Where is area code 557?
NANPA assigns 557 to Missouri. The source report does not provide city-level coverage for this record, so this page does not guess a particular city. Browse other codes in Missouri
Verified area-code information
557 Area Code
557 is an in-service United States area code assigned to Missouri. It identifies a numbering region, not a caller’s current location.
Official Numbering RegionVerified NANPA Assignment
MissouriArea Code 557
Country: United States•Time Zone: Central•Overlays: 314•In Service: 12-Aug-2022
- Numbering country
- United States
- Area-code type
- Geographic
- Numbering region
- Missouri
- Time-zone information
- Central
- In service since
- 12-Aug-2022
View the official area-code maps ↗. Maps show numbering areas, not a caller’s location.
Time zones associated with 557
NANPA lists Central for this numbering area. These are numbering-region time zones, not a caller’s current location.
Central time
An area code can span more than one time zone. Local daylight-saving rules may differ.
What area codes overlay 557?
The NANPA source lists 314 in the same overlay complex. An overlay can serve the same broad numbering area; individual numbers still do not prove where a person is.
How do you dial a 557 number?
Use the North American country calling code +1 followed by the three-digit area code and seven-digit local number. For example, write the pattern as +1 557 XXX XXXX. Local dialing rules and charges depend on your location and provider. Check a supported dialing format or check NANPA’s 10-digit dialing list.
Assigned prefixes in 557
NANPA’s US report listed 69 assigned prefixes on 2026-09-29. These are code assignments, not a count of active phone numbers or proof of a caller’s current carrier. Search any US area code and prefix.
Top rate-center labels by assigned prefixes
| Rate center | Assigned prefixes |
|---|---|
| ST LOUIS | 31 |
| LADUE | 14 |
| KIRKWOOD | 10 |
| CREVECOEUR | 5 |
| MEHLVILLE | 4 |
Top listed companies by assigned prefixes
| Assignment company | Assigned prefixes |
|---|---|
| NEW CINGULAR WIRELESS PCS, LLC - IL | 17 |
| TELEPORT COMMUNICATIONS AMERICA, LLC - MO | 15 |
| ONVOY, LLC - MO | 13 |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MO | 7 |
| ONVOY SPECTRUM, LLC | 3 |
557 prefix lookup
69 assigned prefixes are listed for this area code. Search NANPA’s US central-office code assignments. The listed company and rate center describe an assignment; number portability means they cannot identify the current carrier, subscriber, or caller.
The area-code file loads when you search. The three-digit prefix stays in your browser.
Check a number with area code 557
Enter the full ten-digit number to see its structure and formatting. The check stays in your browser.
Check a 557 number
Enter a 10-digit +1 North American number. We check its structure and area-code record, not the caller’s identity or whether the line is active.
Processed locally in your browser. Nothing you enter is sent to OfficialAreaCode or saved.
Received an unfamiliar call?
The displayed number may be spoofed. Do not rely on an area code as proof of caller identity. If the caller claims to represent a business, end the call and contact that business using a number you found independently.
Common questions about 557
What time zone is area code 557 in?
557 is assigned to Missouri, and the NANPA record associates it with Central time. A phone number does not reveal its owner’s current time zone. The clock above uses a representative time zone for the numbering area.
Does 557 mean the caller is in Missouri?
No. An area code is an assignment, and a person can travel, move, use internet calling, or display a spoofed number.
Can this page identify who called?
No. OfficialAreaCode has no live subscriber directory or spam-report database.