Quick answer
The 557 area code serves St. Louis, Missouri in the Central Time (CT) (UTC-6 / UTC-5 DST). Assigned in 2022, it covers St. Louis City and Inner Suburbs including St. Louis, Clayton, University City. Overlay code: 314.
- Region
- St. Louis City and Inner Suburbs, MO
- Time zone
- CT (UTC-6)
- Assigned
- 2022
- Population
- ~1,000,000
- Local time now
- · live
What is the area code for St. Louis?
The area code for St. Louis, Missouri is 557, with overlay code 314 sharing the same geographic footprint. The 557 area code is a North American Numbering Plan geographic code assigned in 2022, covering the St. Louis City and Inner Suburbs region. It serves approximately 1,000,000 residents on the Central Time (CT) (UTC-6 / UTC-5 DST).
All St. Louis area codes
St. Louis is served by 2 area codes across the metro area. 557 is the 2022 addition; the others were added as overlays or for surrounding suburbs.
- 314 — St. Louis — 1947 original
- 557 (current page) — Overlay on the same metro, assigned 2022
Cities served by the 557 area code
The 557 area code covers 5 major cities and towns across the St. Louis City and Inner Suburbs region (MO):
Businesses across St. Louis and surrounding cities use 557 numbers to project local presence and lift call answer rates. Industry studies of local presence dialing consistently report answer-rate gains of 20–40% over toll-free or out-of-area numbers — a caller ID that matches the recipient's region looks familiar and gets picked up.
557 area code time zone and business hours
The 557 area code is in the Central Time (CT) zone (UTC-6 / UTC-5 DST). Standard business hours in 557 run 9 AM to 5 PM CT.
If you're calling into 557 from a different time zone, factor in the offset. For example, an Eastern Time business calling 557 at 9 AM ET reaches St. Louis at 8 AM CT — likely outside standard business hours.
History of the 557 area code
The 557 area code was introduced in 2022 when the North American Numbering Plan was first deployed. As St. Louis grew and number demand increased, overlay code 314 was added to serve the same geographic region — a common solution that avoids forcing existing subscribers to change their numbers.
- 1947 314 added to serve the same region
- 2022 557 entered service
Is the 557 area code safe? Spam and scam calls
557 is a legitimate geographic area code for St. Louis — it is not a scam code or a premium-rate prefix, and a call from a 557 number is most likely a genuine local caller. The risk is not the area code itself but a tactic called neighbor spoofing: scammers fake their caller ID so an unwanted call appears to come from your own area code, because people answer familiar numbers more readily.
If you get an unexpected 557 call, a few signals point to a likely scam — a pre-recorded message, urgent pressure to act now, a demand for payment by gift card or wire transfer, or anyone asking for passwords, Social Security, or account numbers. Let suspicious calls go to voicemail, never share personal information, and report fraud to the FTC at reportfraud.ftc.gov. The FCC consumer guide on spoofing explains your rights under the Truth in Caller ID Act. A real St. Louis business will leave a clear voicemail and will not pressure you.
US carriers verify caller ID with the STIR/SHAKEN framework, which flags many spoofed numbers as "Spam Likely" before they ring. DialPhone 557 numbers are registered for STIR/SHAKEN attestation, so calls from your business are verified as genuine and reach customers without a false spam label. See the DialPhone guide to VoIP security for more.
Why get a 557 area code number for your business?
Getting a 557 number gives your business three measurable advantages over a toll-free or out-of-area number:
- Local trust signal. Customers in St. Louis recognize 557 as their home area code. Caller ID matching builds immediate credibility for service businesses, sales outreach, and patient communication.
- Higher answer rate. Calls from a familiar local area code are answered far more often than unknown or toll-free numbers — industry measurements of local presence dialing put the lift at 20–40%, which matters most for outbound sales, appointment confirmations, and time-sensitive service callbacks.
- Targeted marketing. Businesses serving St. Louis and the broader St. Louis City and Inner Suburbs can advertise a local number across print, radio, billboards, and digital channels for higher conversion than a national 800 number.
For businesses in St. Louis and surrounding cities, top industries that benefit from local 557 presence include Professional Services, Healthcare, and Retail. DialPhone's AI receptionist is available for every 557 number — never miss a call, even after standard business hours.
How to get a 557 area code number
Setting up a 557 business number with DialPhone takes under 10 minutes:
- Sign up for a DialPhone plan. Choose any plan starting at $24/user/month. Free 14-day trial, no credit card required.
- Search available 557 numbers. Filter the DialPhone number inventory by area code, city, or pattern.
- Choose your number and configure. Assign your new 557 number to a user or team, set up call routing, voicemail, AI receptionist, and business SMS.
- Port your existing number (optional). Already have a 557 number? Free number porting in 2 to 5 business days with zero service interruption.
New to local numbers? The complete guide to getting a local phone number covers choosing the right area code, porting an existing line, and avoiding spam flags.
557 area code overlay codes
The St. Louis City and Inner Suburbs region is served by multiple overlay area codes:
| Area Code | Coverage |
|---|---|
| 557 | Primary area code for St. Louis City and Inner Suburbs, assigned 2022 |
| 314 | Overlay — same geography (assigned 1947) |
All overlay codes serve the same St. Louis region. New subscribers may be assigned any available code; existing numbers retain their original prefix.
AI receptionist for 557 area code businesses
Every DialPhone 557 number includes optional AI receptionist coverage, available 24/7. The AI handles calls when your team is unavailable — answering common questions, booking appointments, routing urgent callers to on-call staff, and capturing voicemail with full transcription and intent tagging.
For businesses in St. Louis that handle high call volume, run extended hours, or need bilingual support (especially valuable in service areas with diverse customer bases), the AI receptionist reduces voicemail backlog and improves first-call resolution.
All area codes in Missouri
Missouri has 9 active geographic area codes. The 557 area code is part of the same numbering plan as the codes listed below — calls between them are typically local within the state, depending on the carrier.
Nearby area codes
Related area codes in Missouri and the Central Time (CT) region:
- 314 area code — St. Louis, Missouri
- 417 area code — Springfield, Missouri
- 573 area code — Columbia, Missouri
- 636 area code — St. Peters, Missouri
- 660 area code — Sedalia, Missouri
- 816 area code — Kansas City, Missouri
All Missouri area codes → · Browse all US area codes →
More area codes: ← 551 Jersey City · 559 Fresno →
How We Tested
DialPhone re-verifies every area code page every 90 days. Area code geography, timezone, and overlay data come from the official North American Numbering Plan Administration (NANPA) database. Pricing reflects the published DialPhone plan tiers — see the pricing page for current details. Number availability varies; check the DialPhone signup flow for live inventory in the 557 region.
What We Don't Like
- Number availability is finite. Popular St. Louis area codes can be inventory-constrained — request specific vanity patterns early.
- Porting timing varies. Most 557 ports complete in 2-5 business days; complex multi-line legacy contracts can take 7-10.
- HIPAA tier required for healthcare. The Core $24 plan doesn't include a BAA — healthcare users need Advanced ($34) or above.