London has more SEO agencies than anywhere else in the UK, which is exactly what makes choosing one hard. Most "best of" lists are written by agencies that put themselves at number one. We took a different approach: we scored 15 of the strongest SEO agencies in London against six criteria, published the method, and mapped each one to the kind of brief it actually suits. If you would rather browse the full set yourself, our directory of SEO agencies in London holds every agency we have indexed.
We run an independent directory, so our scoring is not affected by whether an agency pays for or has claimed a listing. The list is ordered by overall score, and you will find a section further down that recommends agencies by need: ecommerce, B2B and SaaS, technical, enterprise, local and AI search.
The London SEO landscape in 2026
SEO is the single most requested discipline in our directory: of the 828 UK agencies we index, 482 offer SEO, and 322 of those are in London, far more than any other city. That density is good for choice and bad for clarity, because a boutique technical-SEO team and a 2,000-person network both market themselves with the same three letters.
Ownership is the other shift worth understanding. The market is consolidating: Builtvisible was acquired by Brave Bison in 2025, and Jellyfish has been part of The Brandtech Group since 2023. Several agencies still described elsewhere as independent are not. Across our UK index, 752 of 828 agencies remain independent, 43 are network-owned and 33 are specialists, and which side of that line an agency sits on affects how your account is staffed, priced and escalated. We flag ownership on every entry below.
How we scored this list
Each agency is rated from 0 to 5 on six criteria, shown as stars, and the overall score is a weighted average:
- Industry recognition (20 per cent): wins at the recognised search awards, plus accreditations such as B Corp or Google Premier Partner.
- Client calibre and results (25 per cent): named clients and published, measurable case studies.
- SEO specialism and depth (20 per cent): how focused and deep the agency is across technical SEO, content and digital PR.
- Track record and scale (15 per cent): years trading, team size and stability.
- London presence (10 per cent): a London headquarters scores highest, a substantial office next.
- Transparency (10 per cent): a visible team, clear reporting, reviews and known ownership.
The 15 best SEO agencies in London
1. Impression
Impression
- Recognition5.0
- Clients4.0
- Specialism5.0
- Track record5.0
- London presence4.0
- Transparency5.0
- Founded
- 2012
- Team size
- 120+
- Ownership
- Independent
- HQ
- Nottingham (+ London, Manchester, NYC)
- Specialism
- Technical SEO, content & digital PR
Impression is one of the few UK agencies that genuinely covers the full organic stack in depth: technical SEO, content, digital PR and a dedicated data-science function, rather than badging everything as SEO. Founded in Nottingham in 2012, with offices in London, Manchester and now New York and more than 120 staff, it is a certified B Corp and has stayed independent and founder-led while many peers have been acquired. It has won at the European Search Awards and was named Digital Agency of the Year at the Global Agency Awards. The work skews towards larger, considered brands that want search treated as an accountable performance channel, with reporting to match. If you want one team to own technical fixes, content and authority-building together, and you care about how the agency itself is run, Impression sits at the top of the market. Best for larger brands wanting integrated, accountable search.
2. Re:signal
Re:signal
- Recognition4.0
- Clients5.0
- Specialism5.0
- Track record4.0
- London presence5.0
- Transparency5.0
- Founded
- 2012
- Team size
- 20+
- Ownership
- Specialist
- HQ
- London
- Specialism
- Ecommerce SEO
Re:signal is a London ecommerce SEO specialist rather than a generalist, and the focus shows in a client roster that includes ASICS, FatFace, Expedia and Under Armour. Founded in 2012 with a central London hub and a team of 20-plus, it concentrates on organic revenue growth through technical SEO, content and digital PR for online retailers, and has collected more than 80 awards including wins at the UK, European and Global Search Awards. It is listed and verified on AgencyIndex. For a fashion, retail or direct-to-consumer brand where organic search is a primary revenue line, a specialist like this will usually outperform a full-service agency splitting attention across channels. Best for ecommerce and retail brands.
3. Builtvisible
Builtvisible
- Recognition3.0
- Clients5.0
- Specialism5.0
- Track record5.0
- London presence5.0
- Transparency4.0
- Founded
- 2009
- Ownership
- Network
- Holding group
- Brave Bison
- HQ
- London
- Specialism
- Organic search & digital PR
A long-standing London organic-search specialist founded in 2009, Builtvisible built its reputation on technical SEO, content strategy and digital PR for blue-chip brands including Icelandair, Asda, Aviva, Specsavers, Superdrug and The Very Group. The important change for 2026 is ownership: it was acquired by Brave Bison in March 2025, so despite its independent heritage it now sits inside a listed group. That does not diminish the craft, but if independence matters to your procurement, factor it in. Best for brands wanting senior, strategic organic search who are comfortable with network ownership.
4. The SEO Works
The SEO Works
- Recognition5.0
- Clients4.0
- Specialism4.0
- Track record5.0
- London presence4.0
- Transparency4.0
- Founded
- 2008
- Team size
- 80+
- Ownership
- Independent
- HQ
- Sheffield (+ London)
- Specialism
- SEO, paid search, content, web
With a Sheffield head office and a London office, more than 80 staff and Google Premier Partner status, which places it in the top few per cent of agencies, The SEO Works is a sizeable, accredited search and web agency. It has been named SEO Agency of the Year three times at the UK Digital Growth Awards and has won at the Global Agency Awards, and it spans SEO, paid search, content and web build, which suits briefs that need more than organic alone. The scale and process maturity make it a safer choice for mid-market and ecommerce work that needs reliable delivery rather than a boutique's bespoke attention. Best for mid-market and ecommerce briefs wanting an accredited team.
5. Rise at Seven
Rise at Seven
- Recognition4.0
- Clients5.0
- Specialism4.0
- Track record4.0
- London presence4.0
- Transparency4.0
- Founded
- 2019
- Team size
- 100+
- HQ
- Sheffield (+ London, Manchester, NYC)
- Specialism
- Digital-PR-led search
Founded in 2019, Rise at Seven made its name on digital-PR-led search, the discipline of earning coverage and links that move rankings, and on social-first search across platforms like TikTok. With a London office alongside its Sheffield base, plus Manchester and New York, and a team of 100-plus, it works with high-profile consumer brands including JD Sports, Red Bull and PlayStation, and has collected a large haul of search awards. It is built for visibility and reach rather than quiet technical retainers. If your growth depends on being seen and talked about, this is a different and often more effective model than classic SEO. Best for consumer brands wanting search and earned media to work as one.
6. Found
Found
- Recognition4.0
- Clients4.0
- Specialism4.0
- Track record4.0
- London presence5.0
- Transparency3.0
- HQ
- London
- Specialism
- Technical & international SEO
A central London agency strong in technical and international SEO, Found works across travel, finance, retail and professional services, and positions itself around measurable organic growth rather than quick wins, supported by its proprietary Luminr platform. It has won Best Use of Search at the UK Search Awards alongside its client Bonmarché, as well as European Search Awards and Drum awards. It is an established choice for brands operating across several markets that need search handled at scale, with the team and process to support multi-region work. Best for established brands wanting cross-market organic growth.
7. Jellyfish
Jellyfish
- Recognition4.0
- Clients4.0
- Specialism3.0
- Track record5.0
- London presence4.0
- Transparency4.0
- Founded
- 2005
- Team size
- 2,000+
- Ownership
- Network
- Holding group
- The Brandtech Group
- HQ
- London office
- Specialism
- Enterprise digital
Founded in 2005 and part of The Brandtech Group since 2023, with around 2,000 staff worldwide, Jellyfish is an enterprise digital partner where SEO is one strand within a very broad media, platform and training offer. Long known as one of the most heavily certified Google partners, its strength is scale and breadth across global accounts; the trade-off is that a small or mid-sized brand may be a minor account. It operates at network scale rather than as an independent. Best for large, multi-market organisations.
8. GA Agency
GA Agency
- Recognition4.0
- Clients3.0
- Specialism4.0
- Track record4.0
- London presence5.0
- Transparency5.0
- Team size
- 51-200
- Ownership
- Independent
- HQ
- London
- Specialism
- Multilingual SEO (15 languages)
Listed and verified on AgencyIndex, GA Agency runs an in-house team across 15 languages, which is its genuine differentiator for brands that need SEO executed natively in multiple markets rather than translated after the fact. At 51 to 200 staff it has the capacity for sizeable international programmes without outsourcing the language work. Best for brands running multi-country, multi-language SEO.
9. Distinctly
Distinctly
- Recognition3.0
- Clients3.0
- Specialism4.0
- Track record5.0
- London presence5.0
- Transparency5.0
- Founded
- 2009
- Team size
- 11-50
- Ownership
- Independent
- HQ
- London (Old Street)
- Specialism
- SEO, digital PR & content
An independent London agency in Old Street trading since 2009, Distinctly combines SEO with digital PR and content, and is listed and verified on AgencyIndex. More than a decade of campaigns and a stable mid-size team make it a dependable choice for brands that want an established independent without enterprise pricing. Best for mid-market brands wanting an established independent.
10. ClickSlice
ClickSlice
- Recognition3.0
- Clients3.0
- Specialism5.0
- Track record4.0
- London presence5.0
- Transparency4.0
- Founded
- 2016
- Team size
- Small
- Ownership
- Independent
- HQ
- London
- Specialism
- Shopify / ecommerce SEO
A London ecommerce SEO agency founded in 2016, ClickSlice focuses on Shopify and return-on-investment-led organic growth, and is fronted transparently by its founder. For a Shopify or ecommerce business that wants a focused specialist on a clear performance basis rather than a broad retainer, it is a credible option. Best for Shopify and ecommerce businesses.
11. Kinesso
Kinesso
- Recognition3.0
- Clients3.0
- Specialism3.0
- Track record5.0
- London presence5.0
- Transparency3.0
- Team size
- 500+
- Ownership
- Network
- Holding group
- Interpublic Group
- HQ
- London
- Specialism
- Performance & media with SEO
Part of the Interpublic Group, Kinesso is a large London performance and data business of more than 500 staff, offering SEO alongside media buying, programmatic and data services. SEO sits inside a media-led, technology-driven offer rather than being the headline, which suits large advertisers wanting search inside an integrated account but is less relevant if you want a pure organic specialist. It is listed on AgencyIndex. Best for large advertisers wanting search within an integrated media account.
12. GoUp
GoUp
- Recognition3.0
- Clients3.0
- Specialism4.0
- Track record3.0
- London presence5.0
- Transparency3.0
- Founded
- 2011
- Ownership
- Independent
- HQ
- London (Clerkenwell)
- Specialism
- Search & digital PR
An independent search and digital PR agency in Clerkenwell with a multi-award reputation, GoUp leans towards content-led, campaign-style SEO. It is a strong London independent for brands that want creative, PR-inflected organic work rather than a purely technical retainer. Best for content-led campaigns from a London independent.
13. Whitehat SEO
Whitehat SEO
- Recognition3.0
- Clients3.0
- Specialism3.0
- Track record3.0
- London presence5.0
- Transparency4.0
- Founded
- 2011
- Team size
- Small
- Ownership
- Independent
- HQ
- London (west)
- Specialism
- Inbound & SEO (HubSpot Diamond)
A small independent founded in 2011 in west London, Whitehat pairs SEO with inbound methodology and holds HubSpot Diamond partner status, which signals real strength in content and marketing automation alongside search. The small team suits smaller B2B brands that want SEO and inbound joined up rather than enterprise-scale delivery. Best for smaller B2B brands wanting inbound and SEO together.
14. OmniFound
OmniFound
- Recognition2.0
- Clients2.0
- Specialism4.0
- Track record2.0
- London presence5.0
- Transparency5.0
- Founded
- 2024
- Team size
- 2-10
- Ownership
- Independent
- HQ
- London & Hertfordshire
- Specialism
- Modern & AI search (GEO)
A London boutique founded in 2024, OmniFound is built around modern search: optimising for AI search engines and generative results, known as GEO, as well as classic Google rankings, plus video and local SEO. As a new and small team it is naturally lighter on awards and long track record, which its score reflects honestly, but the focus on where search is heading is its reason to exist. It is listed and verified on AgencyIndex. Best for brands wanting visibility in AI and generative search.
15. Mintense
Mintense
- Recognition2.0
- Clients2.0
- Specialism4.0
- Track record3.0
- London presence4.0
- Transparency4.0
- Team size
- Small
- Ownership
- Independent
- HQ
- London
- Specialism
- Multilingual SEO & paid search
A London independent with more than a decade in multilingual SEO and paid search, Mintense is a small team suited to smaller brands that need international, multi-language search support. It is listed and verified on AgencyIndex. Best for smaller brands needing multi-language SEO.
Find the best SEO agency in London for your situation
A ranking only takes you so far. The right agency depends on what you are actually trying to do:
- Ecommerce and Shopify SEO: Re:signal and ClickSlice are the focused specialists here, with The SEO Works a strong larger option.
- B2B and SaaS SEO: Impression and Distinctly for scale and integration, Whitehat for smaller B2B teams that want inbound and SEO together.
- Technical SEO: Builtvisible and Impression have the deepest technical benches.
- Enterprise and multi-market SEO: Jellyfish, Kinesso, Found and GA Agency have the capacity for global or multi-language programmes.
- Small business and local SEO: ClickSlice, Mintense and the smaller independents will give you more senior attention for the budget.
- Digital PR and link building: Rise at Seven, GoUp, Distinctly and Builtvisible lead on earned coverage and authority.
- AI search and GEO: OmniFound is the clearest specialist building for AI Overviews and generative engines, the fastest-changing part of search.
How much do SEO agencies in London cost?
There is no standard price, and any agency quoting a fixed figure before seeing your site should be treated with caution. As a rough guide, small local or project work tends to start in the low hundreds of pounds a month, mid-market retainers commonly run from around £1,500 to £5,000 a month depending on scope, and enterprise or competitive ecommerce programmes go well beyond that, with some specialist agencies setting minimum monthly fees of £5,000 or more. London rates sit at the higher end of the UK range. These are indicative bands, not quotes; what matters is comparing proposals against a clear brief rather than a headline rate, and understanding exactly what is delivered each month.
SEO and AI search: what is changing in 2026
The most common question we hear now is whether SEO still matters given AI Overviews and tools like ChatGPT. It does, but the work is shifting. Generative engines and AI Overviews increasingly answer queries directly, which rewards brands with strong content, clean technical foundations and genuine authority, and penalises thin, templated SEO. A growing number of agencies now talk about generative engine optimisation, the practice of earning visibility inside AI-generated answers, alongside traditional ranking work. When you brief an agency in 2026, it is worth asking how they are adapting to AI search, not just how they rank pages on Google.
How to choose the right SEO agency
Beyond the ranking, a few practical checks separate a good fit from an expensive mismatch. Ask for case studies in your sector with real metrics, not vanity rankings. Ask who will actually do the work, since boutiques often give senior attention while larger agencies may staff juniors on smaller accounts. Ask how they report and how often. And check ownership: an independent agency and a network-owned one differ in flexibility, pricing and how your account is escalated. If you are running a formal selection or pitch and want an independent hand, our RFP and pitch support service helps brands write the brief, build the shortlist and evaluate responses against the criteria that predict a good partnership.
Common questions
How much does an SEO agency in London cost?
There is no single figure. Small or local work can start in the low hundreds of pounds a month, mid-market retainers often run from roughly £1,500 to £5,000, and enterprise work goes higher. Compare quotes against a clear brief rather than a headline rate.
Is SEO still worth it in 2026, or is it dead?
SEO is not dead, it is changing. AI Overviews and AI search engines are reshaping how organic visibility works, and the agencies adapting fastest build for both classic rankings and AI-generated results. Strong content, technical health and brand authority still drive long-term visibility.
What is GEO, or AI search optimisation?
Generative engine optimisation is the practice of earning visibility inside AI-generated answers, such as Google's AI Overviews and assistants like ChatGPT, rather than only in the traditional blue links. It overlaps heavily with good SEO but puts more weight on authority and clear, well-structured content.
Does it matter if an agency is independent or network-owned?
It can. Network ownership often brings scale and resource, while independence often brings senior attention and flexibility. Neither is better in the abstract; what matters is fit. We label ownership on every entry.
How did we score these agencies?
Each agency is rated on six criteria, set out in the methodology above, with an overall weighted score. Scoring is independent of whether an agency pays for or has claimed an AgencyIndex listing.
You can explore the full, regularly updated list of SEO agencies in London on AgencyIndex, where every listing is editorially reviewed rather than paid for.
