557 Area CodeSt. Louis, MO
Area code 557 covers St. Louis and nearby communities in Missouri, in the Central Time (CT) zone, home to about 1 million people across 91 cities. It overlays 314, so the same region uses both and every local call needs all ten digits.
Overview
- Major City
- St. Louis
- State
- Missouri (MO)
- Timezone
- Central Time (CT)
- Current Time
- Overlay
- Yes – shares area with 314
Where is area code 557?
Area code 557 serves part of St. Louis, MO and the surrounding areas. It has a single overlay (314) that serves the same area.
Overview of the 557 Area Code
What is the 557 area code?
The 557 area code serves St. Louis, Missouri, alongside other established area codes. When you see a 557 number, it indicates a local number within this geographic area.
Why was area code 557 created?
The 557 area code was introduced as an overlay to add numbers in St. Louis once the existing area code 314 began to run out of available prefixes. It added a new supply of numbers without requiring current residents to change their existing digits.
Geographic Coverage of the 557 Area Code
The 557 area code serves St. Louis and surrounding areas in Missouri. It operates within the Central Time (CT) time zone. It complements the coverage of area code 314. This area code covers several key cities, including:
- St. Louis
- Florissant
- Chesterfield
- Oakville
- University City
- Kirkwood
Got a call from a 557 number? It came from St. Louis, MO. Since 557 overlays with 314, every local call in the region needs all ten digits to land on the right line. Inside 557, St. Louis holds about 28% of the population; the rest is split across 90 smaller cities.
St. Louis Area Codes Overview
St. Louis is served by multiple area codes, reflecting its telecommunications needs. The 557 area code operates alongside 314. Here are the area codes serving this region:
The introduction of the 557 area code helped prevent number exhaustion, ensuring a continuous supply of phone numbers across the geographic area.
What cities does area code 557 cover?
| City | State | Population | % of Area Code | % of City |
|---|---|---|---|---|
| St. Louis | MO | 279,695 | 16% | 100% |
| Florissant | MO | 51,290 | 3% | 100% |
| Chesterfield | MO | 49,465 | 2% | 21% |
| Oakville | MO | 36,143 | 4% | 99% |
| University City | MO | 34,349 | 1% | 100% |
| Kirkwood | MO | 29,348 | 2% | 99% |
| Mehlville | MO | 28,380 | 2% | 100% |
| Maryland Heights | MO | 27,671 | 6% | 100% |
| Hazelwood | MO | 24,951 | 4% | 100% |
| Webster Groves | MO | 23,525 | 1% | 100% |
* Sources: Population – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). Area code assignments – NANPA CO Code data. See our data methodology.
Has area code 557 been reported for unwanted calls?
Yes – 7 unwanted-call complaints were reported to the FTC for numbers showing a 557 area code (Jun 9 – Jun 29, 2026).
- 14% robocalls
- ↑ 150% vs prior period
Most-reported subjects
- Vacation & timeshares57%4
- Calls pretending to be government, businesses, or family and friends14%1
- Medical & prescriptions14%1
* Caller ID is easily spoofed, so these figures reflect the number shown on caller ID, not the caller's true location – an area code alone never identifies a caller. The FTC does not verify the facts in these complaints. Source: FTC Do Not Call (DNC) Reported Calls Data, retrieved 2026-07-05.
Which prefixes and exchanges belong to area code 557?
2% assigned to a telco
- 100% Landline
- 0% Wireless
- 0% Unknown
| Prefix | Usage | Carrier |
|---|---|---|
| (557)200- | Landline | Onvoy |
| (557)201- | Landline | Teleport Communications America |
| (557)202- | Landline | Comcast Ip Phone |
| (557)273- | Landline | Teleport Communications America |
| (557)362- | Landline | Teleport Communications America |
| (557)454- | Landline | Teleport Communications America |
| (557)467- | Landline | Onvoy |
| (557)500- | Landline | Onvoy Spectrum |
| (557)653- | Landline | Teleport Communications America |
| (557)747- | Landline | Teleport Communications America |
Frequently Asked Questions about the 557 Area Code
Who called me from a 557 number?
A 557 number is assigned to St. Louis, Missouri, so a call may come from there. But caller ID is easy to fake, and scammers often spoof a local 557 code to look nearby, so a 557 number doesn't prove the caller is local. Recently, 7 unwanted-call complaints were reported to the FTC for numbers showing the 557 code (14% flagged as robocalls). If you don't recognize the number, let it go to voicemail; a real caller will leave a message.
Is 557 a scam area code?
No area code is a scam on its own. 557 is a normal, officially assigned code for St. Louis, Missouri. Spam callers spoof local codes to raise the odds you answer, so 557 on your caller ID says nothing about who is really calling. Recently, 7 unwanted-call complaints were reported to the FTC for numbers showing the 557 code (14% flagged as robocalls). Judge the call itself, not the area code.
Why do I keep getting calls from the 557 area code?
Repeated calls from different 557 numbers are usually spoofing: a robocaller rotates through 557 numbers so each call looks local and slips past simple blocks. Recently, 7 unwanted-call complaints were reported to the FTC for numbers showing the 557 code (14% flagged as robocalls). Blocking one number rarely helps; voicemail screening, your carrier spam filter, and the Do Not Call Registry work better.
Should I answer an unknown 557 number?
If you aren't expecting a 557 call, let it ring to voicemail. Legitimate callers leave a message, most robocallers hang up when no one picks up, and answering can mark your number as active and bring more calls.
How do I block calls from the 557 area code?
Block a single 557 number from your recent-calls list (iPhone: tap the number, then Block this Caller; Android: tap the number, then Block or report spam). To cut the volume, turn on Silence Unknown Callers on iPhone or spam protection on Android, enable spam filtering from your carrier, and register at DoNotCall.gov. Blocking the entire 557 code also stops legitimate local calls, so use it only as a last resort.
Where is area code 557?
Area code 557 covers St. Louis and the surrounding area in Missouri, spanning 91 cities with about 1,006,619 residents. It shares its area with overlay code 314.
Is 557 a real area code?
Yes. 557 is an active code in the North American Numbering Plan, assigned by NANPA and in service for St. Louis, Missouri. A real code can still show up on spoofed spam calls, so treat unknown 557 calls with normal caution.
What timezone is the 557 area code in?
The 557 area code is in the Central Time (CT). Because a number can be kept when someone moves or switches to VoIP, a specific 557 caller may not be in that zone.
How do I call a 557 number from abroad?
From outside the US, dial your country's exit code, then 1 (the US country code), then 557 and the seven-digit number. From a mobile phone you can usually just enter +1 557 followed by the number and let the phone add the exit code for you.