CallataGuidesGet a local business phone number in Eureka, MO
Eureka's area code, prefixes and carriers from NANPA records, and how to put a Eureka number in front of your customers.
- Area code
- 636
- Exchanges
- 6NANPA-assigned
- Carriers
- 4
- Population
- 13,277Census 2024 est.
Eureka area codes
With 13,277 residents in the Census 2024 estimate, Eureka sits in St. Louis County, Missouri. All 6 exchanges NANPA lists for its rate center are in area code 636. Eureka is in the Central time zone.
According to NANPA's dialing-plan data, local calls within 636 are dialed as seven digits and toll calls as 1 plus ten digits.
| Area code | Exchanges here | Share | In service since | Overlay with | Time zone |
|---|---|---|---|---|---|
| 636 | 6 | 100% | 1999 | none | Central |
Source: NANPA utilized central office code file and NPA report, dated 10/01/2026.
Who holds Eureka phone exchanges
4 carriers hold the 6 exchanges assigned to Eureka's rate center. Onvoy, LLC - Mo has the most, with 2. 6 of them are pooled codes, which the holder shares with other carriers in blocks of 1,000 numbers. A business number in Eureka can come from any of these blocks; once it is yours, porting lets it move between providers.
| Carrier (NANPA operating company) | Exchanges | Share |
|---|---|---|
| Onvoy, LLC - Mo | 2 | 33% |
| Southwestern Bell | 2 | 33% |
| Peerless Network of Missouri, LLC - Mo | 1 | 17% |
| Paetec Itel, LLC | 1 | 17% |
Carrier names are the operating company (OCN) names on NANPA's utilized central office code file dated 10/01/2026. A carrier holding a code may port numbers to other carriers.
Eureka phone prefixes
These are the central office codes NANPA records for Eureka. A caller seeing one of them recognizes a local number. The earliest assignment date recorded in the file for these codes is 2013. 2 of the 6 were assigned in 2020 or later.
| Area code | Prefixes (NXX) |
|---|---|
| 636 | 280, 429, 494, 549, 587, 938 |
Source: NANPA utilized central office code file.
When Eureka's exchanges were assigned
The table groups Eureka's exchanges by the decade NANPA recorded them as assigned.
| Decade assigned | Exchanges | Share |
|---|---|---|
| 2010s | 1 | 33% |
| 2020s | 2 | 67% |
Assignment dates as recorded in NANPA's utilized code file; codes without a recorded date are excluded.
What makes a number local to Eureka
What a caller sees as "local" is the area code plus prefix. In Eureka, those come from the EUREKA rate center, as recorded by NANPA.
If your business already has a Eureka number, porting it to Callata is free and keeps it on your cards, listings and vehicles.
The local business market
Eureka is part of the St. Louis, MO-IL metro area, home to 2.8 million people in 2024. County Business Patterns counted 69,470 business establishments in the St. Louis, MO-IL metro area in 2023, employing 1,263,674 people. The largest sectors by establishment count are health care and social assistance (10,427), retail trade (8,095), and professional, scientific, and technical services (7,057).
| Industry | Establishments | Employees | Employees per establishment |
|---|---|---|---|
| Limited-service restaurants | 2,334 | 45,289 | 19.4 |
| Full-service restaurants | 2,019 | 49,930 | 24.7 |
| Agencies providing services for the elderly and persons with disabilities | 1,898 | 16,546 | 8.7 |
| Physician practices | 1,785 | 22,126 | 12.4 |
| Insurance agencies and brokerages | 1,509 | 7,839 | 5.2 |
| Law offices | 1,393 | 10,509 | 7.5 |
| Offices of real estate agents and brokers | 1,099 | 2,523 | 2.3 |
| Landscaping services | 1,092 | 7,504 | 6.9 |
Selected small-business industries (six-digit NAICS) covered by these guides. Source: Census County Business Patterns 2023.
A Eureka number on Callata
Callata Office costs $99 per month for up to 5 people, and each additional user is $20 a month. That covers up to 3 local numbers, calling from a browser or your cell, transcribed voicemail, recorded calls with AI summaries, after-hours routing and E911 on each number.
Porting a number you already use in Eureka is free, and business texting is available once the carrier registration (10DLC) is approved; the registration carries a one-time $49 fee. Which specific numbers are open in a given area code depends on carrier inventory at the time you sign up.
AI agents are optional: an AI receptionist or scheduler can pick up when the team is busy or closed, take a message, send a text or email, or transfer the call. They draw on prepaid AI minutes ($0.25/minute), disclose that they are AI, and outbound AI calls require prior consent and are limited to 8am–9pm.
An 18-person team is the benchmark here, the rounded average establishment size in the St. Louis, MO-IL metro area. Billed per seat at month-to-month list prices (checked September 28, 2026), RingCentral RingEX Core costs $540.00 a month and Ooma Office Pro $449.10. Callata comes to $359.00 a month for 18 users ($99 a month with 5 users included, then $20 per additional user), below both.
| Provider (plan) | Pricing basis | Per month | Per year |
|---|---|---|---|
| Callata (Callata Office) | $99 incl. 5 users, $20 per extra user | $359.00 | $4,308.00 |
| Quo (Starter) | $19.00 per user | $342.00 | $4,104.00 |
| Nextiva (Core) | $23.00 per user | $414.00 | $4,968.00 |
| Ooma (Office Pro) | $24.95 per user | $449.10 | $5,389.20 |
| Dialpad (Standard) | $27.00 per user | $486.00 | $5,832.00 |
| RingCentral (RingEX Core) | $30.00 per user | $540.00 | $6,480.00 |
Competitor prices are each vendor's published month-to-month list price per user for its lowest plan that includes business calling and texting, checked September 28, 2026: Quo Starter $19, Nextiva Core $23, Ooma Office Pro $24.95 (Essentials excludes texting; one-time $29.95 activation not included), Dialpad Standard $27, RingCentral RingEX Core $30 ($20 billed annually). Prices exclude taxes and fees and may change; annual contracts lower some competitors' prices.
Frequently asked questions
What area code is Eureka, MO?
636. All exchanges NANPA lists for Eureka are in 636.
How many phone companies have exchanges in Eureka?
4, holding 6 exchanges between them, according to NANPA's 10/01/2026 file.
Can I keep my existing Eureka business number?
Yes. Porting an existing number to Callata is free. Texting from it starts after carrier registration (10DLC), a one-time $49 fee.
How much is a business phone line in Eureka?
Callata is $99 a month with 5 users included, then $20 per additional user, with up to 3 local numbers; 18 users come to $359.00 a month. For comparison, 18 users on RingCentral RingEX Core list at $540.00 a month (checked September 28, 2026).