Best AI SEO Agencies in London (2026): Compared on Client Results

Rank Dough compared 8 AI SEO agencies working in London, ours included, and charted 8 sites in Ahrefs: 6 agency clients and 2 sites from my earlier roles. Only 1 of the 8 sites is up on a year ago, and only 2 of the 7 London agencies give dates you can check a claim against.

Not sure which client story is closest to your business? Take the quick check. Pick one and the matching section opens, with a question to put to any agency.

Which London AI SEO agencies did we compare?

We compared 8: Croud, Elixirr Digital, Reboot Online, Kaizen, Passion Digital, Position Digital, BE VISIBLE and Rank Dough. They run from two firms that each state 600+ staff to small teams, so the first table shows each agency’s client evidence and the second shows scale, price and awards. Rank Dough is ours and is not London based, so it is disclosed and checked on the same evidence as the rest.

An agency made the list only when we read three things on its own pages: a London base, a named client and a result with a number. Two of the seven, Elixirr Digital and BE VISIBLE, list London without a street address, and the table says so.

We used the same checks in our Dublin list and our UK travel AI SEO agencies list, so you can compare agencies across all three.

Source: agency websites and case study pages, read 2 November 2026; agency award pages and the Rank Dough home page, read 3 November 2026; Ahrefs Site Explorer, estimated organic visits a month, pulled 2 November 2026. Evidence label: Backed means Ahrefs shows the claimed change in the claimed window; Partly means the direction fits but dates, domain or metric cannot be matched; Not checkable means the claim is not a traffic figure; Not charted means no client domain was named.

What happened to their clients’ organic traffic?

We pulled estimated monthly organic visits for each client’s whole domain from Ahrefs Site Explorer on 2 November 2026. Every chart runs to October 2026, so the last 12 months compare October 2025 with October 2026.

Source: Ahrefs Site Explorer, estimated organic visits a month, subdomains included, pulled by Rank Dough on 2 November 2026.

1 of the 8 sites grew over the last 12 months: Thorne, by 7%. The other 7 fell: Decentriq by 7%, Hostelworld by 23%, Gozney by 33%, TUI by 34%, Aer Lingus by 41%, MS Trust by 46% and Shoosmiths by 63%.

Most of the case studies describe 2025. Most of the falls happened in 2026. That is a pattern in 8 sites, not a finding, and I have not tested why.

Change compares October 2026 with October 2025 for the same domain. Domains: gozney.com is named in Kaizen’s case study; thorne.com, mstrust.org.uk, tui.co.uk, shoosmiths.com and decentriq.com are matched to the client name. Estimated organic visits a month, Ahrefs Site Explorer, pulled 2 November 2026; October 2025 column checked again on 3 November 2026.

One method note. Ahrefs estimates traffic from rankings and search volumes for the whole domain, so it can disagree with a client’s own analytics, and it cannot see AI assistant sessions at all. Where the two differ, the agency’s figure may still be right, but it needs dates and a domain to be checked.

What do Croud’s clients show?

Thorne is a US supplement brand. Croud reports 30% more organic revenue year on year, 22% ahead of target, and a 66% AI mention rate on its own brand tracker. No dates are given.

Ahrefs shows Thorne’s 2025 average at 315,229 visits a month, 1.4 times its 2024 average of 220,796. It peaked at 482,641 in April 2026 and had 323,945 in October, 7% above a year earlier. It is the only site here that is up.

What do Elixirr Digital’s clients show?

MS Trust is a UK multiple sclerosis charity. Elixirr reports 4,061 AI sessions, up 907.7% year on year, and AI Overview coverage that grew from 1 tracked keyword in April to 42 in October 2025. Ahrefs cannot see AI sessions.

What it can see is the whole site: 46,885 visits in October 2024 and 84,209 in October 2025, 1.8 times. The site peaked at 107,194 in November 2025 and had 45,880 in October 2026, down 46%.

What do Reboot Online’s clients show?

TUI is a holiday company, and the case study covers its family holidays. Reboot reports TUI ranked first in AI answers for “best family holiday provider” with a 63% share of voice, up from 46% to 78% across its tracked prompts. Those are AI visibility measures, so a traffic chart cannot confirm or deny them.

The chart is context. tui.co.uk peaks each summer and each January. June 2026 had 6,954,313 visits against 13,239,146 in June 2025, and October 2026 is 34% below October 2025.

What do Kaizen’s clients show?

Gozney makes pizza ovens. Kaizen names the domain, Gozney.com, and reports 70% more UK non-brand traffic year on year, 116% more top 3 rankings, 1,900% more LLM traffic and 32% more global organic revenue. No start month is given.

Ahrefs cannot split UK non-brand traffic out of a whole domain. The whole domain went from 210,121 visits in June 2024 to 309,786 in June 2025, 1.5 times. It had 157,083 in October 2026, 33% below a year earlier.

What do Passion Digital’s clients show?

Shoosmiths is a UK law firm, and the case study covers its serious injury practice. Passion reports 33% more sitewide organic clicks year on year, 213 new page one rankings and 21 new AI Overview features, shown at the client’s conference in January 2025.

Ahrefs shows the domain from June 2023. July to December 2024 averaged 22,439 visits a month against 12,068 a year earlier, 1.9 times. The site peaked at 28,644 in May 2025 and had 5,041 in October 2026, down 63%.

What do Position Digital’s clients show?

Decentriq is a data clean room company. Position Digital gives the window, April to October 2025, and the numbers: organic traffic from 1,385 to 2,233, up 61%, and AI citations from 14 to 45.

Ahrefs shows 1,311 visits in April 2025 and 2,376 in October 2025, 1.8 times, so the claim holds in the stated months. The site peaked at 2,908 in March 2026 and had 2,220 in October, 7% below a year earlier.

What do BE VISIBLE’s clients show?

BE VISIBLE’s Caliber case study reports 28% more organic clicks in three months, to 4,780 on 1.24 million impressions, and a first enterprise lead from AI search after two months. It does not name Caliber’s domain or a start month, so there is nothing we can chart without guessing. Not charted stays not charted.

What do Rank Dough’s results show?

Rank Dough has no London client we can chart yet. The two sites below are my work before Rank Dough, so I do not count them as agency clients.

At Aer Lingus I worked through iProspect from January 2021 to March 2022. Traffic went from 88,779 to 440,720 visits a month, 5.0 times, while travel reopened, so I do not credit that to SEO alone. At Hostelworld I was in-house from May 2022 to January 2025, and whole-site traffic rose 19%. Both are down on a year ago: Aer Lingus by 41% and Hostelworld by 23%.

What do these charts tell a London business?

Read together, the 8 charts show five patterns a London business should expect from SEO and AI search work. Each comes from the charts above. They are my reading of the data, not tested rules.

Which of these client stories is closest to your business?

Pick the story closest to your business. The matching section opens below, with a question to put to any agency.

How should you choose an AI SEO agency in London?

Four checks follow from the data above. They are my judgement. I have not tested whether they predict results.

1. Ask for the client’s domain and the month the work started. Only Kaizen named a domain and only Position Digital and Elixirr Digital gave dates.
2. Check the claim in Ahrefs or ask for a Search Console export. Decentriq’s rise shows in the stated months; TUI’s share of voice cannot be checked from traffic at all.
3. Ask what happened after the case study ended. 7 of the 8 sites are down on a year ago, including Shoosmiths by 63% and MS Trust by 46%.
4. Match the client to your business, not the agency to your size. A pizza oven brand, a charity, a law firm and a data company need different work, and the closest client tells you more than the headcount.

Price and scale matter too. Croud and Elixirr Digital each state 600+ staff and publish no prices. Three show a number: Reboot Online from £2,500 a month, Position Digital from $2,000 a month and Passion Digital budget bands from under £3k to £10k+. Ask the others for a range before the first call.

Awards help less than a dated case study. 5 of the 7 London agencies show a win on their own site, but Croud’s and Passion Digital’s search awards are from 2023, Kaizen’s is from 2018 and Elixirr Digital’s is an employer award. Position Digital shows no award and has the one claim Ahrefs fully backs. Ask which client and which year an award covers, then check that client the same way.

What do people ask about AI SEO agencies in London?

Who is Rank Dough, and what are the limits of this list?

Rank Dough is a small team. Our site names 2 people, Roman Sadowski and David Mason. We trade as Fortunata and work from Loughrea, Co. Galway, with a UK address in Essex, not London. We put ourselves in this list because London businesses compare us with London agencies.

I have worked in search since 2004. The record charted here is Aer Lingus at iProspect and Hostelworld in-house. Neither was a Rank Dough engagement. The awards on our home page come from the same work: Best Use of Search and Travel and Tourism for Aer Lingus, and Best Blog for Workplace from Meta. This article is published by Rank Dough, which appears in the table, so check every claim against the named domain in Ahrefs.

The limits are clear. Traffic is estimated at domain level from one pull on 2 November 2026. We did not measure sales, leads, AI sessions or AI citations. There is no before-and-after test, 5 of the 6 other-agency domains are matched to the client name rather than linked, start dates are unknown for 4 of the 6, and each agency is judged on the one client it chose to publish. If you work in Ireland, our Dublin list uses the same method. We also checked Rank4AI (Colchester base), Digitaloft (Kendal and Manchester), Blue Array (Reading), Re:signal (remote), Rise at Seven (Manchester head office), Builtvisible, NetTrackers, Brainlabs, Semetrical, Impression and Exposure Ninja, and left them out because we could not read a London base, or a named client with an AI search result, on their pages.

Sources

• Ahrefs Site Explorer, estimated monthly organic traffic for 8 client domains, pulled by Rank Dough on 2 November 2026
• Position Digital, Decentriq case study, April to October 2025 figures
• Google Search Central, Do you need an SEO?