Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records
Area code 231 prefixes
572 of the 786 possible NXX blocks are assigned in area code 231 (72.8% of capacity), spread across 99 rate centers and 42 holders. The largest holders are NEW CINGULAR WIRELESS PCS, LLC - IL (72 blocks, 12.6%), MICHIGAN BELL TEL CO (71 blocks, 12.4%), FRONTIER NORTH, INC. - MI (52 blocks, 9.1%). Grouped by brand, AT&T accounts for 154 blocks; brand-attributable holders cover 78% 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 2001-01-09 to 2026-03-19, with 62 blocks handed out in 2002 alone. 382 blocks (67%) 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. 77 were growth assignments – additional blocks to a carrier that had already filled its earlier ones.
572 assigned blocks of 786
99 rate centers
42 holders of record
67% in thousands-block pooling
Largest holders in 231
| Holder of record, as NANPA names it | Brand | Blocks | Share |
|---|---|---|---|
| NEW CINGULAR WIRELESS PCS, LLC - IL | AT&T | 72 | 12.6% |
| MICHIGAN BELL TEL CO | AT&T | 71 | 12.4% |
| FRONTIER NORTH, INC. - MI | Frontier | 52 | 9.1% |
| ONVOY, LLCV - MI | Onvoy | 49 | 8.6% |
| INTERACTIVE SERVICES NETWORK, INC. | – | 43 | 7.5% |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | Verizon | 42 | 7.3% |
| 123.NET, LLC | – | 34 | 5.9% |
| OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | T-Mobile | 28 | 4.9% |
| CHARTER IP ENABLED SERVICES, LLC | Charter | 20 | 3.5% |
| LEVEL 3 COMMUNICATIONS, LLC - MI | Lumen | 19 | 3.3% |
| BANDWIDTH.COM CLEC, LLC - MI | Bandwidth | 19 | 3.3% |
| BRIGHTSPEED OF MICHIGAN, LLC | Brightspeed | 15 | 2.6% |
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.
MUSKEGON 68TRAVERSECY 53PETOSKEY 22CADILLAC 21BIG RAPIDS 19LUDINGTON 14CHEBOYGAN 13MANISTEE 12KALKASKA 10FREMONT 9NEWAYGO 9BOYNE CITY 8FRANKFORT 7HARBOR SPG 7CHARLEVOIX 7HART 7REED CITY 7NORTHPORT 7BEULAH 7FIFE LAKE 6GLEN LAKE 6MORLEY 6MCBAIN 6EVART 6EASTJORDAN 5ELMIRA 5CORAL 5MANCELONA 5GRANT 5WHITEHALL 5MACKINAWCY 5BALDWIN 5BELLAIRE 5SCOTTVILLE 5WOLVERINE 5MECOSTA 4ALANSON 4HONOR 4MOORESTOWN 4LAKE CITY 4LAKE ANN 4PENTWATER 4WILLIAMSBG 4ONEKAMA 4SHELBY 4ALDEN 4CENTRAL LK 4FRUITPORT 4WHITECLOUD 4HOWARDCITY 4BRUTUS 3BOYNEFALLS 3SUTTONSBAY 3INTERLOCHN 3BEAR LAKE 3MERRITT 3LEVERING 3INDIAN RIV 3LKLEELANAU 3KINGSLEY 3
All 572 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.
| Prefix | Holder of record | Rate center | Assigned | Pooled | In service |
|---|---|---|---|---|---|
| 231-201 | AT&T | CHIPPEWALK | 2004-03-05 | yes | yes |
| 231-202 | AT&T | MECOSTA | 2004-03-05 | yes | yes |
| 231-203 | AT&T | ALANSON | 2004-03-19 | yes | yes |
| 231-204 | Spok | FIFE LAKE | – | – | yes |
| 231-205 | INTERACTIVE SERVICES NETWORK, INC. | BRUTUS | 2004-03-24 | – | yes |
| 231-206 | T-Mobile | MUSKEGON | – | yes | yes |
| 231-207 | INTERACTIVE SERVICES NETWORK, INC. | HONOR | 2004-03-24 | – | yes |
| 231-208 | INTERACTIVE SERVICES NETWORK, INC. | BOYNEFALLS | 2004-03-24 | – | yes |
| 231-209 | INTERACTIVE SERVICES NETWORK, INC. | SUTTONSBAY | 2004-03-25 | – | yes |
| 231-210 | Onvoy | ST JAMES | 2023-07-11 | yes | yes |
| 231-212 | Lumen | INTERLOCHN | 2016-07-25 | yes | yes |
| 231-213 | AT&T | TRAVERSECY | 2015-03-26 | yes | yes |
| 231-214 | Charter | LAKE NORTH | 2025-03-12 | yes | yes |
| 231-215 | Verizon | MUSKEGON | – | – | yes |
| 231-216 | Peerless | FRANKFORT | 2015-12-01 | yes | yes |
| 231-217 | INTERACTIVE SERVICES NETWORK, INC. | BEAR LAKE | 2004-03-24 | – | yes |
| 231-218 | T-Mobile | TRAVERSECY | – | yes | yes |
| 231-219 | INTERACTIVE SERVICES NETWORK, INC. | MERRITT | 2004-03-24 | – | yes |
| 231-220 | 123.NET, LLC | MUSKEGON | 2003-03-25 | yes | yes |
| 231-221 | Lumen | HARBOR SPG | 2015-06-01 | yes | yes |
| 231-222 | Lumen | EASTJORDAN | 2002-04-04 | yes | yes |
| 231-223 | ACE TEL. CO. OF MICHIGAN, INC. | OLDMISSION | – | yes | yes |
| 231-224 | Bandwidth | FREMONT | – | yes | yes |
| 231-225 | Lumen | FREMONT | 2002-04-04 | yes | yes |
| 231-226 | INTERACTIVE SERVICES NETWORK, INC. | GLEN LAKE | 2004-03-24 | – | yes |
| 231-227 | Charter | HONOR | 2012-09-26 | yes | yes |
| 231-228 | Brightspeed | GLEN LAKE | – | – | yes |
| 231-229 | Brightspeed | MOORESTOWN | – | – | yes |
| 231-230 | INTERACTIVE SERVICES NETWORK, INC. | ELMIRA | 2004-03-24 | – | yes |
| 231-232 | INTERACTIVE SERVICES NETWORK, INC. | MOORESTOWN | 2004-03-24 | – | yes |
| 231-233 | Verizon | LUDINGTON | 2004-08-30 | – | yes |
| 231-234 | Charter | BUCKLEY | 2015-12-07 | yes | yes |
| 231-235 | INTERACTIVE SERVICES NETWORK, INC. | LEVERING | 2004-03-24 | – | yes |
| 231-236 | INTERACTIVE SERVICES NETWORK, INC. | LAKE CITY | 2004-03-24 | – | yes |
| 231-237 | AT&T | CHARLEVOIX | – | yes | yes |
| 231-238 | AT&T | INDIAN RIV | – | yes | yes |
| 231-239 | Verizon | LUDINGTON | 2004-04-28 | yes | yes |
| 231-240 | INTERACTIVE SERVICES NETWORK, INC. | LAKE ANN | 2004-03-24 | – | yes |
| 231-241 | DAYSTARR LLC DBA DAYSTARR COMMUNICATIONS | PENTWATER | 2006-10-10 | yes | yes |
| 231-242 | AT&T | HARBOR SPG | – | yes | yes |
| 231-243 | INTERACTIVE SERVICES NETWORK, INC. | ALANSON | 2004-03-24 | – | yes |
| 231-244 | Lumen | BOYNE CITY | 2015-08-26 | yes | yes |
| 231-245 | AT&T | NEWAYGO | 2009-07-17 | yes | yes |
| 231-246 | Comcast | MUSKEGON | 2015-12-22 | yes | yes |
| 231-247 | Bandwidth | WILLIAMSBG | 2018-09-28 | yes | yes |
| 231-249 | Bandwidth | CHEBOYGAN | – | – | yes |
| 231-250 | Verizon | BIG RAPIDS | – | – | yes |
| 231-251 | Peerless | LKLEELANAU | 2015-12-02 | yes | yes |
| 231-252 | Bandwidth | TRAVERSECY | 2016-04-18 | yes | yes |
| 231-253 | T-Mobile | CADILLAC | 2018-11-08 | yes | yes |
| 231-254 | T-Mobile | PETOSKEY | 2019-10-24 | yes | yes |
| 231-255 | Spok | ONEKAMA | – | – | yes |
| 231-256 | AT&T | LKLEELANAU | – | yes | yes |
| 231-257 | PENINSULA FIBER NETWORK, LLC - MI | LAKE CITY | 2019-02-27 | yes | yes |
| 231-258 | AT&T | KALKASKA | – | – | yes |
| 231-259 | Charter | SHELBY | 2007-02-07 | yes | yes |
| 231-260 | T-Mobile | MUSKEGON | 2017-03-03 | yes | yes |
| 231-261 | PENINSULA FIBER NETWORK, LLC - MI | LUDINGTON | 2018-12-31 | yes | yes |
| 231-262 | ACD TELECOM, INC. - MI | ELMIRA | 2005-01-21 | yes | yes |
| 231-263 | Brightspeed | KINGSLEY | – | yes | yes |
| 231-264 | AT&T | ELK RAPIDS | – | yes | yes |
| 231-265 | Charter | CORAL | 2014-05-19 | yes | yes |
| 231-266 | AT&T | IRONS | – | yes | yes |
| 231-267 | AT&T | WILLIAMSBG | – | yes | yes |
| 231-268 | Verizon | CHEBOYGAN | 2004-07-12 | yes | yes |
| 231-269 | ACE TEL. CO. OF MICHIGAN, INC. | BUCKLEY | – | – | yes |
| 231-270 | Onvoy | BOYNE CITY | 2021-05-21 | yes | yes |
| 231-271 | Brightspeed | SUTTONSBAY | – | – | yes |
| 231-272 | Onvoy | KINGSLEY | 2019-08-08 | yes | yes |
| 231-273 | Onvoy | EASTPORT | 2020-10-26 | yes | yes |
| 231-274 | American Messaging | TRAVERSECY | – | – | yes |
| 231-275 | Brightspeed | LAKE ANN | – | – | yes |
| 231-276 | AT&T | INTERLOCHN | – | yes | yes |
| 231-277 | Onvoy | FOUNTAIN | 2016-03-22 | yes | yes |
| 231-278 | Charter | HESPERIA | 2020-10-26 | yes | yes |
| 231-279 | Lumen | BIG RAPIDS | 2019-12-20 | yes | yes |
| 231-280 | Onvoy | MANCELONA | 2016-02-29 | yes | yes |
| 231-281 | AT&T | CADILLAC | 2020-11-03 | yes | yes |
| 231-282 | AT&T | GRANT | – | yes | yes |
| 231-283 | Onvoy | MUSKEGON | 2020-11-09 | yes | yes |
| 231-284 | T-Mobile | MANISTEE | 2021-03-01 | yes | yes |
| 231-285 | T-Mobile | CADILLAC | 2020-01-09 | yes | yes |
| 231-286 | Verizon | MUSKEGON | – | – | yes |
| 231-287 | Verizon | BIG RAPIDS | – | yes | yes |
| 231-288 | AT&T | MUSKEGON | 2005-09-13 | yes | yes |
| 231-289 | Bandwidth | CHARLEVOIX | 2018-07-19 | yes | yes |
| 231-290 | AT&T | INDIAN RIV | – | yes | yes |
| 231-291 | INTERACTIVE SERVICES NETWORK, INC. | MUSKEGON | 2012-05-11 | yes | yes |
| 231-292 | Charter | WHITEHALL | 2010-07-30 | yes | yes |
| 231-293 | HD CARRIER LLC | FRANKFORT | 2021-05-14 | yes | yes |
| 231-294 | Onvoy | FIFE LAKE | 2021-06-15 | yes | yes |
| 231-295 | Charter | LAKE CITY | 2012-09-26 | yes | yes |
| 231-296 | Charter | FREMONT | 2021-05-13 | yes | yes |
| 231-297 | Onvoy | KINGSLEY | 2021-06-25 | yes | yes |
| 231-298 | Charter | IRONS | 2021-05-13 | yes | yes |
| 231-299 | T-Mobile | MANISTEE | 2011-12-28 | yes | yes |
| 231-300 | Onvoy | ALDEN | 2017-09-07 | yes | yes |
| 231-301 | Verizon | HART | – | yes | yes |
| 231-302 | Bandwidth | PETOSKEY | – | – | yes |
| 231-303 | AT&T | NEWAYGO | 2011-05-16 | yes | yes |
| 231-304 | Onvoy | BRUTUS | 2020-10-26 | yes | yes |
| 231-305 | INTERACTIVE SERVICES NETWORK, INC. | BIG RAPIDS | – | – | yes |
| 231-306 | INTERACTIVE SERVICES NETWORK, INC. | CADILLAC | – | – | yes |
| 231-307 | AT&T | MORLEY | – | yes | yes |
| 231-308 | INTERACTIVE SERVICES NETWORK, INC. | CHARLEVOIX | – | – | yes |
| 231-309 | INTERACTIVE SERVICES NETWORK, INC. | MANISTEE | – | – | yes |
| 231-310 | Onvoy | FALMOUTH | 2018-09-25 | yes | yes |
| 231-312 | INTERACTIVE SERVICES NETWORK, INC. | FRANKFORT | – | – | yes |
| 231-313 | AT&T | TRAVERSECY | – | – | yes |
| 231-314 | INTERACTIVE SERVICES NETWORK, INC. | KALKASKA | – | – | yes |
| 231-315 | Spok | MUSKEGON | – | – | yes |
| 231-316 | INTERACTIVE SERVICES NETWORK, INC. | LUDINGTON | – | – | yes |
| 231-317 | Spok | BOYNE CITY | – | – | yes |
| 231-318 | Spok | TRAVERSECY | – | – | yes |
| 231-319 | INTERACTIVE SERVICES NETWORK, INC. | MACKINAWCY | – | – | yes |
| 231-320 | Bandwidth | TRCHRIVBDG | 2021-09-03 | yes | yes |
| 231-321 | Verizon | ELMIRA | 2021-05-19 | yes | yes |
| 231-322 | Frontier | TRCHRIVBDG | – | yes | yes |
| 231-323 | Bandwidth | EASTJORDAN | – | – | yes |
| 231-324 | AT&T | HARBOR SPG | 2021-05-25 | yes | yes |
| 231-325 | Brightspeed | HONOR | – | – | yes |
| 231-326 | Brightspeed | GLEN LAKE | – | – | yes |
| 231-327 | AT&T | MUSKEGON | – | yes | yes |
| 231-328 | Brightspeed | MERRITT | – | yes | yes |
| 231-329 | AT&T | MUSKEGON | – | – | yes |
| 231-330 | Verizon | PETOSKEY | 2002-12-10 | – | yes |
| 231-331 | Frontier | ALDEN | – | yes | yes |
| 231-332 | INTERACTIVE SERVICES NETWORK, INC. | MUSKEGON | – | – | yes |
| 231-333 | Lumen | CHEBOYGAN | 2002-04-04 | yes | yes |
| 231-334 | Brightspeed | GLEN LAKE | – | – | yes |
| 231-335 | AT&T | FREMONT | – | yes | yes |
| 231-336 | Spok | LUDINGTON | – | – | yes |
| 231-337 | AT&T | MCBAIN | – | – | yes |
| 231-338 | Bandwidth | BALDWIN | – | yes | yes |
| 231-339 | American Messaging | MUSKEGON | – | – | yes |
| 231-340 | Verizon | ELMIRA | 2003-07-09 | yes | yes |
| 231-341 | AT&T | LAKE ANN | 2025-05-22 | yes | yes |
| 231-342 | Verizon | TRAVERSECY | – | – | yes |
| 231-343 | T-Mobile | MUSKEGON | – | yes | yes |
| 231-344 | INTERACTIVE SERVICES NETWORK, INC. | PETOSKEY | – | – | yes |
| 231-345 | Bandwidth | REED CITY | – | yes | yes |
| 231-346 | INTERACTIVE SERVICES NETWORK, INC. | TRAVERSECY | – | – | yes |
| 231-347 | AT&T | PETOSKEY | – | – | yes |
| 231-348 | AT&T | PETOSKEY | – | – | yes |
| 231-349 | Verizon | BIG RAPIDS | – | – | yes |
| 231-350 | Verizon | BELLAIRE | 2003-07-09 | yes | yes |
| 231-351 | INTERACTIVE SERVICES NETWORK, INC. | SCOTTVILLE | – | – | yes |
| 231-352 | AT&T | FRANKFORT | – | yes | yes |
| 231-353 | INTERACTIVE SERVICES NETWORK, INC. | MCBAIN | – | – | yes |
| 231-354 | AT&T | CORAL | – | yes | yes |
| 231-355 | INTERACTIVE SERVICES NETWORK, INC. | FREMONT | – | – | yes |
| 231-356 | INTERACTIVE SERVICES NETWORK, INC. | MANCELONA | – | – | yes |
| 231-357 | Verizon | TRAVERSECY | – | – | yes |
| 231-358 | INTERACTIVE SERVICES NETWORK, INC. | CENTRAL LK | – | – | yes |
| 231-359 | Charter | MECOSTA | 2012-09-26 | yes | yes |
| 231-360 | AT&T | TRAVERSECY | 2002-12-30 | yes | yes |
| 231-361 | INTERACTIVE SERVICES NETWORK, INC. | MORLEY | – | – | yes |
| 231-362 | KALEVA TEL. CO. | KALEVA | – | – | yes |
| 231-363 | INTERACTIVE SERVICES NETWORK, INC. | CHEBOYGAN | – | – | yes |
| 231-364 | Onvoy | NORTHPORT | 2021-06-15 | yes | yes |
| 231-365 | INTERACTIVE SERVICES NETWORK, INC. | WOLVERINE | – | – | yes |
| 231-366 | Lumen | FRUITPORT | 2003-02-27 | yes | yes |
| 231-367 | Onvoy | WOLVERINE | 2021-06-25 | yes | yes |
| 231-368 | INTERACTIVE SERVICES NETWORK, INC. | BALDWIN | – | – | yes |
| 231-369 | ACE TEL. CO. OF MICHIGAN, INC. | SOBOARDMAN | – | – | yes |
| 231-370 | T-Mobile | MUSKEGON | 2021-09-03 | yes | yes |
| 231-371 | Bandwidth | TUSTIN | 2021-09-03 | yes | yes |
| 231-372 | INTERACTIVE SERVICES NETWORK, INC. | EVART | – | – | yes |
| 231-373 | Verizon | PETOSKEY | 2004-04-27 | yes | yes |
| 231-374 | Onvoy | SHELBY | 2021-06-15 | yes | yes |
| 231-375 | Verizon | MUSKEGON | – | yes | yes |
| 231-376 | Onvoy | TWIN LAKE | 2021-07-02 | yes | yes |
| 231-377 | Frontier | CLAM RIVER | – | yes | yes |
| 231-378 | ACE TEL. CO. OF MICHIGAN, INC. | COPESHTNVL | – | – | yes |
| 231-379 | Bandwidth | ONEKAMA | 2021-08-26 | yes | yes |
| 231-380 | T-Mobile | NEWAYGO | 2022-01-10 | yes | yes |
| 231-381 | Charter | WHITECLOUD | 2021-05-13 | yes | yes |
| 231-383 | Verizon | BEULAH | 2003-04-29 | yes | yes |
| 231-384 | Verizon | KALKASKA | 2003-05-01 | yes | yes |
| 231-385 | Onvoy | CORAL | 2021-07-20 | yes | yes |
| 231-386 | AT&T | NORTHPORT | – | yes | yes |
| 231-387 | AT&T | PETOSKEY | 2021-10-06 | yes | yes |
| 231-388 | Verizon | LE ROY | 2003-05-01 | yes | yes |
| 231-389 | AT&T | HARRIETTA | – | yes | yes |
| 231-390 | T-Mobile | BIG RAPIDS | 2021-10-26 | yes | yes |
| 231-391 | Bandwidth | WALLOON LK | 2022-03-10 | yes | yes |
| 231-392 | T-Mobile | TRAVERSECY | 2001-01-09 | yes | yes |
| 231-393 | Charter | LE ROY | 2021-07-02 | yes | yes |
| 231-394 | Verizon | MOORESTOWN | 2003-07-29 | yes | yes |
| 231-395 | INTERACTIVE SERVICES NETWORK, INC. | GRANT | – | – | yes |
| 231-396 | Onvoy | CADILLAC | 2021-10-29 | yes | yes |
| 231-397 | T-Mobile | MANISTEE | 2021-11-03 | yes | yes |
| 231-398 | AT&T | MANISTEE | – | yes | yes |
| 231-399 | ACD TELECOM, INC. - MI | FRANKFORT | 2005-01-19 | yes | yes |
| 231-400 | Onvoy | ALANSON | 2019-10-10 | yes | yes |
| 231-401 | PENINSULA FIBER NETWORK, LLC - MI | TRAVERSECY | 2021-12-21 | yes | yes |
| 231-402 | Onvoy | MUSKEGON | 2022-01-21 | yes | yes |
| 231-403 | AT&T | WILLIAMSBG | 2011-08-16 | yes | yes |
| 231-404 | AT&T | STANWOOD | 2004-10-05 | yes | yes |
| 231-405 | Onvoy | ALDEN | 2022-02-04 | yes | yes |
| 231-406 | Onvoy | FALMOUTH | 2022-02-04 | yes | yes |
| 231-407 | Onvoy | MECOSTA | 2022-02-04 | yes | yes |
| 231-408 | AT&T | BIG RAPIDS | – | yes | yes |
| 231-409 | AT&T | TRAVERSECY | – | – | yes |
| 231-410 | AT&T | MANISTEE | 2022-08-12 | yes | yes |
| 231-412 | Bandwidth | HARBOR SPG | 2010-10-11 | yes | yes |
| 231-413 | T-Mobile | KALKASKA | 2022-02-14 | yes | yes |
| 231-414 | AT&T | NEWAYGO | – | yes | yes |
| 231-415 | Charter | DUBLIN | 2022-12-05 | yes | yes |
| 231-416 | American Messaging | BIG RAPIDS | – | – | yes |
| 231-417 | AT&T | PETOSKEY | 2023-01-06 | yes | yes |
| 231-418 | Onvoy | MARION | 2023-07-11 | yes | yes |
| 231-419 | Onvoy | BELLAIRE | 2023-07-11 | yes | yes |
| 231-420 | Verizon | CHEBOYGAN | – | – | yes |
| 231-421 | Charter | TRAVERSECY | 2002-02-20 | yes | yes |
| 231-422 | Lumen | PELLSTON | 2015-08-25 | yes | yes |
| 231-423 | Bandwidth | EVART | – | – | yes |
| 231-424 | ACD TELECOM, INC. - MI | CARR | 2005-01-27 | yes | yes |
| 231-425 | T-Mobile | LUDINGTON | – | yes | yes |
| 231-426 | Onvoy | RAVENNA | 2023-07-11 | yes | yes |
| 231-427 | AT&T | MACKINAWCY | 2011-08-17 | yes | yes |
| 231-428 | Onvoy | MUSKEGON | 2023-07-14 | yes | yes |
| 231-429 | Verizon | CADILLAC | 2002-12-05 | – | yes |
| 231-430 | Onvoy | BOYNE CITY | 2023-07-14 | yes | yes |
| 231-431 | Onvoy | CLAM RIVER | 2021-05-19 | yes | yes |
| 231-432 | AT&T | NORTHPORT | 2002-08-30 | yes | yes |
| 231-433 | Verizon | MOORESTOWN | 2011-04-29 | yes | yes |
| 231-434 | AT&T | MANTON | 2014-09-26 | yes | yes |
| 231-435 | Onvoy | EASTPORT | 2023-07-14 | yes | yes |
| 231-436 | AT&T | MACKINAWCY | – | yes | yes |
| 231-437 | T-Mobile | CHARLEVOIX | – | yes | yes |
| 231-438 | Onvoy | HARBOR SPG | 2023-07-14 | yes | yes |
| 231-439 | AT&T | PETOSKEY | – | – | yes |
| 231-440 | 123.NET, LLC | BALDWIN | 2002-08-27 | yes | yes |
| 231-441 | 123.NET, LLC | FIFE LAKE | 2002-08-27 | – | yes |
| 231-442 | Peerless | HARRIETTA | 2015-12-01 | yes | yes |
| 231-443 | Onvoy | HONOR | 2021-01-08 | yes | yes |
| 231-444 | Onvoy | CADILLAC | 2015-08-24 | yes | yes |
| 231-445 | Verizon | CHEBOYGAN | 2004-08-24 | yes | yes |
| 231-446 | Onvoy | NORTHPORT | 2023-07-14 | yes | yes |
| 231-447 | Onvoy | HOLTON | 2015-12-02 | yes | yes |
| 231-448 | ISLAND TEL. CO. | ST JAMES | – | yes | yes |
| 231-449 | Charter | BALDWIN | 2021-05-13 | yes | yes |
| 231-450 | AT&T | HESPERIA | 2005-01-19 | yes | yes |
| 231-451 | Onvoy | WILLIAMSBG | 2023-07-14 | yes | yes |
| 231-452 | Comcast | NEWAYGO | – | yes | yes |
| 231-453 | Charter | HOLTON | 2024-03-01 | yes | yes |
| 231-454 | T-Mobile | TRAVERSECY | 2021-09-23 | yes | yes |
| 231-455 | Onvoy | PENTWATER | 2021-01-08 | yes | yes |
| 231-456 | AT&T | GLEN LAKE | 2024-09-05 | yes | yes |
| 231-457 | ACD TELECOM, INC. - MI | MUSKEGON | – | yes | yes |
| 231-459 | Windstream | BOYNE CITY | 2004-01-09 | yes | yes |
| 231-460 | Onvoy | BIG RAPIDS | – | yes | yes |
| 231-462 | AT&T | FOUNTAIN | – | yes | yes |
| 231-463 | Verizon | TRAVERSECY | – | yes | yes |
| 231-464 | AT&T | FREESOIL | – | yes | yes |
| 231-465 | AT&T | REED CITY | – | yes | yes |
| 231-466 | Charter | EVART | 2021-07-02 | yes | yes |
| 231-468 | T-Mobile | CADILLAC | 2001-02-05 | yes | yes |
| 231-469 | AT&T | MUSKEGON | 2026-03-19 | yes | yes |
| 231-475 | Bandwidth | MANTON | – | yes | yes |
| 231-477 | KALEVA TEL. CO. | BRETHREN | – | – | yes |
| 231-480 | Lumen | LUDINGTON | 2002-05-23 | yes | yes |
| 231-484 | AT&T | EASTJORDAN | 2013-08-07 | yes | yes |
| 231-486 | Verizon | TRAVERSECY | – | yes | yes |
| 231-487 | AT&T | PETOSKEY | – | yes | yes |
| 231-488 | 123.NET, LLC | MANISTEE | 2002-08-27 | – | yes |
| 231-489 | PENINSULA FIBER NETWORK, LLC - MI | PETOSKEY | 2015-04-21 | yes | yes |
| 231-492 | Verizon | TRAVERSECY | – | yes | yes |
| 231-493 | T-Mobile | TRAVERSECY | 2017-05-17 | yes | yes |
| 231-494 | American Messaging | BIG RAPIDS | – | – | yes |
| 231-495 | AT&T | BELLAIRE | 2016-07-29 | yes | yes |
| 231-497 | AT&T | BOYNE CITY | – | yes | yes |
| 231-498 | Lumen | ELK RAPIDS | 2004-10-20 | yes | yes |
| 231-499 | Verizon | TRAVERSECY | – | – | yes |
| 231-500 | Onvoy | WHITEHALL | 2019-10-10 | yes | yes |
| 231-508 | KALEVA TELEPHONE COMPANY - MI | ONEKAMA | 2008-06-03 | yes | yes |
| 231-510 | AT&T | MANISTEE | – | – | yes |
| 231-512 | American Messaging | TRAVERSECY | – | – | yes |
| 231-514 | American Messaging | CADILLAC | – | – | yes |
| 231-515 | ACD TELECOM, INC. - MI | EVART | 2005-01-19 | yes | yes |
| 231-516 | American Messaging | PETOSKEY | – | – | yes |
| 231-518 | Lumen | KALKASKA | 2001-06-18 | yes | yes |
| 231-519 | Verizon | NEWAYGO | 2002-07-19 | – | yes |
| 231-520 | 123.NET, LLC | CHARLEVOIX | 2002-08-27 | – | yes |
| 231-522 | 123.NET, LLC | LUTHER | – | – | yes |
| 231-525 | AT&T | WOLVERINE | – | yes | yes |
| 231-526 | AT&T | HARBOR SPG | – | – | yes |
| 231-527 | AT&T | BIG RAPIDS | – | yes | yes |
| 231-529 | Brightspeed | BRUTUS | – | yes | yes |
| 231-531 | T-Mobile | MUSKEGON | 2019-04-09 | yes | yes |
| 231-533 | Frontier | BELLAIRE | – | yes | yes |
| 231-534 | AT&T | TRAVERSECY | 2002-10-30 | yes | yes |
| 231-535 | AT&T | WALLOON LK | – | yes | yes |
| 231-536 | AT&T | EASTJORDAN | – | yes | yes |
| 231-537 | Brightspeed | LEVERING | – | – | yes |
| 231-538 | 123.NET, LLC | FREMONT | 2002-08-27 | yes | yes |
| 231-539 | AT&T | PELLSTON | – | yes | yes |
| 231-544 | Frontier | CENTRAL LK | – | yes | yes |
| 231-545 | Charter | BOYNEFALLS | 2016-09-23 | yes | yes |
| 231-546 | Brightspeed | ELMIRA | – | – | yes |
| 231-547 | AT&T | CHARLEVOIX | – | – | yes |
| 231-548 | Brightspeed | ALANSON | – | – | yes |
| 231-549 | Brightspeed | BOYNEFALLS | – | yes | yes |
| 231-550 | T-Mobile | PETOSKEY | 2021-09-22 | yes | yes |
| 231-552 | T-Mobile | CHARLEVOIX | 2025-07-31 | yes | yes |
| 231-557 | Verizon | MUSKEGON | – | – | yes |
| 231-559 | Bandwidth | MCBAIN | 2012-08-01 | yes | yes |
| 231-563 | AT&T | MUSKEGON | – | yes | yes |
| 231-564 | AT&T | KALKASKA | – | yes | yes |
| 231-566 | TON80 COMMUNICATIONS, LLC | HARRIETTA | 2022-02-22 | yes | yes |
| 231-567 | AT&T | MUSKEGON | 2020-12-02 | yes | yes |
| 231-568 | 123.NET, LLC | TRAVERSECY | – | – | yes |
| 231-569 | American Messaging | PETOSKEY | – | – | yes |
| 231-570 | AT&T | FIFE LAKE | 2002-03-29 | yes | yes |
| 231-571 | Frontier | MUSKEGON | – | yes | yes |
| 231-577 | Lumen | CADILLAC | 2002-05-14 | yes | yes |
| 231-578 | T-Mobile | MUSKEGON | – | yes | yes |
| 231-580 | T-Mobile | BIG RAPIDS | 2001-02-05 | yes | yes |
| 231-581 | Charter | ALBA | 2017-04-20 | yes | yes |
| 231-582 | AT&T | BOYNE CITY | – | – | yes |
| 231-583 | 123.NET, LLC | LUDINGTON | 2002-08-27 | yes | yes |
| 231-584 | PIGEON TEL. CO. | ALBA | – | – | yes |
| 231-585 | PIGEON TEL. CO. | LAKE NORTH | – | – | yes |
| 231-587 | AT&T | MANCELONA | – | yes | yes |
| 231-588 | Frontier | ELLSWORTH | – | yes | yes |
| 231-590 | Verizon | TRAVERSECY | – | – | yes |
| 231-591 | AT&T | BIG RAPIDS | – | – | yes |
| 231-592 | AT&T | BIG RAPIDS | – | – | yes |
| 231-593 | Spok | CADILLAC | – | – | yes |
| 231-594 | Twilio | HART | – | yes | yes |
| 231-596 | Spok | HARBOR SPG | – | – | yes |
| 231-597 | AT&T | CHEBOYGAN | – | yes | yes |
| 231-598 | AT&T | BIG RAPIDS | – | yes | yes |
| 231-599 | Frontier | EASTPORT | – | yes | yes |
| 231-600 | FRACTEL, LLC | TRAVERSECY | 2019-12-19 | yes | yes |
| 231-604 | Spok | KALKASKA | – | – | yes |
| 231-605 | Spok | NEWAYGO | – | – | yes |
| 231-608 | Spok | FRANKFORT | – | – | yes |
| 231-613 | AT&T | SCOTTVILLE | – | yes | yes |
| 231-614 | 123.NET, LLC | PENTWATER | – | – | yes |
| 231-615 | American Messaging | CHEBOYGAN | – | – | yes |
| 231-620 | AT&T | TRAVERSECY | – | – | yes |
| 231-622 | Lumen | PETOSKEY | 2002-08-19 | yes | yes |
| 231-624 | T-Mobile | KALKASKA | – | yes | yes |
| 231-625 | AT&T | CHEBOYGAN | – | yes | yes |
| 231-626 | Charter | LEVERING | 2012-09-26 | yes | yes |
| 231-627 | AT&T | CHEBOYGAN | – | yes | yes |
| 231-629 | T-Mobile | BIG RAPIDS | – | yes | yes |
| 231-631 | Verizon | TRAVERSECY | 2001-08-31 | – | yes |
| 231-632 | AT&T | TRAVERSECY | – | – | yes |
| 231-633 | AT&T | TRAVERSECY | – | – | yes |
| 231-634 | ISLAND TEL. CO. | BOIS BLANC | – | yes | yes |
| 231-635 | 123.NET, LLC | MACKINAWCY | 2002-08-27 | – | yes |
| 231-636 | 123.NET, LLC | HOWARDCITY | 2002-08-12 | yes | yes |
| 231-637 | INTERACTIVE SERVICES NETWORK, INC. | NORTHPORT | 2001-08-31 | – | yes |
| 231-638 | T-Mobile | MUSKEGON | 2001-03-09 | yes | yes |
| 231-639 | 123.NET, LLC | BEULAH | 2002-08-27 | – | yes |
| 231-640 | AT&T | LAKE ANN | 2002-08-30 | yes | yes |
| 231-642 | T-Mobile | TRAVERSECY | 2001-04-02 | yes | yes |
| 231-643 | 123.NET, LLC | MORLEY | 2002-08-27 | yes | yes |
| 231-645 | AT&T | TRAVERSECY | – | – | yes |
| 231-646 | Frontier | ELLSWORTH | 2001-06-18 | yes | yes |
| 231-647 | INTERACTIVE SERVICES NETWORK, INC. | CORAL | 2001-08-27 | – | yes |
| 231-648 | Lumen | HOWARDCITY | – | yes | yes |
| 231-649 | Verizon | TRAVERSECY | 2002-07-19 | – | yes |
| 231-651 | AT&T | BEULAH | 2002-08-30 | yes | yes |
| 231-652 | AT&T | NEWAYGO | – | yes | yes |
| 231-655 | Verizon | MANISTEE | 2014-12-19 | yes | yes |
| 231-656 | 123.NET, LLC | KALKASKA | 2002-08-27 | – | yes |
| 231-660 | 123.NET, LLC | BIG RAPIDS | 2002-08-27 | yes | yes |
| 231-663 | TON80 COMMUNICATIONS, LLC | MESICK | 2022-03-07 | yes | yes |
| 231-666 | Onvoy | MUSKEGON | 2017-10-09 | yes | yes |
| 231-667 | AT&T | MARION | 2002-08-30 | yes | yes |
| 231-668 | Lumen | TRAVERSECY | 2002-04-29 | yes | yes |
| 231-670 | Verizon | MUSKEGON | 2001-02-21 | yes | yes |
| 231-672 | AT&T | MUSKEGON | 2001-11-12 | yes | yes |
| 231-674 | Lumen | GRANT | 2001-05-18 | yes | yes |
| 231-675 | AT&T | BOYNE CITY | 2002-03-29 | – | yes |
| 231-676 | AT&T | BELLAIRE | 2002-08-30 | yes | yes |
| 231-678 | ACD TELECOM, INC. - MI | BRETHREN | 2005-01-19 | yes | yes |
| 231-679 | Verizon | BIG RAPIDS | 2002-10-24 | yes | yes |
| 231-680 | Lumen | REED CITY | 2002-08-19 | yes | yes |
| 231-681 | Frontier | FRUITPORT | 2001-06-18 | yes | yes |
| 231-682 | INTERACTIVE SERVICES NETWORK, INC. | ALDEN | 2002-04-22 | – | yes |
| 231-683 | Lumen | MUSKEGON | 2001-07-09 | yes | yes |
| 231-685 | Charter | RAVENNA | 2014-09-25 | yes | yes |
| 231-686 | 123.NET, LLC | FRANKFORT | 2002-08-27 | – | yes |
| 231-688 | FRACTEL, LLC | MERRITT | 2020-02-19 | yes | yes |
| 231-689 | AT&T | WHITECLOUD | – | yes | yes |
| 231-690 | Verizon | LUDINGTON | 2002-07-19 | – | yes |
| 231-695 | INTERACTIVE SERVICES NETWORK, INC. | HOWARDCITY | 2001-07-11 | – | yes |
| 231-699 | TON80 COMMUNICATIONS, LLC | FOUNTAIN | 2022-02-22 | yes | yes |
| 231-707 | Onvoy | NEWAYGO | 2016-02-25 | yes | yes |
| 231-709 | AT&T | TRAVERSECY | – | yes | yes |
| 231-712 | American Messaging | MUSKEGON | – | – | yes |
| 231-714 | Verizon | TRAVERSECY | – | yes | yes |
| 231-715 | AT&T | TRAVERSECY | – | yes | yes |
| 231-719 | Frontier | MUSKEGON | – | yes | yes |
| 231-720 | Frontier | MUSKEGON | – | yes | yes |
| 231-721 | 123.NET, LLC | HART | 2002-08-27 | yes | yes |
| 231-722 | Frontier | MUSKEGON | – | – | yes |
| 231-723 | AT&T | MANISTEE | – | – | yes |
| 231-724 | Frontier | MUSKEGON | – | yes | yes |
| 231-725 | Frontier | MUSKEGON | – | yes | yes |
| 231-726 | Frontier | MUSKEGON | – | yes | yes |
| 231-727 | Frontier | MUSKEGON | – | – | yes |
| 231-728 | Frontier | MUSKEGON | – | – | yes |
| 231-729 | AT&T | IRONS | 2002-08-30 | yes | yes |
| 231-730 | AT&T | MUSKEGON | – | – | yes |
| 231-731 | 123.NET, LLC | SHELBY | – | – | yes |
| 231-732 | Charter | MORLEY | – | yes | yes |
| 231-733 | Frontier | MUSKEGON | – | – | yes |
| 231-734 | AT&T | EVART | – | yes | yes |
| 231-735 | Verizon | TRAVERSECY | 2001-06-18 | yes | yes |
| 231-736 | Frontier | MUSKEGON | – | yes | yes |
| 231-737 | Frontier | MUSKEGON | – | – | yes |
| 231-739 | Frontier | MUSKEGON | – | – | yes |
| 231-740 | Verizon | MUSKEGON | – | – | yes |
| 231-742 | AT&T | HART | – | yes | yes |
| 231-743 | AT&T | MARION | – | yes | yes |
| 231-744 | Frontier | MUSKEGON | – | – | yes |
| 231-745 | AT&T | BALDWIN | – | yes | yes |
| 231-746 | TON80 COMMUNICATIONS, LLC | CHEBOYGAN | 2022-02-18 | yes | yes |
| 231-747 | Frontier | MUSKEGON | – | yes | yes |
| 231-750 | AT&T | MUSKEGON | – | – | yes |
| 231-751 | Onvoy | WALLOON LK | 2014-10-06 | yes | yes |
| 231-753 | Windstream | PETOSKEY | 2001-06-18 | yes | yes |
| 231-755 | Frontier | MUSKEGON | – | – | yes |
| 231-757 | AT&T | SCOTTVILLE | – | yes | yes |
| 231-758 | T-Mobile | PETOSKEY | – | yes | yes |
| 231-759 | Frontier | MUSKEGON | – | – | yes |
| 231-760 | Frontier | MUSKEGON | – | yes | yes |
| 231-762 | MICHIGAN CENTRAL BROADBAND COMPANY, LLC | AMBLE | – | – | yes |
| 231-763 | Charter | AMBLE | 2019-04-19 | yes | yes |
| 231-764 | INTERACTIVE SERVICES NETWORK, INC. | FIFE LAKE | 2001-08-31 | – | yes |
| 231-766 | Frontier | MUSKEGON | – | yes | yes |
| 231-767 | Frontier | MUSKEGON | – | yes | yes |
| 231-768 | AT&T | LE ROY | – | yes | yes |
| 231-769 | Frontier | MUSKEGON | – | yes | yes |
| 231-771 | Onvoy | ELK RAPIDS | 2016-03-22 | yes | yes |
| 231-772 | TON80 COMMUNICATIONS, LLC | WELLSTON | 2022-03-07 | yes | yes |
| 231-773 | Frontier | MUSKEGON | – | – | yes |
| 231-774 | ACD TELECOM, INC. - MI | INTERLOCHN | 2005-01-19 | yes | yes |
| 231-775 | AT&T | CADILLAC | – | – | yes |
| 231-776 | 123.NET, LLC | PETOSKEY | 2002-08-27 | – | yes |
| 231-777 | Frontier | MUSKEGON | – | – | yes |
| 231-778 | 123.NET, LLC | TRAVERSECY | 2002-08-27 | – | yes |
| 231-779 | AT&T | CADILLAC | – | – | yes |
| 231-780 | Frontier | MUSKEGON | – | yes | yes |
| 231-782 | 123.NET, LLC | CHEBOYGAN | 2002-08-27 | – | yes |
| 231-786 | FRACTEL, LLC | TRAVERSECY | 2021-03-24 | yes | yes |
| 231-787 | Onvoy | WHITECLOUD | 2014-11-07 | yes | yes |
| 231-788 | Frontier | MUSKEGON | – | yes | yes |
| 231-790 | Windstream | FREESOIL | 2001-06-18 | yes | yes |
| 231-791 | Windstream | REED CITY | 2001-05-18 | yes | yes |
| 231-792 | 123.NET, LLC | MANCELONA | 2002-08-27 | – | yes |
| 231-793 | AT&T | WHITECLOUD | – | yes | yes |
| 231-794 | AT&T | MANISTEE | 2002-08-30 | yes | yes |
| 231-796 | AT&T | BIG RAPIDS | – | – | yes |
| 231-797 | AT&T | LUTHER | – | yes | yes |
| 231-798 | Frontier | MUSKEGON | – | yes | yes |
| 231-799 | Frontier | MUSKEGON | – | yes | yes |
| 231-800 | Onvoy | LUTHER | 2017-10-02 | yes | yes |
| 231-803 | Lumen | MORLEY | 2001-05-18 | yes | yes |
| 231-805 | ACD TELECOM, INC. - MI | KALEVA | 2005-01-19 | yes | yes |
| 231-806 | 123.NET, LLC | CORAL | 2002-08-27 | – | yes |
| 231-808 | 123.NET, LLC | CENTRAL LK | 2002-08-12 | – | yes |
| 231-813 | 123.NET, LLC | LUDINGTON | – | – | yes |
| 231-818 | AT&T | CHEBOYGAN | – | yes | yes |
| 231-819 | Onvoy | TUSTIN | 2014-10-06 | yes | yes |
| 231-821 | Frontier | HOLTON | – | yes | yes |
| 231-822 | INTERACTIVE SERVICES NETWORK, INC. | BEULAH | 2001-08-27 | – | yes |
| 231-823 | Frontier | STANWOOD | – | yes | yes |
| 231-824 | AT&T | MANTON | – | yes | yes |
| 231-825 | AT&T | MCBAIN | – | yes | yes |
| 231-826 | Brightspeed | FALMOUTH | – | yes | yes |
| 231-828 | Frontier | TWIN LAKE | – | yes | yes |
| 231-829 | AT&T | TUSTIN | – | yes | yes |
| 231-830 | Frontier | MUSKEGON | – | yes | yes |
| 231-831 | Onvoy | EASTJORDAN | – | yes | yes |
| 231-832 | AT&T | REED CITY | – | – | yes |
| 231-833 | AT&T | WOLVERINE | 2005-04-11 | yes | yes |
| 231-834 | AT&T | GRANT | – | yes | yes |
| 231-835 | AT&T | GLEN LAKE | 2002-08-30 | yes | yes |
| 231-836 | 123.NET, LLC | EVART | 2002-08-27 | – | yes |
| 231-837 | American Messaging | FREMONT | – | – | yes |
| 231-838 | AT&T | PETOSKEY | 2002-03-29 | – | yes |
| 231-839 | Brightspeed | LAKE CITY | – | – | yes |
| 231-842 | 123.NET, LLC | CADILLAC | 2002-08-27 | – | yes |
| 231-843 | Frontier | LUDINGTON | – | – | yes |
| 231-844 | Lumen | INDIAN RIV | 2001-06-18 | yes | yes |
| 231-845 | Frontier | LUDINGTON | – | – | yes |
| 231-846 | T-Mobile | CADILLAC | – | yes | yes |
| 231-848 | KALEVA TEL. CO. | WELLSTON | – | – | yes |
| 231-852 | AT&T | LUDINGTON | – | yes | yes |
| 231-853 | Frontier | RAVENNA | – | yes | yes |
| 231-854 | Frontier | HESPERIA | – | – | yes |
| 231-855 | AT&T | MUSKEGON | – | yes | yes |
| 231-856 | AT&T | MORLEY | – | yes | yes |
| 231-859 | KALEVA TEL. CO. | DUBLIN | – | – | yes |
| 231-861 | Frontier | SHELBY | – | yes | yes |
| 231-862 | ACE TEL. CO. OF MICHIGAN, INC. | HOXEYVILLE | – | yes | yes |
| 231-864 | Brightspeed | BEAR LAKE | – | – | yes |
| 231-865 | Frontier | FRUITPORT | – | yes | yes |
| 231-866 | AT&T | SUTTONSBAY | 2002-08-30 | yes | yes |
| 231-867 | Brightspeed | CHIPPEWALK | – | yes | yes |
| 231-869 | Frontier | PENTWATER | – | yes | yes |
| 231-871 | AT&T | BEULAH | – | yes | yes |
| 231-872 | AT&T | REED CITY | – | yes | yes |
| 231-873 | Frontier | HART | – | – | yes |
| 231-874 | 123.NET, LLC | WOLVERINE | 2002-08-27 | – | yes |
| 231-875 | Bandwidth | FRUITPORT | – | yes | yes |
| 231-876 | AT&T | CADILLAC | – | yes | yes |
| 231-877 | 123.NET, LLC | NORTHPORT | – | – | yes |
| 231-878 | Verizon | CADILLAC | 2002-07-19 | – | yes |
| 231-879 | AT&T | FIFE LAKE | – | yes | yes |
| 231-880 | SKYE TELECOM LLC DBA SKYETEL | MUSKEGON | 2021-09-08 | yes | yes |
| 231-881 | AT&T | PETOSKEY | – | yes | yes |
| 231-882 | AT&T | BEULAH | – | yes | yes |
| 231-883 | AT&T | TRAVERSECY | – | – | yes |
| 231-884 | AT&T | CADILLAC | – | yes | yes |
| 231-885 | ACE TEL. CO. OF MICHIGAN, INC. | MESICK | – | yes | yes |
| 231-886 | AT&T | KALKASKA | – | yes | yes |
| 231-887 | AT&T | MANISTEE | – | yes | yes |
| 231-888 | Onvoy | TWIN LAKE | 2015-06-16 | yes | yes |
| 231-889 | AT&T | ONEKAMA | – | yes | yes |
| 231-890 | AT&T | TRAVERSECY | – | – | yes |
| 231-893 | Frontier | WHITEHALL | – | – | yes |
| 231-894 | Frontier | WHITEHALL | – | yes | yes |
| 231-898 | CARR TEL. CO. | CARR | – | yes | yes |
| 231-899 | 123.NET, LLC | NORTHPORT | 2002-08-27 | – | yes |
| 231-900 | FRACTEL, LLC | MUSKEGON | 2019-05-13 | yes | yes |
| 231-902 | INTERACTIVE SERVICES NETWORK, INC. | HART | 2001-08-27 | – | yes |
| 231-903 | Lumen | MUSKEGON | 2002-04-29 | yes | yes |
| 231-907 | AT&T | LUDINGTON | 2002-09-03 | yes | yes |
| 231-908 | 123.NET, LLC | MCBAIN | 2002-08-27 | – | yes |
| 231-912 | AT&T | REED CITY | 2002-08-30 | yes | yes |
| 231-916 | Lumen | MANCELONA | 2001-06-18 | yes | yes |
| 231-920 | AT&T | CADILLAC | – | – | yes |
| 231-922 | AT&T | TRAVERSECY | – | – | yes |
| 231-923 | T-Mobile | HART | 2001-05-18 | yes | yes |
| 231-924 | AT&T | FREMONT | – | – | yes |
| 231-925 | 123.NET, LLC | SCOTTVILLE | 2002-08-27 | yes | yes |
| 231-928 | AT&T | FREMONT | – | yes | yes |
| 231-929 | AT&T | TRAVERSECY | – | – | yes |
| 231-930 | ACD TELECOM, INC. - MI | BEULAH | 2001-06-18 | yes | yes |
| 231-932 | AT&T | TRAVERSECY | – | – | yes |
| 231-933 | AT&T | TRAVERSECY | – | – | yes |
| 231-935 | AT&T | TRAVERSECY | – | – | yes |
| 231-936 | Windstream | SCOTTVILLE | 2001-06-18 | yes | yes |
| 231-937 | Frontier | HOWARDCITY | – | yes | yes |
| 231-938 | AT&T | TRAVERSECY | – | yes | yes |
| 231-939 | AT&T | PETOSKEY | 2017-08-09 | yes | yes |
| 231-941 | AT&T | TRAVERSECY | – | – | yes |
| 231-942 | Verizon | CADILLAC | 2001-06-18 | yes | yes |
| 231-943 | AT&T | TRAVERSECY | – | yes | yes |
| 231-944 | CYNERGYCOMM.NET, INC. - MI | TRAVERSECY | – | yes | yes |
| 231-946 | AT&T | TRAVERSECY | – | – | yes |
| 231-947 | AT&T | TRAVERSECY | – | – | yes |
| 231-955 | AT&T | MUSKEGON | – | yes | yes |
| 231-963 | TON80 COMMUNICATIONS, LLC | MCBAIN | 2022-02-28 | yes | yes |
| 231-966 | TON80 COMMUNICATIONS, LLC | FREESOIL | 2022-02-22 | yes | yes |
| 231-968 | Bandwidth | CADILLAC | 2021-09-16 | yes | yes |
| 231-970 | AT&T | BEAR LAKE | 2002-08-30 | yes | yes |
| 231-972 | Brightspeed | MECOSTA | – | – | yes |
| 231-974 | 123.NET, LLC | GRANT | 2002-08-27 | yes | yes |
| 231-977 | FRACTEL, LLC | MACKINAWCY | 2020-02-19 | yes | yes |
| 231-981 | Frontier | WHITEHALL | – | yes | yes |
| 231-994 | ACD TELECOM, INC. - MI | LKLEELANAU | 2005-01-19 | yes | yes |
| 231-995 | AT&T | TRAVERSECY | – | – | yes |
| 231-999 | Onvoy | CENTRAL LK | 2015-08-24 | yes | yes |
Frequently asked
How many prefixes does area code 231 have?
572 NXX blocks are assigned of 786 possible. Each block is 10,000 consecutive numbers, so the code currently covers about 5,720 thousand-number ranges across 99 rate centers.
What do the first three digits after 231 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 231 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 231 table?
That the block is in thousands-block pooling: carriers draw 1,000-number lots from it instead of taking all 10,000. 382 of 231'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.
More about this code: overview · carriers · spam complaints · local time