CallataGuidesBusiness phone system for architectural services firms in St. Louis, MO-IL
Architectural services firms in the St. Louis, MO-IL metro area: 170 establishments in 2023, the local area codes, and what phone service costs a 12-person team.
- Establishments
- 170CBP 2023
- Employees
- 2,020mid-March 2023
- Per 100k residents
- 6.0U.S. 6.7
- Rank
- 24th of 431areas by count
The architecture firm market in St. Louis, MO-IL
County Business Patterns counts 170 architectural services firms (NAICS 541310, Architectural Services) in the St. Louis, MO-IL metro area for 2023. Together they reported 2,020 mid-March employees and $216.1 million of payroll for the year. That ranks 24th of the 431 metro and micropolitan areas where Census published a count for this industry.
With 2.8 million residents in the Census 2024 estimate, that is 6.0 architectural services firms per 100,000 people, 9.8% below the national rate of 6.7. Establishments average 11.9 employees, 43.0% above the U.S. average of 8.3. Payroll per employee comes to $106,963, 8.4% above the national $98,717.
| Measure | St. Louis, MO-IL | Missouri | United States |
|---|---|---|---|
| Establishments | 170 | 333 | 22,805 |
| Mid-March employees | 2,020 | 4,390 | 189,468 |
| Annual payroll | $216,065,000 | $444,867,000 | $18,703,680,000 |
| Employees per establishment | 11.9 | 13.2 | 8.3 |
| Payroll per employee | $106,963 | $101,336 | $98,717 |
| Establishments per 100,000 residents | 6.0 | 5.3 | 6.7 |
Census County Business Patterns 2023 (mid-March employment; annual payroll). Employees and payroll flagged high-noise are shown but not used in the text. Residents: Census Vintage 2024 estimates.
Establishment size: architectural services firms in St. Louis, MO-IL
Of the architectural services firms in St. Louis, MO-IL that had employees in March 2023, 54.4% had fewer than five (the U.S. share is 63.6%). 73.4% had fewer than ten. Small teams usually share the phone: the person who answers is often also serving a customer or doing the job, which is when calls get missed.
| Employment size | Establishments | Share | U.S. share |
|---|---|---|---|
| 1–4 employees | 92 | 54.4% | 63.6% |
| 5–9 employees | 32 | 18.9% | 17.6% |
| 10–19 employees | 21 | 12.4% | 10.2% |
| 20–49 employees | 19 | 11.2% | 5.9% |
| 50 or more employees | 5 | 3.0% | 2.7% |
Employment-size classes count establishments by mid-March 2023 employment. Establishments with no March employees are excluded from the size classes, so shares are of establishments with employees. Source: Census County Business Patterns 2023.
Why the phone matters for architectural services firms in St. Louis, MO-IL
Architects coordinate clients, consultants, contractors and permitting offices across long projects. Calls need to reach the project lead, and summaries of decisions help keep teams aligned. That holds for architectural services firms in St. Louis, MO-IL as much as anywhere.
A few of the calls that come in to architectural services firms in St. Louis, MO-IL:
- The firm calls a client to review a design.
- A contractor calls with a question about drawings.
- A permitting office calls about a submission.
When nobody can pick up
After-hours calls are usually not urgent.
Callata transcribes voicemail and triages it for urgency, so the first callback in the morning can go to the caller who needs it most.
Phone system pricing for a 12-person architecture firm
The average architecture firm in St. Louis, MO-IL has 11.9 employees, so a 12-person team is a reasonable benchmark. Priced per seat, 12 users would run $360.00 a month on RingCentral RingEX Core and $299.40 on Ooma Office Pro (month-to-month list prices, checked September 28, 2026). On Callata the same 12 people cost $239.00 a month, less than either per-seat plan.
The annual difference against RingCentral's monthly list price comes to $1,452. Some vendors discount annual contracts; the table shows month-to-month prices.
| Provider (plan) | Pricing basis | Per month | Per year |
|---|---|---|---|
| Callata (Callata Office) | $99 incl. 5 users, $20 per extra user | $239.00 | $2,868.00 |
| Quo (Starter) | $19.00 per user | $228.00 | $2,736.00 |
| Nextiva (Core) | $23.00 per user | $276.00 | $3,312.00 |
| Ooma (Office Pro) | $24.95 per user | $299.40 | $3,592.80 |
| Dialpad (Standard) | $27.00 per user | $324.00 | $3,888.00 |
| RingCentral (RingEX Core) | $30.00 per user | $360.00 | $4,320.00 |
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.
Local area codes for architectural services firms in St. Louis, MO-IL
NANPA records place the exchanges of the area's named cities and towns in 8 area codes. 314 has the most, with 723 of 1,483 exchanges (49%). Callata's plan includes up to 3 local numbers; you can pick them in the area codes your clients recognize, subject to carrier inventory, or port the number you already have for free.
| Area code | Exchanges | Time zone | In service since | Overlay with |
|---|---|---|---|---|
| 314 | 723 | Central | 1947 | 557 |
| 618 | 324 | Central | 1947 | 730 |
| 636 | 308 | Central | 1999 | none |
| 557 | 71 | Central | 2022 | 314 |
| 730 | 30 | Central | 2023 | 618 |
| 217 | 14 | Central | 1947 | 447 |
| 573 | 11 | Central | 1996 | 235 |
| 447 | 2 | Central | 2021 | 217 |
Exchanges are NANPA-assigned central office codes (NPA-NXX) in the rate centers matched to the area's named places. Source: NANPA utilized code and NPA reports.
Setting up Callata for an architecture firm in St. Louis, MO-IL
For $99 a month, Callata puts a team of up to 5 on one plan ($20 for each person after that): up to 3 local numbers, unlimited inbound calls, a pooled allowance of 1,500 outbound US and Canada minutes per user, browser and cell calling, voicemail transcription with urgency triage, recorded calls with AI summaries and business-hours routing, with E911 on every number.
If you already have a number in St. Louis, MO-IL, porting it to Callata is free. Texting from a local number requires a one-time carrier registration (10DLC, $49), and the numbers available in any area code depend on carrier inventory when you choose them.
Optional AI agents (receptionist, sales, support or scheduler) can answer calls after hours or when nobody picks up, take messages, text, email and transfer to your team. They are billed from prepaid AI minutes at $0.25 per minute, identify themselves as AI, and may only place outbound calls to people who consented, between 8am and 9pm.
Frequently asked questions
How many architectural services firms are there in St. Louis, MO-IL?
Census County Business Patterns counted 170 architectural services firms in the St. Louis, MO-IL metro area in 2023. They employed 2,020 people in mid-March.
What does a business phone system cost for a 12-person architecture firm?
At month-to-month list prices checked September 28, 2026, 12 users cost $360.00 a month on RingCentral RingEX Core and $299.40 on Ooma Office Pro. On Callata, $99 a month with 5 users included, then $20 per additional user, the same team pays $239.00.
What area code should an architecture firm in St. Louis, MO-IL use?
Area code 314 has the most assigned exchanges among the area's named places, followed by 618 and 636. If you already have a local number, you can port it to Callata for free.
Can an AI receptionist answer calls for an architecture firm?
Yes. Callata's optional AI agents can answer when the team is busy or closed, take a message, text, email or transfer the call. They disclose that they are AI and are billed from prepaid AI minutes at $0.25 per minute.