How to set up an AI receptionist: step-by-step UK guide

An AI receptionist can do anything your receptionist does on the phone, once it knows what your receptionist knows and can use the systems your receptionist uses. The technology is ready: it answers at once, understands accents and tone, and speaks naturally. What decides how much it does for you is an afternoon of preparation by the person who knows the business best. That is you.

This chapter of our AI receptionist guide walks through the set-up in nine steps. The steps apply to any provider. Where it helps, we show the matching screen in Line, the phone system we make, so you can see what each step looks like in practice.

What you need before you start

Gather these first. Each one saves a round of fixes later.

• Your prices, or the price ranges you are happy to give on the phone.
• The five calls you get most. Look at your last 30 calls or messages, or ask whoever answers the phone.
• Who deals with what: the person who calls back new enquiries, who handles complaints, and who is on call for emergencies.
• Your opening hours, including bank holidays and planned closures.
• Access to your phone line or mobile settings, to switch on forwarding.
• Access to your website, to update the privacy notice.

Step 1: Decide which calls the AI answers

Choose one of three set-ups. You can change later, so start with the one you trust.

You do not need a new number. Callers keep dialling the number they know, and your line forwards to the AI receptionist. You can also take a new number for a new line or a marketing campaign.

Forwarding codes for UK phones

Dial these from the phone that owns your business number, replacing the number with the AI receptionist's number. Most UK mobile networks and BT, Sky, Virgin Media and TalkTalk landlines use them. Some phones need two stars at the start instead of one.

Network charges can apply to forwarded calls. Our guide to forwarding calls to another phone has the details for iPhone, Android and each landline provider.

A mobile cannot forward by time of day. To send calls to the AI only after hours, you need a business phone system with opening hours, which you set in step 7.

Step 2: Write your business facts

This sheet is the AI receptionist's whole knowledge of your business. It answers from these facts and, if you set it up properly, from nothing else. Every gap is a question it cannot answer.

Write it as plain facts, not marketing copy. "Boiler service: £85, takes about an hour, we cover CF and NP postcodes" works. "We offer a comprehensive range of heating solutions" does not.

The template library above includes the facts sheet, the systems access plan, the call rules, the handover rules, the message fields and the tone guide used in the next steps. Fill in the facts sheet first.

In Line: when you sign up, Line reads your website and drafts the facts for you. Check every line: websites are often out of date on prices and areas. You then keep them as knowledge documents, and choose which ones each receptionist uses in its Conversation section.

Prices: give them, or don't

Decide what the AI may say about money. There are three safe positions:

1. Fixed prices for fixed jobs: "A boiler service is £85."
2. From prices with a reason: "Rewiring starts at about £3,000 for a two-bed flat. We quote after a visit."
3. No prices, with a reason: "Every job is different, so we quote after a short chat. Can I take your details?"

The unsafe position is silence: no prices in the facts and no rule. That is when an AI is most tempted to guess.

Step 3: Connect the systems your receptionist uses

Facts answer questions. Systems let the receptionist act. Make a list of what your receptionist, or you, open during a normal day of calls: the diary, the customer list, the jobs board, the order system, the accounts. Each one you connect is a kind of call the AI can deal with instead of writing down.

There are three ways in:

1. Built-in connections. Calendars connect in a few clicks with your Google or Microsoft account.
2. MCP. Many business tools now publish an MCP server, an open standard that offers their actions to AI agents. Add the server's address and the receptionist can use its tools: find a customer, check a job, create a booking.
3. An API. For a system without an MCP server, add an HTTPS endpoint with a short description of what it does and what it needs. "Get job status by postcode" is a typical first one.

For each action, set the receptionist's authority, the way you would for a new starter:

Put hard limits, such as a maximum credit, in the system's own rules, not only in the instructions. Keep passwords and keys in the provider's secret store, never in the instructions.

In Line: the receptionist's Tools section holds its calendars, MCP servers, API tools and your published workflows, each with its own setting. Keys are saved encrypted, by name, and are never shown to the AI.

Step 4: Write the instructions

The instructions tell the AI receptionist who it is, what it is for, and what to do with each kind of call. Providers call them different things: a prompt, a script, a persona, instructions. They all work the same way.

Start with three lines:

• Name and role: "You are Sam, the virtual receptionist for Hartley Plumbing."
• Objective: "Answer every call, settle simple questions from the facts, and take full details for anything else so the team can call back."
• Voice: pick one that suits your callers, and keep the same one.

Then write a rule for each of your five most common calls, using the call handling rules template. Each rule says what to ask, in what order, and what to promise.

Good and bad instructions

Short, specific rules beat long, general ones. These are the mistakes we see most:

A complete example

Here is a full instruction set for a made-up two-person plumbing business. Use it as a model for your own.

ROLE
You are Sam, the virtual receptionist for Hartley Plumbing, a two-person
plumbing and heating business in Cardiff. You answer calls when Dan and
Rhys are on jobs or the office is closed.

OBJECTIVE
Answer every caller, deal with their request on the call where you can,
and leave Dan only the decisions that need him.

RULES
- Say you are a virtual assistant in the greeting.
- Answer from the FACTS below and your tools. If neither has the
  answer, say: "I'll check that with Dan and get him to call you."
- One question at a time. British English.
- Read every phone number and postcode back to the caller.
- Never promise a date or a price that is not in the FACTS.

CALLS
New job: ask name, number, postcode, what the problem is, and when
suits for a call back. Say Dan calls back today before 6pm.
Existing job: find the job with check_job by name and postcode. Tell
them the date and engineer. To move it, offer free slots from the
calendar and book the new one.
Boiler service booking: offer the next two free Tuesday or Thursday
mornings from the calendar and book the one they choose.
Emergency (gas smell, water pouring, no heating with a baby or elderly
person in the house): gas smell means tell them to leave the building and
call 0800 111 999 now. For the others, mark the message URGENT and say
Dan will call within 30 minutes.
Complaint: listen, say sorry once, and check the job. You may rebook a
return visit free of charge. Anything else, such as money back, goes
to Dan marked URGENT: tell the caller he will call by 6pm.
Sales call: say we're not interested, thank them, end the call.

FACTS
Areas: CF postcodes and NP10, NP18, NP19. No work outside these.
Hours: Mon–Fri 8:00–17:30. Sat 9:00–12:00 emergencies only.
Boiler service: £85, about an hour. Call-out: £60 first hour.
Payment: card or bank transfer on completion.
Gas Safe registered. Guarantee: 12 months on parts and labour.

TOOLS
calendar: find free slots, book and move visits (Run).
check_job: job date, engineer and status by name and postcode (Run).
add_job_note: add a note to a job (Run).

Step 5: Set the handover rules

Handover rules decide the moments you want a person, how quickly, and what the caller is told. They are not a list of things the AI cannot handle. An AI receptionist hears an upset caller, follows your complaints policy and puts things right within the authority you gave it in step 3. Handover is for the decisions you keep.

Most businesses set four:

1. The caller asks for a person.
2. The remedy is beyond its authority, such as money back above your limit.
3. The decision is one you keep, such as credit terms, or regulated legal, medical or financial advice.
4. Someone is at risk. Tell the caller to ring 999 or the relevant emergency line first, then tell the person on call at once.

For each, set who is told and how: a text, an email, a notification in your app. Then set what the caller hears: "I've marked this urgent for Dan. He'll call you within 30 minutes." Only promise a time your team can keep.

In Line: handover rules sit in the receptionist's Procedures section, next to the step-by-step procedures for set requests. Each rule names when it applies and who takes over.

Step 6: Write the greeting

The greeting is the first thing every caller hears. Keep it under ten seconds. It needs three things: your business name, that the caller is speaking to a virtual assistant, and one open question.

Hello, you're through to Hartley Plumbing. I'm Sam, the virtual assistant. How can I help today?

Say it is an assistant. UK law has no general rule that you must, but the CMA expects businesses not to mislead customers about AI, and the EU requires it for callers in the EU from 2 August 2026. Callers also take it better than you might expect: in a January 2026 survey of 5,001 UK adults, 68% were comfortable with an AI that could hand them to a person (Moneypenny / Censuswide, a vendor study). Our chapter on AI receptionists and UK law has the details and the privacy notice wording.

The greeting generator writes a matching opening line, voicemail and missed-call text for you.

Step 7: Set your hours and who answers when

Your opening hours decide which calls count as after hours. Set them, including Saturday hours and bank holidays, before you decide who answers when.

Then set the call flow. A typical small business flow:

1. In opening hours: ring the team's phones for 20 seconds.
2. No answer, or the line is busy: the AI receptionist answers.
3. After hours: the AI receptionist answers straight away, with the after-hours greeting.

In Line: each number and channel has a workflow, and its Agent step chooses which receptionist answers. Hours are a rule in the workflow, so changing your opening hours changes the routing without touching anything else. A second number, WhatsApp or web chat can each have a different receptionist.

Step 8: Test it with 20 calls

Never point your real calls at an AI receptionist you have not rung yourself. Most providers let you test by chat or by a test call before you go live. Do both.

In Line: the set-up includes a chat test with the receptionist, and the Test section of the agent creator runs a test chat on each channel and shows the checks that must pass before you publish.

Work through the test checklist below. For each call, score four things:

After each failure, change one thing: a fact, a rule, or the greeting. Then call again. Ask a colleague who has not seen the instructions to try it, because you will unconsciously ask the questions you wrote answers for.

Step 9: Go live and watch the first week

Switch on forwarding with the code from step 1, or publish your call flow. Then ring your own number one last time from a phone the AI does not know.

For the first week, read every transcript. It takes ten minutes a day and it is where the real improvements come from. You are looking for four things:

• Questions it could not answer. Add the fact.
• Calls it handled the wrong way. Sharpen the rule.
• Hand-offs that should not have happened, or should have.
• Callers who hung up early. Usually the greeting is too long, or the first question is unclear.

After the first week, switch to a weekly check of hand-offs and a sample of other calls. Our main guide lists the five numbers worth tracking each month.

Common problems and how to fix them

What to do next

• Copy every template at once from the template library.
• Write your voicemail for when everything else fails: business voicemail greetings and receptionist scripts.
• Update your privacy notice: AI receptionists, GDPR and UK law.
• See what an AI receptionist does for your trade on the AI receptionist page, or check pricing.