Only 13% of UK SME Websites Have an llms.txt File: What Our Research Found

Last updated: March 2026

We checked 30 UK small and medium-sized business websites across nine industries to see whether they had an llms.txt file in place. The short answer: almost none of them did.

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TL;DR

• Only 4 out of 30 UK SME websites we checked had an llms.txt file (13.3%)
• Marketing agencies had the highest adoption at 50% — still only half
• Law firms, estate agents, dentists, personal trainers, restaurants and retailers: 0%
• Accountancy firms showed early signs of adoption at 22%
• llms.txt is still an emerging convention with no formal standard, but adoption is beginning to appear in digitally aware sectors

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What is llms.txt?

llms.txt is a plain text file placed at the root of a website (e.g. yoursite.co.uk/llms.txt) that provides a structured summary of what the site is about, who runs it, and what its key pages cover. It is designed to help large language models — the technology behind ChatGPT, Claude, Perplexity and others — understand a website more quickly and accurately.

The concept was proposed in late 2024 and has since gained traction among developers and some forward-thinking businesses. It is not yet a formal web standard, and there is no confirmed evidence from any AI platform that the presence of an llms.txt file directly influences whether a business gets cited or recommended. It remains an emerging convention.

That said, the logic behind it is straightforward: if AI systems are going to read your website, giving them a clear summary of what you do and how your content is structured may help reduce the chance of misinterpretation. Whether that translates into measurable visibility improvements is still an open question.

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What we checked

We selected 30 UK SME websites at random across nine industries:

• Accountancy (9 sites)
• Marketing agencies (4 sites)
• Estate