MEHLVILLE prefixes in area code 557
NANPA records 5 assigned NXX blocks to rate center MEHLVILLE in area code 557, 6.0% of the 84 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 3 holders hold those blocks, the largest being T-MOBILE USA, INC. (2), ONVOY, LLC - MO (2), NEW CINGULAR WIRELESS PCS, LLC - IL (1). The earliest assignment on record here is 2023-05-19 and the most recent 2026-05-29. 5 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots. The same rate center name also appears in area code 314 – overlay codes cover the same geography, so a rate center is served by all of them.
Prefixes assigned here
| Prefix | Holder of record | Assigned | Pooled | In service |
|---|---|---|---|---|
| 557-203 | T-Mobile T-MOBILE USA, INC. | 2023-05-19 | yes | yes |
| 557-212 | T-Mobile T-MOBILE USA, INC. | 2023-09-29 | yes | yes |
| 557-221 | Onvoy ONVOY, LLC - MO | 2024-04-10 | yes | yes |
| 557-247 | AT&T NEW CINGULAR WIRELESS PCS, LLC - IL | 2025-12-11 | yes | yes |
| 557-256 | Onvoy ONVOY, LLC - MO | 2026-05-29 | yes | yes |
The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.
Who holds the blocks
| Holder | Brand | Blocks | Share here |
|---|---|---|---|
| T-MOBILE USA, INC. | T-Mobile | 2 | 40% |
| ONVOY, LLC - MO | Onvoy | 2 | 40% |
| NEW CINGULAR WIRELESS PCS, LLC - IL | AT&T | 1 | 20% |
Same rate center in other codes
Overlay codes cover the same geography, so one rate center is served by all of them.
Frequently asked
Which prefixes belong to MEHLVILLE in area code 557?
5 blocks: 203, 212, 221, 247, 256. The table above gives the holder of each.
Which carriers have numbers in MEHLVILLE?
T-MOBILE USA, INC. (2 blocks), ONVOY, LLC - MO (2 blocks), NEW CINGULAR WIRELESS PCS, LLC - IL (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.
Is MEHLVILLE a city?
It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.