AI receptionists and voice agents in the UK: costs and how they work

Missed calls are lost work for trades, clinics, salons, estate agents and solicitors. An AI voice agent (often sold as an “AI receptionist”) answers the phone, talks naturally, and books, qualifies or routes the caller. Here is how they work, what they cost, and the UK rules you need to know.

How an AI receptionist works

Behind the friendly voice there are usually four parts:

1. Telephony: a phone number (or a diversion from your existing number) that sends the call to the AI.
2. Speech-to-text: turns what the caller says into text in real time.
3. A language model: decides what to say and do, following your instructions and knowledge base (services, prices, opening hours, areas covered).
4. Text-to-speech: speaks the reply in a natural-sounding voice.

The useful part is what happens next: the agent can book into your calendar, create a lead in your CRM, send a text confirmation, or transfer the call to a person. Agencies typically build these on platforms such as Retell AI or Vapi, or on all-in-one CRMs like GoHighLevel.

What it costs

Managed plans from UK providers

Most small businesses buy a managed service: the provider builds the agent, connects your calendar and CRM, and maintains it. Published prices in our directory include:

Prices are as published on each provider’s website when we checked them (11 October 2026). Inclusions differ a great deal (minutes, numbers, integrations, support), so ask each provider what is and isn’t included.

The underlying per-minute cost

Managed plans sit on top of usage-based platforms. As a published example, Retell AI lists pay-as-you-go pricing of $0.07 to $0.31 per minute, depending on the voice, language model and telephony used, plus $2 a month per Retell phone number (pricing page, checked 11 October 2026, US dollars). This is why heavy call volumes can push monthly costs up: always ask how a plan handles minutes beyond its allowance.

The UK rules to know

• Inbound calls and personal data. If the agent records calls or takes callers’ details, you must tell people how their data is used. The ICO’s right to be informed guidance covers what to include. A short message at the start of the call plus your privacy notice is the usual approach.
• Outbound marketing calls. The ICO says automated marketing calls (made by an automated dialling system that plays a recorded message) need the person’s specific consent to that type of call, and live marketing calls must not go to numbers on the TPS or CTPS unless the person has specifically consented (ICO guidance). The ICO notes this guidance is under review following the Data (Use and Access) Act, so take advice before using AI for outbound calling.
• AI voices making outbound marketing calls. An AI agent that places marketing calls and speaks without a live person on the line may well be treated as an automated calling system under PECR (regulation 19), in which case you would need each person’s specific prior consent to that type of call, not just general marketing consent. Until the ICO’s updated guidance is published, assume consent is needed and get legal advice before running any outbound AI calling campaign.

Questions to ask a provider

1. Can I hear a live demo on a real UK number, including a transfer to a person?
2. What happens when the caller has a strong accent, background noise or goes off-script?
3. How many minutes are included, and what does each extra minute cost?
4. Where are recordings and transcripts stored, and for how long?
5. Can I change the script, prices and opening hours myself?
6. What is the notice period, and do I keep my phone number if I leave?

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