A business phone system that answers when your team can’t

We’ve run business phone lines since 2016: numbers in 14 countries, menus, queues and desk phones, all from one account. Now that business phone system has an AI receptionist on the line too. It takes the calls nobody’s free for, books what it can and passes the rest to the right extension.

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  • Phone lines since 2016
  • Local numbers in 14 countries
  • Calls between extensions cost nothing

Every busy office knows the 8:30 rush

Three lines light up at once. The receptionist is checking someone in, the practice manager is talking to a supplier, and a fourth caller gets the engaged tone and rings the practice down the road.

Nobody did anything wrong. There just weren’t enough hands.

“Is there any chance of something before work tomorrow?”A patient, 8:31 on a Monday

Making sure a call reaches someone has been our job for years: better routing, a queue, a ring group, a mobile on divert. Now the line can also answer for itself, and it knows when to hand back to a person.

Follow a call

Where a call goes when your number rings

Five steps, and your own team gets the first chance at every call. Each one has its own page if you want the detail.

  1. Your line rings

    Someone dials one of your numbers: a local one in Leeds or Dublin, say, or a mobile or toll-free line. There are numbers in 14 countries to choose from.

  2. Your team gets first go

    The call follows the route on your call flow map: a greeting, perhaps a short menu, then a queue or a ring group, so a colleague can pick up first.

  3. If nobody’s free, the agent answers

    You set how many seconds your team gets. After that the AI agent picks up, checks the diary and the apps you’ve allowed, and books what it can. If you’ve connected WhatsApp, it can also send an approved confirmation message before the caller rings off.

  4. A person when it matters

    “Could I speak to someone in accounts?” The agent transfers the caller straight to the accounts extension, and a ring group or a colleague’s mobile works the same way. If nobody answers, your route decides what happens next.

  5. Everything’s written down

    Every call lands in the call history with its length and cost. Calls the agent took also keep a transcript, a recording and a list of what it did.

What used to end at the engaged tone now ends with a booking or the right colleague on the line, and there’s a written record either way.

Three offices, and how their lines are set up

The businesses are made up. The set-ups are ordinary, which is rather the point.

A physio clinic with two sites

Both receptions, in Nottingham and Derby, open at 8:30, and so do the phones. On a Monday the second and third callers got the engaged tone, and most rang back at lunch, if at all.

Each site’s number rings its own reception ring group. Anything still ringing after 20 seconds is answered by the AI agent, which can see both sites’ diaries in Casatel Calendar. A patient who can’t get a Derby slot before Friday is offered Wednesday at 7:45 in Nottingham and takes it. Someone asking about her knee after surgery doesn’t get advice from the agent; she’s put through to the duty physio’s extension.

Reception looks after whoever’s at the desk, and the diary’s right before nine.

A recruiter with offices in Birmingham and Dublin

Candidates in Ireland didn’t like ringing a UK number, and the two offices ran up a bill just talking to each other.

Irish candidates ring a Dublin number and hear a two-option menu: 1 for the Dublin consultants’ ring group, 2 for the AI agent, which books interview slots. Birmingham’s client line goes into a queue with music. Consultants ring each other on three-digit extensions for nothing, and Friday’s catch-up happens in a conference room with a PIN.

Two offices in two countries work as one team, on one account and one balance.

An electrical contractor in Leeds, closed for Christmas

Shutting for a fortnight meant a voicemail box nobody wanted to open on 2 January, and the odd emergency went unanswered.

On Christmas Eve the office manager opens the call flow designer and drags the main number onto a closure announcement, then the AI agent. It takes quote requests and books visits for the first week back. Her instructions say a house with no power at all is urgent, so a customer who rings at 9 pm on the 27th is put through to the on-call hunt group, which tries both electricians’ softphones in turn. In January she drags the number back.

The office gets a proper break, and the first week back already has visits in the diary.

More set-ups, trade by trade

Phone system

The phone side, which came first

This is where we started, and it still carries every call you get. The agent only picks up what your team can’t reach in time, and all of this comes with the account.

Numbers in the UK, Ireland and 12 more countries

Local, mobile or toll-free, depending on the country, and the price is on screen before you buy.

Cloud PBX

Your office switchboard as a cloud phone system: we host it, and you manage it from any browser.

Keypad menus (IVR)

Up to 12 options on the keypad, * and # included, and a sensible route for callers who press nothing.

Queues for the busy hour

Callers wait in turn with music, and calls are shared by one of five strategies.

Hunt groups and ring groups

Try each phone in the order you set, or ring them all at once.

Desk handsets and softphones

Every phone gets a three-digit extension, and the first five on the account are free.

Meeting lines with a PIN

A conference room that’s always there, free to join from any extension.

Closure and holiday notices

“We’re closed today, back at eight”, played before anyone picks up.

Audio store for prompts and hold music

Record in the browser or upload a studio file, and it’s converted to phone quality.

Calling abroad, and calling each other

Ring 180+ countries from the same desk phone. Calls between your own extensions cost nothing.

2016running business phone lines
14countries with local, mobile or toll-free numbers
5SIP phones included free
12keypad options per IVR menu
The AI agent

Instructions in plain English, written by you

You tell it who it is, what it may do and when to put a caller through to a person. Pick one of seven English voices, start from one of 25 agent templates or 15 complete call flows, then change whatever you like.

  • Answers from what you’ve written down and what its tools return, nothing else
  • Books, moves and cancels in Casatel Calendar or Google Calendar
  • Looks things up in the apps you connect
  • Puts callers through by the names they use: “accounts”, “the yard”, “Gareth”
  • Emails you the transcript after every call, if you want it

How the AI phone agent works The 15 call flow templates

Apps the agent can check during a call

GCGoogle CalendarGSGoogle SheetsHSHubSpot CRMATAirtableSBSupabaseNCNocoDBDBMySQLWPWordPress

Three more things in the account

You don’t need any of these to get started. They’re there for when the phone line isn’t the whole story.

Phone CRM

For firms without a CRM, or with a spreadsheet doing the job of one. Customer files sit beside your call history: start from a template (there are six) or import the spreadsheet. When someone rings, the agent finds their file by the number they’re calling from and can correct an out-of-date mobile there and then. If you’re already on HubSpot, stay on HubSpot.

A shared WhatsApp inbox

The front desk answers WhatsApp messages from one place, and can send an approved notice to a list when there’s news. Anyone who replies STOP comes off your campaigns.

Callbacks only after a YES

If you’d like the AI agent to ring people back, your business asks each of them on WhatsApp first. Calls go out within local calling hours, never to a number on your do-not-call list, and every answer is kept on file.

An answering app, a business phone system, or both on one line

If you already pay for an AI answering service and a separate phone line, you may have found the two don’t talk to each other. Here’s how the three set-ups compare.

What you needAI answering appTraditional phone systemCasaTelecom
An AI voice that answersYes, it’s the whole productNot usually, or as an extraYes, from 25 agent templates
Business numbers of your ownSometimes, in a handful of countriesYes14 countries: local, mobile or toll-free
Putting callers through to staffOften just to one mobileYes, it’s what it’s forAny extension, ring group or mobile, by the name the caller asks for
Menus, queues and ring groupsSeldomYesYes, all drawn on one call flow map
A diary the agent can bookUsually a separate toolNoCasatel Calendar built in, or Google Calendar
Transcripts and recordingsYes, for its own callsCall recordings onlyBoth for every AI call, with each action the agent took
Logins and billsTwo or more, once you add phonesTwo or more, once you add AIOne login and one prepaid balance
FAQ

Questions we hear most

Not covered here? Send us your question

How much can the agent sort out without us?

Quite a lot, inside the limits you set. It answers from its instructions, books into the diary, looks things up in the apps you connect and puts callers through to people. It only knows what you’ve written and what its tools return, so anything beyond that belongs with a colleague, and your instructions can say exactly when to put the call through.

Which diary does it book into?

Casatel Calendar, which comes built in, or your own Google Calendar. It won’t offer a time that breaks your booking rules (opening hours, appointment length, gaps, minimum notice, how far ahead), and callers never hear what else is in the diary. It can book, move and cancel. How AI appointment booking works.

How does a caller get past the agent to one of us?

By asking. “Can I talk to Siobhan?” reaches Siobhan’s extension, because you’ve told the agent which phones, ring groups and queues it may use and what people call each one, “the workshop” included. If nobody picks up, the call goes wherever your route sends unanswered calls. More on smart call transfer.

Which of our own systems can the agent look at during a call?

HubSpot, Airtable, Google Sheets and Google Calendar, Supabase, MySQL, NocoDB and WordPress. You add each one as a tool and tick what the agent may do with it: read, add, change or remove. Anything you haven’t ticked, it can’t touch. What each app can do on a call.

We have SIP desk phones already. Can we keep them?

Yes. Each handset gets a three-digit extension on your account. Anyone who’d rather not have one on the desk can use a softphone app on a laptop or mobile instead, and the first five SIP phones on the account cost nothing. Desk phones and softphones.

Could we have an Irish or Spanish number alongside the UK one?

Yes. Alongside the UK and Ireland there are numbers in Spain, Portugal, France, Italy, Germany and the Netherlands, plus Australia, Brazil, Canada, Mexico, Puerto Rico and the United States. Which types you can have (local, mobile or toll-free) varies by country, and the price shows before you pay. Browse virtual phone numbers.

Which languages does the agent speak?

Just English, in a choice of seven voices. Recordings are another matter. A Welsh greeting or Polish hold messages are fine, because you record or upload them yourself and keep them in the audio store.

Is there a monthly fee, or do we pay as we go?

You pay as you go. Opening an account is free. Numbers, extra phones, calls and extra calendars come off a prepaid balance, and every price is shown before you buy. Numbers renew from the balance and extra phones are charged every 30 days. If you’d like figures for a particular set-up, send us the details and we’ll work them out.

Are our call recordings and customer details kept private?

They stay in your account, and only people who log in to it can open them. Passwords and keys for your connected apps are stored encrypted, and each action the agent takes in those apps is logged. In the phone CRM you choose which fields to encrypt, with a key that belongs to your account alone.

We only want the phones sorted. Is the rest optional?

Yes. A single number, an AI agent and a handful of SIP phones is a perfectly good place to start, and to stay. The built-in phone CRM and the shared WhatsApp inbox are in the account if they turn out to be useful later.

Does the agent ever ring people itself?

Not on its own initiative. Outbound AI calls run as campaigns, and a number is only rung once that person has answered YES to a question your business sent on WhatsApp. Each call is checked against your do-not-call list just before it goes out, and it has to fall within local calling hours. It’s only available on a main account, once your business is verified. Ask for consent before AI calls.

One number and one agent is enough to begin

Open a free account, buy one number and point it at a ring group with the agent behind it. The app’s setup guide covers the rest in seven steps, and if you’d rather talk it over first, we’re on the phone.

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