Your phone system should know who is calling.
Every call to a venue is a lead with a name, a date and a budget. Most phone systems greet it with ten digits and a shrug. Here are three ways to run your phones, what we use ourselves, and what plugs into Seat Four.
Three ways to run your phones
Choose the one that fits the size of your front desk. None of them is wrong, and they stack: a PBX can sit on a Twilio trunk, and Twilio can sit under GoHighLevel.
GoHighLevel phone (LC Phone)
HighLevel's own phone service, switched on inside the CRM. Calls and texts land on the contact's timeline, and the numbers live in your GoHighLevel account.
Pros
- Easiest to set up: it is already inside the CRM
- Calls and texts sit on the contact timeline
- No phone system to run, patch or back up
- Voice AI is built in
Cons
- Costs more per minute than raw Twilio, because of that extra per-minute fee
- Not a PBX: no extensions or desk-phone model
- Tied to GoHighLevel. Moving numbers out goes through HighLevel Support, and recordings, voicemails and contacts do not move with them
Who it fits
Venues already on GoHighLevel, with one or two people answering and nobody to run a server.
US and Canada rates from HighLevel's help pages, October 2026.
Your own Twilio account We recommend this
Twilio is the carrier. You open an account, buy numbers in your own name and pay per minute. Everything else on this page can sit on top of it, GoHighLevel and PBXs included.
Pros
- The numbers are in your name, so you can change software without losing them
- Lower per-minute prices than LC Phone at today's rates
- A full API and webhooks, so AI agents and software like Seat Four can plug in
- Works under GoHighLevel and under a PBX
Cons
- Not a phone system on its own: you pair it with a PBX, GoHighLevel or code
- One more account and one more bill
- Texting needs carrier registration (A2P 10DLC) on top
Who it fits
Anyone who wants to own their numbers, and anyone planning an AI voice agent. Seat Four's phase-two plan runs on your own Twilio account. That part is planned, not built.
Twilio list prices, US, October 2026. Outgoing SIP rates vary by destination.
A real PBX
A PBX is the phone system proper: extensions, ring groups, voicemail, desk phones and a mobile app. It reaches the outside world through a SIP trunk, such as a Twilio one.
Pros
- Real extensions, ring groups and voicemail
- Desk phones that just ring
- A mobile app for staff, on 3CX and FreePBX
- APIs that software like ours can use
Cons
- Something to run, update and back up
- 3CX is closed source with an annual fee, and its API features sit in the top edition
- Mobile apps vary: we could not confirm an official FusionPBX app
Who it fits
Venues with a front desk, several people answering, or desk phones that have to keep ringing. Two to twenty people on the phones is the sweet spot.
3CX prices are list, per year, before tax, October 2026.
What the minutes cost
Carrier rates only: no PBX licence, no number rental. Drag the slider.
LC Phone costs more per minute because the CRM is part of what you buy. Outgoing SIP rates start at 0.11¢ and vary by destination, so that bar is a floor, not a quote. Full per-minute breakdown, with AI voices, on the costs page.
What we use, honestly.
The people building Seat Four run 3CX at their own venue today, and have for years. They like it for the unglamorous reasons that matter on a busy Saturday: it is stable, it is easy to use, it has the features, the interface makes sense and the mobile app works.
Before 3CX, we ran Asterisk.
We love open source. We plan to move to an open-source PBX, and to bring the integrations below to a free PBX. There is no date, and nothing for a free PBX is built today.
Seat Four is not affiliated with 3CX. We tell you what we run so you can weigh everything else we say about phones.
- BeforeAsterisk
- Today3CX
- Next, plannedAn open-source PBX
Pick up already knowing who it is
Caller lookup is live in our own setup today. The rest is at different stages, and the chips say which. Press play, or click any step.
- Tour booked, Saturday 11 AM
- Proposal sent
- Inbound call, 4:12 Recording, transcript and summaryPlanned
The phone rings. All 3CX has is a number.
- Live in our setupCaller lookup on every incoming call
3CX asks the CRM who is calling, through n8n. The caller's name and record show in the 3CX web client.
- Built, in testingClick-to-call from Seat Four
Uses the 3CX Call Control API (makecall). Tested against a mock so far, with dry run on by default.
- PlannedCall logs, recordings, transcripts and summaries on the lead
Written back to the lead when the call ends, using 3CX call journaling (ReportCall).
- PlannedNew-lead alerts to the team
The team hears about a new lead the moment it arrives.
- Planned, unconfirmedCaller popup in the mobile app
We have not confirmed that the 3CX mobile app shows the CRM match, so we only claim the web client.
Pick where your phone should ring, then press call. Seat Four asks 3CX to place the call from that device.
Pretend call. Nothing is dialled on this page.
The real adapter ships with dry run on, a contact allowlist, and a refusal to dial emergency or premium numbers. It also refuses 555-01xx numbers, so our demo caller is safe.
The fine print. 3CX asks, on every call. Nothing pushes leads into 3CX. Today the lookup is answered by our own n8n workflow; Seat Four's own caller lookup is planned. 3CX's documentation puts CRM lookup in the Pro and AI editions and the Call Control API in the AI edition with 8 or more simultaneous calls. Which screens show the name (desk phones, mobile app) we have not measured. Everything on this stage uses fictional data.
A short history of the open-source phone
Asterisk is the engine under much of the open-source phone world. Here is who has owned it, and what is going on now. Click any year.
Mark Spencer creates Asterisk at Digium
It becomes the engine under many open-source phone systems, FreePBX among them. The licence is GPLv2. Source
Sangoma acquires FreePBX
FreePBX is the web interface a lot of Asterisk users know. Its core is GPLv3, and some add-on modules are sold under their own licences. Source
Sangoma acquires Digium, Asterisk's creator
The price was about US$28 million. Sangoma's merger FAQ said both projects stay under the GPL and that the code cannot be taken back out of it. Source
FreePBX 17 reaches general availability
It runs on Debian and supports Asterisk 22. The FreePBX framework repository was still being updated in late September 2026. Source
Asterisk 22.11 (LTS) and 23.5 ship
Development is busy: the Asterisk repository took new commits this week, 272 of them over the last year, as of October 14, 2026. Releases
Sangoma agrees to be acquired by BRC Group Holdings
BRC calls itself a diversified holding company with operations in financial services, communications and retail. Enterprise value is about US$204 million. The deal is pending: it needs a Sangoma shareholder vote, court and exchange approvals and US antitrust clearance, and is expected to close no later than early 2027. The announcement does not say what happens to Asterisk or FreePBX. Press release
Asterisk 24, the next LTS line
On the Asterisk project's schedule, version 24 is the next long-term support release. Release candidate 2 is out. We have not seen the final release. Schedule
Asterisk is not dead. It changed owners, and some people worry about where it goes next.
What we know
- Asterisk is GPL. The code already published stays published, and anyone may fork it.
- Releases are on schedule: 22 is the current LTS, and 24 is next.
- Sangoma is publicly listed, and so is the buyer. This is not a private equity buyout.
- We found no licence change.
What nobody knows yet
- What BRC plans for Asterisk and FreePBX after closing. The announcement is silent on it.
- Whether contributors sign an agreement that lets the owner relicense. We could not confirm either way.
- Whether the worry is justified. FreePBX sells paid add-ons and a financial holding company is buying the main steward. That is a reason to watch, not evidence of anything.
Best PBX options in 2026
Three of these are not phone systems at all, and we say so. Filter the list, or read the lot.
| Option | Licence | Hosting | Mobile app | CRM and API hooks | Best for |
|---|---|---|---|---|---|
| 3CXCommercial | Closed source. Free Basic: 4 calls, 10 users. Paid from $300 a year (8 calls), up to $1,095 (16 calls, AI) | Self-hosted or on-prem. 3CX hosting costs extra | iOS and Android, plus web client and Windows softphone | CRM template in Pro and AI. Call Control and Configuration APIs need 8 calls or more on AI. None on Basic | A polished PBX with apps and one flat yearly price |
| FreePBX 17Open source | GPLv3 core, plus paid commercial modules | Self-hosted (Debian), or Sangoma cloud | Sangoma Connect app. Parts need paid licences | Commercial CRM modules. Asterisk ARI and AMI underneath | Asterisk with a web interface and the biggest install base. Owner change pending |
| FusionPBX on FreeSWITCHOpen source | MPL (FusionPBX, FreeSWITCH) | Self-hosted | No official app we could confirm | Event socket, XML-CURL, REST | Multi-tenant setups and tinkerers who want to program it |
| Wazo PlatformOpen source | GPL-3.0 | Self-hosted, container, or Wazo.io hosted | WebRTC and a React Native demo app. A branded Wazo app we could not confirm | REST APIs and webhooks for every service, JavaScript SDK | Custom integration. It is API-first |
| VitalPBXFreemium | Free Community tier capped at 12 extensions. Paid from $100 a month. Source licence unconfirmed | Self-hosted | Two mobile clients, on paid plans | CRM Connector add-on, API and AMI | Small teams under 12 extensions |
| KamailioNot a PBX | GPL | Self-hosted | None | A SIP proxy: routing, load balancing, registrar. No voicemail, IVR or extensions | Sitting in front of other phone systems |
| TwilioNot a PBX | Commercial cloud service, pay per use | Twilio cloud | SDKs for iOS, Android and browser, to build your own | Full REST, webhooks and Media Streams | The carrier layer under everything else, and AI agents |
| GoHighLevel LC PhoneNot a PBX | Commercial cloud service, pay per use | HighLevel cloud | HighLevel mobile app and web | Native to the GoHighLevel CRM, calls on the contact timeline | Venues already on GoHighLevel who want nothing to run |
A voice agent is just another extension
Seat Four does not run an AI phone agent itself yet. There are two ways to plug one into your phones, and a cheap way to turn calls into text.
As a PBX extension
3CX Programmable Extensions let an outside app register like an extension. It takes calls, streams audio both ways over the Call Control API, and can transfer, send to voicemail or hang up.
3CX documents it for V20 Update 10 and an AI-edition licence, with examples for OpenAI, Gemini, Grok and Qwen.
Over Twilio Media Streams
A line of TwiML opens a two-way WebSocket from the call to your agent. Twilio sends the caller's audio in 8 kHz mu-law frames and plays whatever audio you send back.
One two-way stream per call. Your server must be reachable by Twilio.
After the call
Turn the recording into text. 3CX call journaling can carry a transcript and summary itself, so you may not need a separate step.
We have not seen published accuracy figures for phone-quality audio.
ElevenLabs Scribe v2
$0.22 per hour of audio, list price
- Speaker labels (diarization)
- Word-level timestamps
- 90+ languages
- A 4-minute call is about 1.5¢
- 0:02CallerHi, is Saturday at eleven still open for a tour?
- 0:06VenueIt is. Mark, right? I can see your proposal went out Thursday.
- 0:11CallerThat is me. Can we bring my parents?
- 0:14VenueThe more the merrier. Parking is on the left.
Made-up call, shown only to illustrate speaker labels and timestamps.
The honest answers
Do I need a PBX to use Seat Four?
No. A PBX is for the people answering your phones, not a requirement of Seat Four. GoHighLevel's phone or your own Twilio number work without one. A PBX earns its place when several people answer calls, you want desk phones, or you want ring groups. Anything marked planned on this page is not built yet.
Is Asterisk dead?
No. Asterisk is actively developed: version 22 is the current long-term support line and version 24 is scheduled for October 15, 2026. It has changed owners, though. Sangoma, which owns Asterisk and FreePBX, agreed in September 2026 to be acquired by BRC Group Holdings, a public holding company. The deal is pending. We found no licence change, and nobody has said publicly what happens to Asterisk after the sale.
Is 3CX free?
3CX has an official Free Basic edition: 4 simultaneous calls and up to 10 users, self-hosted, with no CRM integration or API. 3CX's own page for it is live as of October 14, 2026, although some blog posts claim a free tier ended in January. The caller lookup we run needs a paid edition: 3CX's documentation puts CRM integration in Pro and AI, and its Call Control API in the AI edition with 8 or more simultaneous calls.
Can I use my own Twilio numbers with a PBX?
Yes. Twilio Elastic SIP Trunking exists for this: you point your PBX, such as 3CX or FreePBX, at a trunk, and the numbers stay in your Twilio account. A SIP trunk costs 0.34 cents a minute for incoming calls on a local number, 1.3 cents on toll-free, and outgoing starts at 0.11 cents and varies by destination.
Will Seat Four work with a free PBX?
That is the plan. We run 3CX today and intend to move to an open-source PBX, and to bring the same integrations to a free one. There is no date, and nothing for a free PBX is built yet.
Why settle for a phone that only knows it is ringing?
Join the beta list and we will tell you as each phone integration moves from planned to live. Seat Four is named after a number bigger than three, on purpose.
3CX, Sangoma, FreePBX, Asterisk, Twilio and GoHighLevel (LC Phone) are trademarks of their owners. Seat Four is not affiliated with, endorsed by or sponsored by any of them. Their names appear to describe compatibility and to compare options. Prices and facts come from public vendor pages checked on October 14, 2026, and they change, so check the vendor before you buy.
Sources, checked October 14, 2026
- 3CX CRM integration, Call Control API and Programmable Extensions
- 3CX Free Basic edition
- Asterisk versions and schedule and releases
- BRC Group and Sangoma announcement
- Sangoma and Digium FAQ
- Twilio Voice and SIP trunking pricing
- HighLevel LC Phone pricing
- ElevenLabs API pricing
- Wazo Platform and VitalPBX plans