Rate Centre Lookup

21,763 rate centres across the United States and Canada. A rate centre is the telephone exchange area a number is homed to — the thing that decides which area codes can serve an address, and whether a call between two points is local.

Rate centre	Region	Area codes	Incumbent	LATA	LIR	Blocks	Switches
Pleasant Hill	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	CLOVIS
Portales	NM	575	QWEST CORPORATION (9636)	664	—	66	ALBQNM10KMD, ALBQNMMAX2Y, ALBQNMMAX4Y +9
Pueblo Pintado	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	1	PUEBLO PINTADO
Quemado	NM	575	WESTERN NEW MEXICO TEL. CO., INC. (2268)	664	—	2	ALBQNMMAXQX, QUEMADO
Questa	NM	575	QWEST CORPORATION (9636)	664	—	25	ALBQNM10KMD, ALBQNMMAX2Y, ALBQNMMAX4Y +5
Ragland	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	CLOVIS
Ramah	NM	505	CENTURYTEL SOUTHWEST INC-NM DBA CENTURYLINK - NM (2274)	664	—	19	ALBQNM10X2X, ALBQNMMAX4Y, ALBQNMMAX7Y +3
Ranchvale	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	CLOVIS
Raton	NM	575	QWEST CORPORATION (9636)	664	—	46	ALBQNM10KMD, ALBQNMMAX2Y, ALBQNMMAX4Y +9
Red River	NM	575	QWEST CORPORATION (9636)	664	—	25	ALBQNM10KMD, ALBQNM10X3X, ALBQNMMAX2Y +7
Reserve	NM	575	WESTERN NEW MEXICO TEL. CO., INC. (2268)	664	—	2	ALBQNMMAXQX, RESERVE
Roswell	NM	575	QWEST CORPORATION (9636)	664	—	199	ALBQNM10KMD, ALBQNM10LMD, ALBQNM10MMD +17
Roy	NM	575	E.N.M.R. TEL COOP (2262)	664	—	3	ALBQNMMAXLX, ROY
Ruidoso	NM	575	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	74	ALBQNM10QMD, ALBQNMMAX2Y, ALBQNMMAX4Y +11
Ruidoso Downs	NM	575	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	28	ALBQNMMAX2Y, ALBQNMMAX4Y, ALBQNMMAX7Y +7
San Jon	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	SAN JON
San Ysidro	NM	575	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	19	ALBQNM10X3X, ALBQNMMAX4Y, ALBQNMMAXLX +3
Sanostee	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	7	ALBQNMMAXLX, ALBQNMMAXSY, SANOSTEE
Santa Fe	NM	505	QWEST CORPORATION (9636)	664	—	505	ALBQNM10KMD, ALBQNM10LMD, ALBQNM10MMD +28
Santa Rosa	NM	575	E.N.M.R. TEL COOP (2262)	664	—	13	ALBQNMMAXLX, ALBQNMMAXQX, ALBQNMMAXSY +2
Santa Teresa	NM	575	QWEST CORPORATION (9636)	664	—	89	ALBQNM10KMD, ALBQNMMAX2Y, ALBQNMMAX4Y +11
Shiprock	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	13	ALBQNM10QMD, ALBQNMMAXLX, ALBQNMMAXSY +4
Silver City	NM	575	QWEST CORPORATION (9636)	664	—	120	ALBQNMMAX2Y, ALBQNMMAX4Y, ALBQNMMAX7Y +11
Socorro	NM	575	QWEST CORPORATION (9636)	664	—	63	ALBQNM10KMD, ALBQNM10X3X, ALBQNMMAX2Y +11
South Clovis	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	SOUTH CLOVIS
Springer	NM	575	QWEST CORPORATION (9636)	664	—	27	ALBQNM10KMD, ALBQNM10MMD, ALBQNM10X3X +8
Taos	NM	575	QWEST CORPORATION (9636)	664	—	122	ALBQNM10KMD, ALBQNM10X3X, ALBQNMMAX2Y +12
Tatum	NM	575	LEACO RURAL TEL. COOP., INC. (2264)	664	—	1	TATUM
Texico	NM	575	ROOSEVELT COUNTY RURAL TEL. COOP., INC. (2272)	664	—	10	ALBQNMMAXIY, ALBQNMMAY0X, ARCH
Tierra Amarilla	NM	575	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	18	ALBQNM10X3X, ALBQNMMAX4Y, ALBQNMMAXLX +3
Toadlena	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	7	ALBQNMMAXLX, ALBQNMMAXSY, TOADLENA
Tohatchi	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	11	ALBQNMMAXLX, ALBQNMMAXSY, TOHATCHI
Torreon	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	6	ALBQNMMAXQX, TORREON (SANDOVAL)
Trementina	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	CLOVIS
Truchas	NM	505	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	9	ALBQNMMAX4Y, ALBQNMMAXPY, TRUCHAS
Truth or Consequences	NM	575	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	47	ALBQNMMAX2Y, ALBQNMMAX4Y, ALBQNMMAX7Y +9
Tse Bonito	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	11	ALBQNMMAXLX, ALBQNMMAXSY, TSE BONITO
Tucumcari	NM	575	QWEST CORPORATION (9636)	664	—	55	ALBQNM10KMD, ALBQNM10X3X, ALBQNMMAX2Y +12
Tularosa	NM	575	TULAROSA BASIN TELEPHONE CO., INC. (2265)	664	—	10	ALBQNMMAX2Y, ALMGNMGM0MD, TLRSNMXC1MD +1
Twin Lakes	NM	505	NAVAJO COMM CO INC NM DBA NAVAJO COMM CO NM (4450)	664	—	7	ALBQNMMAXLX, ALBQNMMAXSY, TWIN LAKES
Vallecitos	NM	575	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	18	ALBQNMMAX4Y, ALBQNMMAXPY, VALLECITOS
Vanderwagen	NM	505	CENTURYTEL SOUTHWEST INC-NM DBA CENTURYLINK - NM (2274)	664	—	18	ALBQNM10X2X, ALBQNMMAX4Y, ALBQNMMAXKY +2
Vaughn	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	VAUGHN
Velarde	NM	505	VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1193)	664	—	11	ALBQNMMAX4Y, ALBQNMMAXPY, VELARDE
Wagon Mound	NM	575	LA JICARITA RURAL TEL. COOP., INC. (2263)	664	—	2	MORA
Weber City	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	WEBER CITY
White Lakes	NM	575	E.N.M.R. TEL COOP (2262)	664	—	1	CLOVIS
White Rock	NM	505	QWEST CORPORATION (9636)	664	—	59	ALBQNM10LMD, ALBQNMMAX2Y, ALBQNMMAX4Y +8
Zuni	NM	505	CENTURYTEL SOUTHWEST INC-NM DBA CENTURYLINK - NM (2274)	664	—	29	ALBQNM10X2X, ALBQNMMAX4Y, ALBQNMMAX7Y +4

Searching for a place, not a rate centre?

Many places are localities inside a larger rate centre and hold no numbers of their own, so they are not listed above — Clinton, Maryland is part of Washington Zone 16. The Area Codes tab resolves a place name through to whichever rate centre actually serves it.

What These Terms Mean

The fields shown on the area code, rate centre and LATA pages, in plain language.

Rate centre — The exchange area a number belongs to: The telephone exchange area a block of numbers is homed to, and what decides whether a call between two points is local. It is not a city: many places are localities inside a larger rate centre and have no numbers of their own. Clinton, Maryland is part of the Washington Zone 16 rate centre, so its numbers are 227, 240 and 301.
NPA-NXX — Area code and prefix: The first six digits of a North American number. NPA is the three-digit area code, NXX the three-digit prefix — so 416-200 is NPA 416, NXX 200. Knowing the NPA-NXX identifies the exchange a number was issued from.
Thousands-block — A prefix split into ten pieces: A prefix holds 10,000 numbers, which is more than most carriers need, so prefixes are pooled: split into ten blocks of a thousand and handed to different carriers. The block digit is the fourth digit of the number, and A means the whole prefix went to one carrier. This is why 512 has 783 prefixes but 6,011 rows — 512-555-1xxx and 512-555-2xxx can belong to different companies.
OCN — The carrier holding the block: Operating Company Number — a four-character code identifying the carrier of record for a block. Two carriers can share a brand name and still have different OCNs, which is why the tables show the number alongside the name.
ILEC — The incumbent operator for the area: Incumbent Local Exchange Carrier — the established local operator for a rate centre, usually the former Bell company. It differs from the OCN whenever a block belongs to a competitor: a Toronto block can be held by Bell Cellular while the incumbent for the rate centre is Bell Ontario.
LATA — Where a call stops being local: Local Access and Transport Area — the region a call is routed within before it becomes long-haul. The boundaries date from the 1984 Bell System breakup and still shape how calls are routed and rated. A LATA is three digits, though some rate centres are published with a two-digit sub-code appended, shown here as 460.17. Browse every LATA.
LIR — The Canadian equivalent, roughly: Local Interconnection Region — how Canadian carriers divide territory for exchanging traffic. It only applies in Canada, so this field is blank on every US record by definition rather than by omission.
Switch / CLLI — The equipment serving the block: The telephone switch a block is routed through, named by its CLLI code — an eleven-character identifier where the first characters encode the place, as in TOROON01DS0 for Toronto. A switch typed POI is a point of interconnection, where carriers hand traffic to each other rather than serve subscribers directly.
Overlay and split — The two ways to add an area code: A split divides a region and gives part of it a new code, so existing numbers change. An overlay adds a code on top of the same territory, so nobody has to change a number — but everyone has to dial ten digits, since two numbers in the same place can now differ only by area code. 786 overlaid 305 in 1998; 941 split from 813 in 1995.

One limitation worth knowing. All of this describes the block a number was issued from. Number portability means a number can be carried to another carrier while keeping its digits, so the carrier shown is the carrier of record for the block, not necessarily whoever serves that specific line today. Nothing in this data can tell you which — only a live portability lookup can.