225:
numbers. The state's telecommunications regulator, the
Illinois Commerce Commission, at the urging of consumer advocates, pushed back against industry and FCC demands for a distributed overlay for 847 from 1999 to 2001 as half of the existing 847-numbers were not in use. The Citizens Utility Board, a Chicago-based consumer group, attempted to litigate against an FCC requirement that calls within the same area code be dialed with the area code when 224 was introduced in 2002. A similar fight by New York state's Public Service Commission to maintain seven-digit dialing within the same area code (including calls within
113:
were assigned to single providers who managed the plant in each location. This allocated all ten thousand line numbers of the central office code to one provider, even when demand could not exhaust the numbering pool. A new, competitive provider for the same area would be assigned the entire number space of a new central office prefix, reducing the overall efficiency of number utilization in the area.
54:, to be shared among all providers delivering services in that rate center. Number pooling reduced the quantity of unused telephone numbers in markets which have been fragmented between multiple service providers, avoided central office prefix exhaustion in high growth areas, and extended the lifetime of the North American
488:
Ten thousand telephone numbers for a hamlet of 600 people is inefficient, but the actual result, were number pooling not available, would be seven times worse; each telephone company would be assigned an entire 10,000-number telephone exchange code for a total of 70,000 numbers. Repeating this method
112:
on local service. The landline telephone systems evolved over a period of over one hundred years before diversification, so that it was technically difficult to share infrastructure between multiple providers. Central offices were established based on local demand and convention, and dialing prefixes
49:
in the United States. The method allocates telephone numbers in blocks of 1,000 consecutive numbers of a given central office code to telephony service providers. In the United States it replaced the practice of allocating all 10,000 numbers of a central office prefix at a time. Under number pooling,
155:
provider could become a telephone company, with telephony merely being one more application running over the packet-switched network. There was no requirement that the
Internet to telephony gateway be operated by a facilities-based telco or cable company; anyone could buy a large block of telephone
304:
was abandoned in 2012. A plan which would have implemented a concentrated overlay in 2002 in the greater
Hampton Roads area, Virginia area code 757, was scrapped after number pooling was implemented, and it was not until 2022 that area code 948 was introduced as an all-services overlay area code.
311:
Thousands-block number pooling is just one of several approaches for conserving numbering resources. Other options include consolidating multiple rate centers into one–as much of the problem is caused by carriers needlessly requesting a prefix in each rate center–allowing carriers to use a single
224:
with 10-digit local calling was drawing public backlash; inefficient allocation meant that some providers had been holding 10,000 number blocks in rate centers where they had few or no clients. A carrier with a few thousand clients scattered across multiple rate centers often had 50,000 allocated
358:
In area codes where service providers are required to participate in thousands-block number pooling, the carrier is to return any blocks of 1,000 numbers which are more than 90% empty; an exemption applies for one block per rate center which the carrier must keep as an initial block or footprint
240:
number pooling trial, including a requirement that telcos actually use 60% percent of their allocations (increased to 75% after three years) before requesting more phone numbers, allocation of new numbers to phone companies in blocks of 1,000 and a requirement that phone companies return unused
255:
While mandatory number pooling requirements originally existed only in the top 100 MSA's, the
National Association of Regulatory Commissioners (NARUC) petitioned the FCC in 2006 to extend them to rural states to cope with demand for numbers for VoIP. All US states have implemented their own
194:
Telephone number pooling relies on LNP as it relies on carriers to return blocks of mostly unused numbers. The thousand-number blocks being returned to the pool may be "contaminated" with up to a hundred working numbers which must be ported to a block which the carrier intends to keep.
159:
With the advent of competition, each individual carrier required its own prefixes in each rate center, depleting available prefixes within high-growth and high-competition areas. Many of these new prefixes were sparsely used. This led to a rapid increase in the introduction of new
342:
In areas which were running short of numbers, blocks of 10,000 numbers would be assigned to an individual rate center; from there, it would be split into smaller blocks of 1,000 numbers each, for assignment to individual providers by a number pooling administrator.
287:
was delayed in 2001 as codes were reclaimed and numbers pooled; it was later reinstated, initially affecting area code 360 and expanding to the other mentioned area codes as needed, with 10-digit dialing mandatory as of
September 30, 2017. A proposed
90:, and a four-digit line number. Thus, each central office provides a resource of 10,000 telephone lines with a unique number each. While often enough for small communities, most cities require multiple central offices to service the community.
333:
structure. A block of 1,000 numbers per carrier, like the earlier allocation of 10,000 numbers per carrier in each rate center, is arbitrary. Local number portability permits telephone numbers to be assigned to carriers one at a time.
354:
Thousands-block number pooling is a process by which the 10,000 numbers in a central office code (NXX) are separated into ten sequential blocks of 1,000 numbers each (thousands-blocks), and allocated separately within a rate
320:
to port existing numbers from all rate centers in that area, or even placing all the unused numbers in one rate center into a single available pool from which carriers port only what they–as already exists for
191:(LNP), a technology that allowed subscribers to keep their existing telephone numbers when switching to a different provider in the same community. The original LNP database contract was granted in 1996.
1220:
198:
In 1998, the North
American Numbering Plan Administration estimated that the NANP would have run out of area codes for 10-digit telephone numbers by 2025 at then-current rates of depletion.
399:
landline exchange for each village — likely as a historical artifact of an earlier era when telcos built many small, local stations. While both villages are served by separate, unattended
213:
had implemented support for thousands-level routing of calls in its equipment by 1999. Pooling trials were conducted in 34 area codes across a dozen US states between 1997 and 2000.
184:, i.e. the allocation of number space in blocks of only 1,000 numbers (area code and one digit of line number), rather than of an entire central office prefix with 10,000 lines.
236:, a trade group of local telephone companies, to propose mandatory ten-digit dialing nationwide was rejected by the FCC in 2000. The FCC instead adopted many aspects of the
391:. Once a small incorporated village built around a saw mill, its town hall closed in 1922. The La Fargeville rate center's local calling area is the same as neighboring
371:
82:, meaning that it assigns telephone numbers to individual endpoints based on a fixed-length telephone number. The national telephone number consists of a three-digit
400:
362:
The
Pooling Administrator, a neutral third party, maintains no more than a six-month inventory of telephone numbers in each thousands-block number pool.
124:
service in 1983 created two competing carriers in each service area. Additional mobile carriers entered the market to provide digital service (such as
672:
890:
128:, introduced in 1991). In 1985, competitive access providers (CAPs) began to offer private line and special access services; originally based on
843:
654:
97:
do not use distinct area codes from wireline services, but many central offices provide only wireless services, or just wireline services.
267:
In some areas, decreased code demand and conservation efforts have allowed the introduction of proposed new area codes to be delayed.
768:
607:
1317:
944:
1165:"Rogers Wireless Partnership Part VII application regarding the requirement for a central office code in each served exchange"
718:
489:
in the entire numbering plan area for each municipality would quickly exhaust the number of central office codes of the NPA.
693:
370:, the North American Numbering Plan Administrator. Canada currently has no number pooling, but has been ordered by the
308:
Number pooling remains available to carriers on an optional basis in many US markets in which it is not yet mandatory.
347:
233:
63:
915:
865:
1221:"Somos, Inc. is Awarded the North American Numbering Plan Administration and the Pooling Administration Contracts"
966:
743:
313:
982:
CODE OF STATE REGULATIONS, Missouri
Department of Economic Development, Division 240—Public Service Commission,
818:
137:
17:
793:
249:
75:
46:
996:
377:
237:
180:(where the area code of existing numbers was changed), prompted the FCC and state commissions to introduce
117:
156:
numbers from a CLEC, deploy a server to feed the calls to broadband
Internet and offer telephone service.
517:
1312:
1140:
322:
101:
1285:
317:
176:(which allowed customers to keep their existing numbers, but broke seven-digit local calling) or by
658:
188:
55:
384:
151:
in the 1990s further blurred the boundaries between telcos and cable television providers. Every
129:
438:
426:
407:, Verizon nominally has a half-dozen competitors offering local numbers in tiny La Fargeville:
388:
380:
now include a "block ID" to indicate the ownership of the specific sub-blocks within a prefix.
256:
regulations requiring that carriers implement number pooling. By 2013, even sparsely populated
144:
58:
without structure changes of telephone numbers. Telephone number pooling was first tested for
79:
104:
on
January 1, 1984, most telephone service areas in the United States were dominated by one
983:
296:
was scrapped in 2003; it was later reinstated, and went into effect on March 3, 2018. An
8:
498:
404:
245:
87:
1164:
585:
458:
152:
133:
271:, proposed to overlay the portion of western Washington State currently in area codes
140:
required incumbent telephone companies (ILECs) to interconnect with the new entrants.
1001:
611:
392:
1242:
1023:
480:
94:
1263:
1082:"PL-332: PA 445 Implementation for 215/267 NPA Rescinded – 445 NPA Code Reclaimed"
1081:
673:"NeuStar Initiates Mandatory Number Pooling Trial for Connecticut's 203 Area Code"
220:, had already been subjected to multiple area code splits and a proposed overlay
177:
173:
1199:
1110:
1052:
105:
563:
1306:
468:
301:
297:
289:
284:
280:
276:
272:
268:
261:
226:
221:
202:
148:
59:
293:
121:
448:
367:
51:
919:
541:
366:
The default National Number Pool Administration in the United States is
1178:
891:"Citing Callers' Inconvenience, Fcc Rejects Mandatory 10-digit Dialing"
346:
According to 47 CFR 52.20, a US federal regulation administered by the
945:"Montana PSC Granted Authority to Implement Mandatory Number Pooling"
633:
161:
136:, these evolved into competitive local exchange carriers (CLEC). The
83:
42:
172:
Public resistance to the introduction of new area codes, whether as
62:
in Illinois in June 1998, and became national policy in a series of
206:
109:
396:
330:
326:
257:
217:
260:
was using number pooling in order to extend the useful life of
210:
1266:. Canadian Radio-television and Telecommunications Commission
187:
These developments largely coincided with the deployment of
844:"The 10- or 11-Digit Local Call Fosters Anxiety and Shrugs"
372:
Canadian Radio-television and Telecommunications Commission
244:
Number pooling was implemented in various areas (including
248:
in January 2002) with national rollout in the 100 largest
984:
Chapter 37—Number Pooling and Number Conservation Efforts
769:"Push For 2nd Code For 847 Area Crazy, Icc Chairman Says"
125:
916:"WUTC: Number pooling starts January 8, 2002 in Spokane"
1111:"PL-499: NPA 445 to Overlay NPA 215-267 (Pennsylvania)"
1243:"North American Numbering Plan Administrator - About"
634:"Expectations for a Number Pooling Trial in Illinois"
1118:
North American Numbering Plan Administration (NANPA)
1089:
North American Numbering Plan Administration (NANPA)
1060:
North American Numbering Plan Administration (NANPA)
1031:
North American Numbering Plan Administration (NANPA)
383:
An example of a small hamlet with number pooling is
1141:"PUC Dismisses Petition for 814 Area Code Relief"
1053:"PL-492: NPA 564 to Overlay NPA 360 (Washington)"
719:"Group Sees Invisible Solution To Area Code Woes"
201:An initial number pooling trial was conducted in
1304:
1024:"PL-298: Suspension of 564 Overlay (Washington)"
1200:"47 CFR 52.20 - Thousands-block number pooling"
518:"North American Numbering Plan Administration"
694:"Area Code Mess Fuels Outrage In Land Of 847"
586:"NeuStar Number Pool Tools - FAQ, Answers"
300:intended to split Pennsylvania's existing
1138:
167:
1264:"Telecom Regulatory Policy CRTC 2024-26"
1179:"LincMad on LNP and Number Conservation"
939:
937:
836:
655:"LNP and number pooling: a matched set?"
27:Method of reallocating telephone numbers
866:"Days are numbered for 7-digit dialing"
14:
1305:
994:
93:In the North American Numbering Plan,
934:
744:"11-digit Dialing May Be Put On Hold"
1139:McCracken, Denise (April 26, 2012).
578:
216:Area code 847, located northwest of
819:"11-digit dialing due for everyone"
50:the entire prefix is assigned to a
24:
264:, the one area code in the state.
25:
1329:
794:"The Artificial Area Code Crunch"
348:Federal Communications Commission
337:
234:United States Telecom Association
64:Federal Communications Commission
378:Local exchange routing databases
66:(FCC) orders from 2000 to 2003.
1278:
1256:
1235:
1213:
1192:
1171:
1157:
1132:
1103:
1074:
1045:
1016:
997:"No new area code for Syracuse"
988:
976:
959:
908:
883:
858:
811:
786:
761:
736:
711:
116:Widespread introduction of the
686:
665:
647:
626:
600:
556:
534:
510:
250:metropolitan statistical areas
182:thousands-block number pooling
138:Telecommunications Act of 1996
35:thousands-block number pooling
13:
1:
1318:North American Numbering Plan
995:Knauss, Tim (June 15, 2009).
610:. OC Register. Archived from
542:"Why So Many New Area Codes?"
504:
76:North American Numbering Plan
47:North American Numbering Plan
449:Inteliquent (formerly Onvoy)
238:Illinois Commerce Commission
118:Advanced Mobile Phone System
41:, is a method of allocating
7:
846:. NY Times. 23 January 2003
492:
416:Voxbeam Telecommunications
323:toll-free telephone numbers
10:
1334:
395:, yet there is a separate
252:(MSAs) on March 15, 2002.
102:breakup of the Bell System
69:
1012:– via syracuse.com.
387:(population 600), in the
374:to implement it by 2025.
318:local interconnect region
229:) was also unsuccessful.
401:remote switching centers
189:local number portability
132:(PBX) standards such as
56:telephone numbering plan
31:Telephone number pooling
385:La Fargeville, New York
130:private branch exchange
45:numbering space of the
439:Verizon Communications
427:Level 3 Communications
168:Testing and deployment
1288:. Local calling guide
80:closed numbering plan
1091:. September 24, 2003
614:on February 22, 1999
608:"Your number is up!"
1145:www.puc.state.pa.us
1120:. December 27, 2016
967:"Resolutions Index"
499:Numbering plan area
241:numbers to a pool.
88:central office code
922:on 24 October 2014
459:Broadview Networks
389:315/680 area codes
232:An attempt by the
153:broadband Internet
134:direct inward dial
1313:Telephone numbers
1033:. August 29, 2001
1002:The Post-Standard
564:"Company History"
486:
485:
393:Clayton, New York
174:overlay complexes
95:mobile telephones
16:(Redirected from
1325:
1298:
1297:
1295:
1293:
1286:"NPA-NXX search"
1282:
1276:
1275:
1273:
1271:
1260:
1254:
1253:
1251:
1249:
1239:
1233:
1232:
1230:
1228:
1217:
1211:
1210:
1208:
1206:
1196:
1190:
1189:
1187:
1185:
1175:
1169:
1168:
1167:. 12 April 2007.
1161:
1155:
1154:
1152:
1151:
1136:
1130:
1129:
1127:
1125:
1115:
1107:
1101:
1100:
1098:
1096:
1086:
1078:
1072:
1071:
1069:
1067:
1057:
1049:
1043:
1042:
1040:
1038:
1028:
1020:
1014:
1013:
1011:
1010:
992:
986:
980:
974:
973:
971:
963:
957:
956:
954:
952:
941:
932:
931:
929:
927:
918:. Archived from
912:
906:
905:
903:
901:
887:
881:
880:
878:
876:
862:
856:
855:
853:
851:
840:
834:
833:
831:
829:
815:
809:
808:
806:
804:
790:
784:
783:
781:
779:
765:
759:
758:
756:
754:
740:
734:
733:
731:
729:
715:
709:
708:
706:
704:
690:
684:
683:
681:
679:
669:
663:
662:
657:. Archived from
651:
645:
644:
642:
640:
630:
624:
623:
621:
619:
604:
598:
597:
595:
593:
582:
576:
575:
573:
571:
560:
554:
553:
551:
549:
538:
532:
531:
529:
528:
522:
514:
410:
409:
403:controlled from
178:area code splits
86:, a three-digit
21:
1333:
1332:
1328:
1327:
1326:
1324:
1323:
1322:
1303:
1302:
1301:
1291:
1289:
1284:
1283:
1279:
1269:
1267:
1262:
1261:
1257:
1247:
1245:
1241:
1240:
1236:
1226:
1224:
1219:
1218:
1214:
1204:
1202:
1198:
1197:
1193:
1183:
1181:
1177:
1176:
1172:
1163:
1162:
1158:
1149:
1147:
1137:
1133:
1123:
1121:
1113:
1109:
1108:
1104:
1094:
1092:
1084:
1080:
1079:
1075:
1065:
1063:
1062:. June 28, 2016
1055:
1051:
1050:
1046:
1036:
1034:
1026:
1022:
1021:
1017:
1008:
1006:
993:
989:
981:
977:
969:
965:
964:
960:
950:
948:
943:
942:
935:
925:
923:
914:
913:
909:
899:
897:
895:Chicago Tribune
889:
888:
884:
874:
872:
870:Chicago Tribune
864:
863:
859:
849:
847:
842:
841:
837:
827:
825:
823:Chicago Tribune
817:
816:
812:
802:
800:
798:Chicago Tribune
792:
791:
787:
777:
775:
773:Chicago Tribune
767:
766:
762:
752:
750:
748:Chicago Tribune
742:
741:
737:
727:
725:
723:Chicago Tribune
717:
716:
712:
702:
700:
698:Chicago Tribune
692:
691:
687:
677:
675:
671:
670:
666:
653:
652:
648:
638:
636:
632:
631:
627:
617:
615:
606:
605:
601:
591:
589:
584:
583:
579:
569:
567:
562:
561:
557:
547:
545:
540:
539:
535:
526:
524:
520:
516:
515:
511:
507:
495:
476:
434:
422:
340:
312:prefix in each
209:in April 1998.
170:
72:
28:
23:
22:
15:
12:
11:
5:
1331:
1321:
1320:
1315:
1300:
1299:
1277:
1255:
1234:
1212:
1191:
1170:
1156:
1131:
1102:
1073:
1044:
1015:
1005:. Syracuse, NY
987:
975:
958:
933:
907:
882:
857:
835:
810:
785:
760:
735:
710:
685:
664:
661:on 2013-06-29.
646:
625:
599:
577:
555:
533:
508:
506:
503:
502:
501:
494:
491:
484:
483:
478:
472:
471:
466:
462:
461:
456:
452:
451:
446:
442:
441:
436:
430:
429:
424:
418:
417:
414:
364:
363:
360:
356:
339:
338:Implementation
336:
169:
166:
143:Deployment of
71:
68:
39:number pooling
26:
18:Number pooling
9:
6:
4:
3:
2:
1330:
1319:
1316:
1314:
1311:
1310:
1308:
1287:
1281:
1265:
1259:
1244:
1238:
1223:. PR Newswire
1222:
1216:
1201:
1195:
1180:
1174:
1166:
1160:
1146:
1142:
1135:
1119:
1112:
1106:
1090:
1083:
1077:
1061:
1054:
1048:
1032:
1025:
1019:
1004:
1003:
998:
991:
985:
979:
968:
962:
946:
940:
938:
921:
917:
911:
896:
892:
886:
871:
867:
861:
845:
839:
824:
820:
814:
799:
795:
789:
774:
770:
764:
749:
745:
739:
724:
720:
714:
699:
695:
689:
674:
668:
660:
656:
650:
635:
629:
613:
609:
603:
587:
581:
565:
559:
543:
537:
519:
513:
509:
500:
497:
496:
490:
482:
479:
474:
473:
470:
469:Bandwidth.com
467:
464:
463:
460:
457:
454:
453:
450:
447:
444:
443:
440:
437:
432:
431:
428:
425:
420:
419:
415:
412:
411:
408:
406:
402:
398:
394:
390:
386:
381:
379:
375:
373:
369:
361:
357:
353:
352:
351:
349:
344:
335:
332:
329:database and
328:
324:
319:
315:
309:
306:
303:
302:area code 814
299:
298:area code 582
295:
291:
290:area code 445
286:
282:
278:
274:
270:
269:Area code 564
265:
263:
262:area code 406
259:
253:
251:
247:
242:
239:
235:
230:
228:
223:
222:area code 224
219:
214:
212:
208:
204:
203:area code 847
199:
196:
192:
190:
185:
183:
179:
175:
165:
163:
157:
154:
150:
149:voice over IP
146:
141:
139:
135:
131:
127:
123:
119:
114:
111:
108:which held a
107:
103:
98:
96:
91:
89:
85:
81:
77:
67:
65:
61:
60:area code 847
57:
53:
48:
44:
40:
36:
32:
19:
1290:. Retrieved
1280:
1268:. Retrieved
1258:
1246:. Retrieved
1237:
1225:. Retrieved
1215:
1203:. Retrieved
1194:
1182:. Retrieved
1173:
1159:
1148:. Retrieved
1144:
1134:
1122:. Retrieved
1117:
1105:
1093:. Retrieved
1088:
1076:
1064:. Retrieved
1059:
1047:
1035:. Retrieved
1030:
1018:
1007:. Retrieved
1000:
990:
978:
961:
949:. Retrieved
924:. Retrieved
920:the original
910:
898:. Retrieved
894:
885:
873:. Retrieved
869:
860:
848:. Retrieved
838:
826:. Retrieved
822:
813:
801:. Retrieved
797:
788:
776:. Retrieved
772:
763:
751:. Retrieved
747:
738:
726:. Retrieved
722:
713:
701:. Retrieved
697:
688:
676:. Retrieved
667:
659:the original
649:
637:. Retrieved
628:
616:. Retrieved
612:the original
602:
590:. Retrieved
580:
568:. Retrieved
558:
546:. Retrieved
536:
525:. Retrieved
512:
487:
382:
376:
365:
345:
341:
310:
307:
294:Philadelphia
266:
254:
243:
231:
215:
200:
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158:
145:cable modems
142:
122:mobile phone
115:
99:
92:
73:
38:
34:
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29:
1248:8 September
1227:8 September
292:overlaying
52:rate center
1307:Categories
1292:4 November
1270:8 February
1205:4 November
1184:4 November
1150:2017-04-01
1009:2017-03-31
951:4 November
926:4 November
900:4 November
875:4 November
850:4 November
828:4 November
803:4 November
778:4 November
753:4 November
728:4 November
703:4 November
678:4 November
639:4 November
618:4 November
592:4 November
570:4 November
548:4 November
527:2023-06-18
505:References
477:315-658-9
465:315-658-7
455:315-658-5
445:315-658-3
435:315-658-4
423:315-658-6
413:315-658-0
162:area codes
100:After the
37:, or just
588:. Neustar
566:. Neustar
544:. LincMad
475:315-658-8
433:315-658-2
421:315-658-1
405:Watertown
325:with the
84:area code
43:telephony
1124:April 1,
1095:April 1,
1066:April 1,
1037:April 1,
493:See also
481:Spectrum
207:Illinois
110:monopoly
397:Verizon
355:center.
331:RespOrg
327:SMS/800
258:Montana
246:Spokane
218:Chicago
120:(AMPS)
106:carrier
70:History
523:. 2022
359:block.
283:, and
211:Nortel
1114:(PDF)
1085:(PDF)
1056:(PDF)
1027:(PDF)
970:(PDF)
947:. FCC
521:(PDF)
368:Somos
78:is a
1294:2014
1272:2024
1250:2020
1229:2020
1207:2014
1186:2014
1126:2017
1097:2017
1068:2017
1039:2017
953:2014
928:2014
902:2014
877:2014
852:2014
830:2014
805:2014
780:2014
755:2014
730:2014
705:2014
680:2014
641:2014
620:2014
594:2014
572:2014
550:2014
314:LATA
147:and
74:The
316:or
285:425
281:360
277:253
273:206
227:212
205:in
126:GSM
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