443-770 Verizon ARGRGBSNIS – yes yes
443-771 Verizon PRINCEFRCK 2010-09-08 yes yes
443-772 Windstream ESSEX 2001-07-23 yes yes
443-773 Verizon BRYNPKLNCM – yes yes
443-774 AT&T COLUMBIA 2018-11-19 yes yes
443-775 Verizon ANNAPOLIS 2014-10-08 yes yes
443-776 Bandwidth ELKRIDGE 2014-01-17 yes yes
443-777 Verizon ESSEX – yes yes
443-778 Verizon WATERLO236 – yes yes
443-779 Verizon ABERDEEN – yes yes
443-780 Windstream WOODLAWN 2001-07-23 yes yes
443-781 Onvoy ARGRGBSNIS – yes yes
443-782 Verizon ANNAPOLIS – yes yes
443-783 Verizon SALISBURY – – yes
443-784 AT&T ARGRGBSNIS – yes yes
443-785 Onvoy ARBUTUS – – yes
443-786 Verizon EASTON – yes yes
443-787 Windstream BEL AIR – yes yes
443-788 T-Mobile ABERDEEN – yes yes
443-789 AT&T WESTMINSTR – yes yes
443-790 T-Mobile GLENBURNIE 2001-11-19 yes yes
443-791 AT&T TOWSON – yes yes
443-792 Verizon BRYNPKLNCM 2007-10-18 yes yes
443-793 Verizon PARKVILLE – yes yes
443-794 AT&T BALTIMORE – – yes
443-795 Verizon SEVERN – yes yes
443-796 Verizon PIKESVILLE – yes yes
443-797 Verizon TOWSON – yes yes
443-798 Lumen TOWSON – yes yes
443-799 AT&T BALTIMORE 2001-07-23 – yes
443-800 T-Mobile BALTIMORE 2011-01-31 yes yes
443-801 T-Mobile BALTIMORE – yes yes
443-802 T-Mobile BALTIMORE – yes yes
443-803 T-Mobile BALTIMORE – yes yes
443-804 T-Mobile BALTIMORE – yes yes
443-805 T-Mobile GLENBURNIE 2008-07-24 yes yes
443-806 T-Mobile BALTIMORE 2006-03-08 yes yes
443-807 T-Mobile FALLSTON – yes yes
443-808 Bandwidth ANNAPOLIS 2014-04-04 yes yes
443-809 Lumen TOWSON 2014-06-13 yes yes
443-810 T-Mobile BALTIMORE 2008-09-04 yes yes
443-812 Verizon COLUMBIA 2001-01-15 yes yes
443-813 Verizon BALTIMORE 2007-09-14 yes yes
443-814 Verizon BALTIMORE 2010-06-15 yes yes
443-815 Verizon ESSEX – yes yes
443-816 Verizon SEVERNA PK – yes yes
443-817 Verizon ARGRGBSNIS – yes yes
443-818 Lumen ARGRGBSNIS 2005-12-30 yes yes
443-819 T-Mobile BEL AIR 2015-01-21 yes yes
443-820 Windstream ELKRIDGE – yes yes
443-821 T-Mobile WESTMINSTR 2010-07-13 yes yes
443-822 T-Mobile ANNAPOLIS – yes yes
443-823 Verizon TOWSON 2006-07-13 yes yes
443-824 T-Mobile TOWSON 2001-05-18 yes yes
443-825 T-Mobile BALTIMORE 2006-11-29 yes yes
443-826 Verizon BALTIMORE 2010-06-25 yes yes
443-827 Verizon BALTIMORE – yes yes
443-828 Windstream ELLICOTTCY 2001-05-11 yes yes
443-829 T-Mobile BALTIMORE – yes yes
443-830 Windstream CATONSVL 2001-08-21 yes yes
443-831 AT&T BALTIMORE – – yes
443-832 Lumen COLUMBIA – yes yes
443-833 Windstream ARBUTUS – yes yes
443-834 Verizon TOWSON – yes yes
443-835 Verizon BALTIMORE 2008-12-11 yes yes
443-836 Verizon BALTIMORE 2013-01-21 yes yes
443-837 Windstream ANNAPOLIS 2001-09-24 yes yes
443-838 AT&T BALTIMORE – – yes
443-839 T-Mobile BALTIMORE 2006-04-17 yes yes
443-840 AT&T CATONSVL 2005-05-04 yes yes
443-841 Verizon TOWSON – yes yes
443-842 Verizon BALTIMORE 2011-03-10 yes yes
443-843 Verizon HAVREGRACE – yes yes
443-844 Verizon BALTIMORE 2006-02-13 yes yes
443-845 Verizon BALTIMORE – yes yes
443-846 AT&T TOWSON – yes yes
443-847 Verizon TOWSON 2006-10-12 yes yes
443-848 T-Mobile GLENBURNIE – yes yes
443-849 Verizon TOWSON 2001-05-18 – yes
443-850 T-Mobile BALTIMORE 2001-09-24 – yes
443-851 T-Mobile CATONSVL 2001-08-21 yes yes
443-852 AT&T ANNAPOLIS 2001-08-21 yes yes
443-853 Verizon BALTIMORE 2010-07-27 yes yes
443-854 T-Mobile BALTIMORE 2001-11-19 – yes
443-855 Windstream ABERDEEN 2005-05-20 yes yes
443-856 CORE COMMUNICATIONS, INC.- MD OCEAN CITY 2002-07-02 yes yes
443-857 T-Mobile BALTIMORE – – yes
443-858 T-Mobile BALTIMORE – – yes
443-859 T-Mobile SALISBURY – yes yes
443-860 AT&T CATONSVL 2005-05-04 yes yes
443-861 Verizon ABERDEEN 2009-08-13 yes yes
443-862 Verizon TOWSON 2011-10-07 yes yes
443-863 Verizon BALTIMORE 2010-08-09 yes yes
443-864 T-Mobile COLUMBIA 2001-12-19 yes yes
443-865 T-Mobile BALTIMORE 2002-04-19 yes yes
443-866 T-Mobile BEL AIR 2002-07-02 yes yes
443-867 Windstream GLENBURNIE – yes yes
443-868 Verizon ESSEX – yes yes
443-869 Verizon BALTIMORE 2006-06-12 yes yes
443-870 Lumen PIKESVILLE – yes yes
443-871 T-Mobile ANNAPOLIS – yes yes
443-872 Windstream BALTIMORE – yes yes
443-873 Onvoy BALTIMORE 2010-02-23 yes yes
443-874 Windstream BALTIMORE – yes yes
443-875 AT&T ANNAPOLIS – yes yes
443-876 T-Mobile BEL AIR – yes yes
443-877 Lumen NORTH EAST – yes yes
443-878 Verizon COLUMBIA – yes yes
443-879 Verizon DUNDALK – yes yes
443-880 AT&T SALISBURY – yes yes
443-881 T-Mobile REISTERSTN – yes yes
443-882 T-Mobile BALTIMORE 2011-02-01 yes yes
443-883 AT&T GLENBURNIE – yes yes
443-884 Windstream BALTIMORE – yes yes
443-885 Verizon BALTIMORE – yes yes
443-886 AT&T COCKEYSVL – yes yes
443-887 Windstream CATONSVL 2010-05-05 yes yes
443-888 Windstream PRINCEANNE 2011-01-06 yes yes
443-889 T-Mobile GLENBURNIE 2001-04-20 yes yes
443-890 Verizon BALTIMORE 2011-08-10 yes yes
443-891 Verizon GLENBURNIE – yes yes
443-892 Bandwidth NEWWINDSOR 2011-08-11 yes yes
443-893 Verizon WOODLAWN – yes yes
443-894 T-Mobile BALTIMORE 2011-06-30 yes yes
443-895 Verizon TOWSON 2007-04-09 yes yes
443-896 AT&T COLUMBIA – yes yes
443-897 AT&T BALTIMORE 2011-04-12 yes yes
443-898 Lumen PIKESVILLE 2005-12-08 yes yes
443-899 Lumen WATERLO238 – yes yes
443-900 Verizon TOWSON 2012-05-23 yes yes
443-901 Windstream TOWSON 2001-08-21 yes yes
443-902 Verizon BALTIMORE 2011-01-06 yes yes
443-903 Verizon BEL AIR 2011-09-07 yes yes
443-904 Verizon BALTIMORE 2001-10-17 yes yes
443-905 AT&T ANNAPOLIS – yes yes
443-906 Peerless SEVERNA PK 2012-09-20 yes yes
443-907 Verizon ELKTON 2001-04-20 yes yes
443-908 Verizon BALTIMORE 2011-06-29 yes yes
443-909 Verizon BALTIMORE 2006-08-09 yes yes
443-910 AT&T BEL AIR 2001-04-20 yes yes
443-912 CORE COMMUNICATIONS, INC.- MD TOWSON 2002-07-02 yes yes
443-913 T-Mobile BALTIMORE 2011-06-30 yes yes
443-914 AT&T WORTHINGTN – yes yes
443-915 Verizon BALTIMORE 2011-09-07 yes yes
443-916 T-Mobile BALTIMORE 2011-08-22 yes yes
443-917 Onvoy COLUMBIA 2011-10-07 yes yes
443-918 AT&T TANEYTOWN – yes yes
443-919 Windstream BALTIMORE – – yes
443-920 AT&T SYKESVILLE – yes yes
443-921 Windstream TOWSON – yes yes
443-922 Windstream EDGEWOOD 2006-02-07 yes yes
443-923 Windstream BALTIMORE 2001-05-11 – yes
443-924 Verizon ANNAPOLIS 2009-07-06 yes yes
443-925 T-Mobile BALTIMORE 2006-02-24 yes yes
443-926 Lumen ANNAPOLIS – yes yes
443-927 Lumen BALTIMORE – yes yes
443-928 Verizon BALTIMORE 2001-09-24 yes yes
443-929 T-Mobile PIKESVILLE 2001-04-20 yes yes
443-930 Verizon BALTIMORE 2011-04-06 yes yes
443-931 Verizon BALTIMORE 2011-10-24 yes yes
443-932 T-Mobile BALTIMORE 2011-08-22 yes yes
443-933 AT&T COCKEYSVL 2004-04-20 yes yes
443-934 Verizon BALTIMORE 2007-12-04 yes yes
443-935 AT&T TOWSON 2006-07-31 yes yes
443-936 AT&T ELKRIDGE 2017-02-23 yes yes
443-937 AT&T UNION BDG – yes yes
443-938 Verizon BALTIMORE 2007-08-06 yes yes
443-939 T-Mobile BALTIMORE 2002-09-23 yes yes
443-940 Windstream PIKESVILLE 2001-08-21 yes yes
443-941 AT&T ELKTON 2011-09-07 yes yes
443-942 AT&T SEVERNA PK – yes yes
443-943 AT&T SPARROWSPT – yes yes
443-944 Comcast SALISBURY 2006-06-08 yes yes
443-945 AT&T ELKTON 2002-07-02 yes yes
443-946 CORE COMMUNICATIONS, INC.- MD PARKVILLE – yes yes
443-947 Windstream PERRYVILLE – yes yes
443-948 T-Mobile BALTIMORE 2011-08-22 yes yes
443-949 Comcast ANNAPOLIS 2006-06-28 yes yes
443-951 Lumen ANNAPOLIS – yes yes
443-952 Verizon WESTMINSTR 2011-09-07 yes yes
443-953 Verizon SALISBURY 2011-09-07 yes yes
443-954 Windstream BALTIMORE 2005-07-06 yes yes
443-955 Verizon BALTIMORE 2006-03-13 yes yes
443-956 AT&T BALTIMORE – – yes
443-957 AT&T BALTIMORE – yes yes
443-960 Verizon GLENBURNIE 2011-10-07 yes yes
443-961 INTRADO COMMUNICATIONS, LLC BALTIMORE 2014-12-23 yes yes
443-962 Verizon GLENBURNIE 2007-09-14 yes yes
443-963 Bandwidth BALTIMORE – yes yes
443-964 Lumen NORTHBEACH 2006-05-12 yes yes
443-965 T-Mobile BALTIMORE 2006-06-21 yes yes
443-966 Verizon FALLSTON 2006-09-13 yes yes
443-967 Verizon NORTH EAST 2001-04-20 yes yes
443-968 AT&T PRINCEFRCK – yes yes
443-969 Windstream ESSEX 2001-05-11 yes yes
443-970 Verizon BALTIMORE 2011-11-21 yes yes
443-971 Bandwidth TANEYTOWN 2011-02-16 yes yes
443-972 Windstream CAMBRIDGE 2011-11-21 yes yes
443-973 Verizon ELLICOTTCY – yes yes
443-974 AT&T WESTMINSTR – yes yes
443-975 AT&T PRINCEFRCK – yes yes
443-977 Verizon BALTIMORE 2006-10-12 yes yes
443-978 Verizon SALISBURY 2011-11-21 yes yes
443-979 Verizon COLUMBIA 2011-11-21 yes yes
443-980 AT&T CATONSVL – yes yes
443-981 Verizon FALLSTON 2011-11-21 yes yes
443-982 YMAX COMMUNICATIONS CORP. - MD BALTIMORE 2007-05-30 yes yes
443-983 T-Mobile BALTIMORE 2002-07-02 yes yes
443-984 Verizon BALTIMORE – – yes
443-985 T-Mobile RANDALLSTN 2001-06-20 yes yes
443-986 Verizon BALTIMORE 2006-07-13 yes yes
443-987 Verizon BEL AIR – yes yes
443-988 Lumen CENTREVL 2006-06-08 yes yes
443-989 Windstream GLENBURNIE 2001-05-11 yes yes
443-990 Bandwidth BALTIMORE 2011-02-04 yes yes
443-991 Verizon TOWSON 2011-12-01 yes yes
443-992 Lumen BALTIMORE – yes yes
443-993 T-Mobile ELKTON 2010-12-13 yes yes
443-994 AT&T ANNAPOLIS – – yes
443-995 AT&T ANNAPOLIS – – yes
443-996 AT&T CATONSVL – – yes
443-997 Verizon BALTIMORE – – yes
443-998 Verizon PARKVILLE 2001-03-19 yes yes

Frequently asked

How many prefixes does area code 443 have?

785 NXX blocks are assigned of 786 possible. Each block is 10,000 consecutive numbers, so the code currently covers about 7,850 thousand-number ranges across 81 rate centers.

What do the first three digits after 443 tell me?

They identify the block, which tells you the rate center it was allocated to and the carrier that received it. They do not tell you who serves the number today: portability moves numbers between carriers, and pooling splits a block between several of them.

Is a 443 prefix tied to a specific town?

To a rate center, which is billing geography rather than a town. NANPA abbreviates rate center names to ten characters and in large metros uses zone codes, so the name is a NANPA label, not a place name.

What does “pooled” mean in the 443 table?

That the block is in thousands-block pooling: carriers draw 1,000-number lots from it instead of taking all 10,000. 701 of 443's blocks are pooled, which is how regulators slowed down area code exhaustion – and why one prefix can belong to several carriers.

Source and limits

NANPA CO Code Assignment Records, all states, utilized codes, file updated 11/01/2026 – the rows where the record's Use field is “AS” (assigned). Unavailable codes are excluded. The records say who received a block and when, not who serves a particular number today.

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