Phone numbers in Washington, Iowa
Washington has 10 phone prefixes in area code 319.
Biggest holders: Windstream Iowa Communications, Inc. - North, Verizon Wireless, UScellular. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 50%
- Local phone company 40%
- Phone company 10%
Every prefix in Washington
Search the first six digits of a number in this list. If it's here, the number started in Washington with the carrier shown. If it isn't, check the Iowa page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 319-458 | Verizon Wireless | Mobile carrier | – |
| 319-460 | Verizon Wireless | Mobile carrier | – |
| 319-461 | UScellular | Mobile carrier | – |
| 319-548 | T-Mobile (including Sprint) | Mobile carrier | – |
| 319-591 | UScellular | Mobile carrier | – |
| 319-598 | Local Telephone Data Services | Phone company | 2001 |
| 319-653 | Windstream Iowa Communications, Inc. - North | Local phone company | – |
| 319-789 | Windstream Iowa Communications, Inc. - North | Local phone company | 2015 |
| 319-863 | Windstream Iowa Communications, Inc. - North | Local phone company | – |
| 319-864 | Kalona Cooperative Telephone | Local phone company | 2017 |
Most prefixes are pooled: the 10,000 numbers in each are handed out in blocks of 1,000 to different carriers, and people can also take their numbers to another carrier. So the carrier shown is where the prefix started, not a guarantee about any one number. Source: NANPA central office code records, 2026-10-10.