ToolsFree tool · UK prices, sourced and dated

AI running cost calculator

Move the sliders. The monthly cost updates as you go.

What should the AI do?
calls

The calls you want it to pick up.

03,000+
min

Booking an appointment is usually two or three minutes.

115+
How capable should the AI be?
See the working: range, line items, sources and supplier questions

The range

Low£82.41
Typical£106
High£142

Low to high uses the cheapest to dearest voice platform (Vapi, Retell, ElevenLabs) and speech rate. Your volumes stay fixed. All figures exclude VAT.

Line by line, typical

  • Model usage£41.57Language model at $0.0625 a minute × 900 minutes
  • Telephony£9.24Twilio inbound at $0.01 a minute, plus a $3.50 number
  • Voice platform and speech£54.88Voice platform $0.055 and speech $0.0275 a minute

Per call: 35.2p · per minute, all in: 11.7p

What drives the cost

  • 52% of the cost is voice and speech.
  • Call length drives 98% of it: every extra minute on the average call adds £34.37 a month.
  • With Simple AI it would be £66.11. Often fine for answering and booking; test it on your own calls.

Comparisons

Against a person: an employed receptionist costs about £2,050 a month in salary, about £2,400 with employer costs (ONS median £24,678). Against a subscription: self-serve AI receptionists cost £25 to £99 a month. Cross-check: at the UK guide figure of 15p to 20p a minute for an all-in voice stack, 900 minutes would be £144 to £189.

Ask a supplier before you sign

  • Who pays the AI and phone bills? You directly at cost, or the supplier with a markup.
  • Is usage capped per day and per month, and have they seen the cap stop the system?
  • What is included, and what does each extra call cost above it?
  • Per minute or per call? Per-minute billing punishes long calls.
  • Which AI model runs which step, and can it be changed without a rebuild?
  • Who owns the accounts, prompts and workflows if you leave?

Change the details

AI model
Who rings whom

Receptionist pay is the ONS median salary, £24,678, over a 37.5-hour week. The call value is the illustrative plumbing job from our receptionist guide; use what one of your calls is worth.

Excluding VAT, the one-off build and the time someone spends checking exceptions.

Where these numbers come from

Each unit price below appears in one of our published cost guides, which cites the vendor page it was read from, or was read on the vendor’s own pricing page on 14 October 2026 for this calculator. Prices are list prices, pay as you go, excluding VAT. Dollar and euro prices are converted at the Bank of England spot rates for 11 September 2026 ($1.3530 and €1.1649 to the pound), the rates our guides use; you can change them under Assumptions.

Models, per million tokens

  • Small tiergpt-6-luna $0.10 / $0.50 · Claude Haiku 5.5 $0.10 / $0.50 · gpt-5.4-mini $0.75 / $4.50
    Input / output. Guide: What an AI agent costs to build and run. Original: OpenAI API pricing and Anthropic pricing, read 14 Sep 2026. Low, typical and high use the three models in that order.
  • Mid tiergpt-6.1-sol $2 / $10 · Claude Sonnet 5.5 $2 / $10 · gpt-5.4 $2.50 / $15
    Same guide. Original: Anthropic and OpenAI pricing pages, read 15 Oct 2026.
  • Frontier tierClaude Opus 5.5 $4 / $20 · gpt-5.5 $5 / $30 · Claude Fable 5.1 $10 / $50
    Same guide and vendor pages, read 15 Oct 2026.

AI voice, per minute of call

  • Voice platformVapi $0.05 · Retell $0.055 · ElevenLabs Agents $0.08
    Guide: AI receptionists in the UK, section "What building your own actually costs, per minute". Original: Vapi, Retell, ElevenLabs pricing pages, read Sep 2026.
  • Language model, per minuteSmall $0.003 · mid $0.045 to $0.08 · largest $0.16
    Same guide, from Retell’s pricing page, read Sep 2026. Typical mid uses the midpoint, $0.0625.
  • Text to speech$0.015 (platform voices) to $0.04 (ElevenLabs)
    Same guide and Retell page. Typical uses the midpoint, $0.0275.
  • Cross-check: all-in AI voice stack15p to 20p a minute
    AI Agency Plus, How much AI automation costs in the UK (Jul 2026), as cited in our agent cost guide. Shown beside phone results; not used in the sum.

Telephony and messaging, UK

  • Twilio voiceInbound $0.0100/min · outbound to mobile $0.0305 · to landline $0.0158 · local number $3.50 a month
    Twilio Voice pricing, United Kingdom, read 14 Oct 2026, shown in US dollars. Also in our agent cost and AI receptionist guides (read Sep 2026).
  • Twilio SMSOutbound $0.056 · inbound $0.0075 · mobile number $2.50 a month · alphanumeric sender ID free
    Guide: What an AI feature costs to run. Original: Twilio SMS pricing, United Kingdom, read 14 Sep 2026.
  • WhatsApp via TwilioTwilio fee $0.005 per message, in or out · Meta UK fee $0.022 per service message (typical and high) · $0 (low)
    Researched for this calculator, 14 Oct 2026. Twilio WhatsApp pricing ("pricing current as of September 2026") lists the UK Meta fee at $0.022 for service and utility messages and $0.0635 for marketing templates. Meta’s pricing documentation still describes service messages inside the 24-hour window as free, so the low figure uses $0. Marketing templates are not modelled.

Platform and hosting

  • n8n CloudStarter €20 a month, 2,500 executions · Pro €50, 10,000 executions (annual billing)
    Guide: What an AI agent costs to build and run. Original: n8n pricing, read 14 Sep 2026.
  • Vercel Pro$20 a month, including $20 of usage credit
    Researched for this calculator: Vercel pricing, read 14 Oct 2026. The free Hobby plan is for non-commercial use only, so it is not offered here.

Comparisons

  • Employed receptionist£24,678 median salary · about £2,050 a month · about £2,400 with employer costs
    Guide: AI receptionists in the UK. Original: ONS, Annual Survey of Hours and Earnings 2025, full-time median for receptionists.
  • Break-even: receptionist hour£12.66 an hour
    The ONS median receptionist salary above, £24,678, over the 37.5-hour week the same guide uses, 52 weeks. Salary only; with employer costs it is about £14.77.
  • Break-even: staff hour£20.44 an hour (ONS full-time median, £766.60 a week)
    Guide: AI training for staff: UK cost, which takes the median over 37.5 hours. Original: ONS, Employee earnings in the UK: 2025 (Oct 2025, April 2025 data).
  • Break-even: value of a recovered call£250
    The illustrative plumbing job in the worked examples of our AI receptionist guide. Not a market figure: put in what one of your calls is worth.
  • Self-serve AI receptionist subscriptions£25 to £99 a month
    Same guide; providers’ own pricing pages, read Sep and Oct 2026.
  • Invoices keyed by hand9 minutes each at a loaded £28 an hour
    Guide: AI document processing for a UK SME, worked example. The guide labels these figures illustrative; you can change both under Assumptions.
  • Claude Team seat$25 a month billed monthly, $20 billed annually (Standard seat)
    Guide: Claude Team plan for a UK business. Original: Anthropic plans and pricing, read 24 Sep 2026.

Token counts and other assumptions

  • Chat conversation5 turns, 6,000 input and 800 output tokens
    The stated assumption in the worked inbound example of our agent cost guide: the system prompt and history are resent each turn.
  • Email triage3,000 input and 300 output tokens per email; a draft adds 3,000 and 500
    3,000 / 300 is the per-call assumption in the agent guide’s outbound example; our inbox guide describes a few thousand tokens per message. The draft size and the 50% share needing a reply are our assumptions, editable.
  • Document pageAbout 1,600 tokens per scanned page
    Anthropic vision documentation, read 14 Oct 2026: a page image is capped at about 1,560 visual tokens on standard-resolution models. Instructions (1,000 tokens) and output (400) are our assumptions, consistent with the document guide’s "a few thousand tokens of input and a few hundred of output".
  • Internal request2,000 input and 300 output tokens · 21 working days
    Token sizes from the worked example in What an AI feature costs to run. 21 working days a month is our assumption.

Not included: VAT, the build, the time a person spends reviewing exceptions, prompt caching and batch discounts (which lower the model line), data-residency uplifts (which raise it by about 10%), and volume discounts. Prices change; the date is the thing to check.

£105 a monthSee estimate
The short answer

What does it cost to run AI in a UK business?

For most UK small businesses, tens to low hundreds of pounds a month, excluding VAT and the one-off build. The AI model itself is usually the smallest part: a five-message written conversation costs about 1.5p. What moves the bill is how the AI talks to people. A text message costs about 4p, a WhatsApp reply about 2p, and a minute of an AI phone call roughly 6p to 16p once the voice and phone line are included. So 300 three-minute calls a month cost about £80 to £140 to run, while 400 website chats cost about £20 to £25 including the system they run on.

Questions

Questions people ask about AI running costs

How much does an AI phone receptionist cost to run per minute in the UK?

Built on a voice platform, about 6p to 16p a minute on small and mid-priced models: the platform at $0.05 to $0.08 a minute, the model at $0.003 to $0.08, speech at $0.015 to $0.04, and Twilio UK inbound carriage at $0.01. The most capable AI models raise it to roughly 18p to 22p. If all you need is calls answered and booked, a subscription at £25 to £99 a month is usually cheaper and quicker; our AI receptionist guide compares thirteen of them.

Is the AI model the expensive part?

Rarely. One UK text message at $0.056 costs more than a whole five-turn conversation on a small model. Messaging, voice minutes and the platform usually outweigh the model, unless every request goes to the most capable models, which multiplies the model line by up to forty for routine work.

What does WhatsApp cost for an AI assistant?

Through Twilio, $0.005 per message in either direction plus Meta’s fee. Twilio’s calculator, current as of September 2026, shows a UK Meta fee of $0.022 per service message and per utility template outside the 24-hour window, and $0.0635 per marketing template. Meta’s own documentation still describes service replies as free, so the calculator’s low figure uses $0. Read the current rate card before you commit.

How accurate is this calculator?

The unit prices are the vendors’ list prices on the dates shown, so the arithmetic is exact for the assumptions you set. The assumptions are where the uncertainty is: call length, conversation length and document size. The low and high figures vary the unit prices, not your volumes, so if your volumes are uncertain, run it twice.

Does it include VAT and the cost of building the AI?

No. It shows running costs excluding VAT. Building the agent is a separate one-off: £500 to £15,000 for a single agent at UK agencies according to published 2026 prices, more for several connected agents. Someone also has to review the exceptions, and that time is not in the figure.

Use it on your site

Cite or embed this calculator

Free to cite and embed. Please keep the credit link; it is how readers find the sources.

Citation

Augustova (2026). AI running cost calculator for UK businesses. Unit prices read 14 September and 14 October 2026. https://www.augustova.co.uk/tools/ai-running-cost-calculator

Embed
<iframe src="https://www.augustova.co.uk/tools/ai-running-cost-calculator?embed=1" title="AI running cost calculator for UK businesses" width="100%" height="1150" style="border:0;max-width:1120px" loading="lazy"></iframe>
<p style="font-size:13px">AI running cost calculator by <a href="https://www.augustova.co.uk/tools/ai-running-cost-calculator">Augustova</a>. Unit prices sourced and dated on the calculator page.</p>

Prices are vendors’ list prices on the dates shown, excluding VAT. This calculator is an estimate, not a quote.