Search for what AI automation costs in the UK and you will find a lot of pages that carefully avoid answering. That is not because the answer is unknowable. It is because a vague answer protects the agency's negotiating position. We would rather you could work out whether we are worth talking to before you get on a call.
The short answer
| What you are buying | Typical UK range | Timeline |
|---|---|---|
| A single automation (one workflow, one job) | £1,500 to £4,000 | 1 to 2 weeks |
| A connected set of automations | £4,000 to £12,000 | 3 to 6 weeks |
| A custom AI agent that handles a whole task | £6,000 to £15,000+ | 6 to 10 weeks |
| Ongoing support and improvement | £300 to £900 per month | Rolling |
Those are build costs. Separately, you will pay the underlying platforms directly, and this is where people get caught out.
The running costs nobody mentions
An automation is not free to run. It sits on top of tools that charge you monthly, and an agency that does not tell you this up front is setting you up for an unpleasant surprise in month two.
- ●Automation platform (n8n, Make or Zapier): roughly £20 to £80 per month depending on volume
- ●AI model usage (Claude, OpenAI): usually £5 to £100 per month for a small business, driven by how much text it processes
- ●Messaging (SMS and WhatsApp via Twilio): pennies per message, but it adds up with volume
- ●Any CRM or scheduling tool you do not already pay for
For a typical small business running two or three automations, expect £40 to £150 a month in platform costs on top of any support retainer. If someone quotes you a build price without ever mentioning running costs, ask them directly.
Why the range is so wide
The single biggest cost driver is not the AI. It is the state of the systems you already have.
- ●If your job management software has a clean, modern API, the integration is straightforward and quick.
- ●If your data lives in a spreadsheet, three WhatsApp groups and someone's head, most of the work is untangling that before any automation can be built.
- ●If a human decision genuinely needs to stay in the loop, the build is simpler and cheaper than one that has to handle every edge case unattended.
How to tell whether a quote is fair
A few questions that separate a real proposal from an expensive guess:
- ●What are the running costs, and who pays them directly?
- ●Do I own what you build? Can another developer take it over if we part ways?
- ●What happens when it breaks at 6pm on a Friday?
- ●What is the specific, measurable thing this automation changes, and how will we know if it worked?
- ●What is the smallest useful version we could ship first?
That last one matters most. Anyone who wants to sell you a twelve-week transformation before proving a single automation works is managing their revenue, not your risk.
Beware the hourly rate
Hourly billing puts you and the agency on opposite sides. They are paid more for taking longer; you want it done quickly. For defined automation work, insist on a fixed price against a defined outcome. If the scope genuinely cannot be defined yet, buy a short paid discovery to define it, then a fixed price to build it.
What we charge
We publish our engagement models rather than an hourly rate, for the reason above. A first quick win typically starts at £1,500 and ships in one to two weeks, because we would rather prove the value on something small than ask you to take a large bet on a company you have just met.