B2B marketing in London moves fast, and it is rarely short on competition. Buyers have more options, more tabs open, and less patience for generic messaging. If you rely on a few campaigns a year, or you treat your website as a brochure, growth usually stalls.
A strong B2B agency helps you join the dots. That can mean tightening your positioning, building a content engine that supports sales conversations, running paid media that targets the right accounts, and improving conversion so more of your traffic turns into enquiries. It also means decent tracking, so you can see what is driving pipeline rather than guessing.
Below is our pick of the top 12 B2B marketing agencies in London for 2026. Each entry gives you a quick view of who the agency suits, who it does not, where it is based, and what it actually does, so you can shortlist without wading through sales pages.
1. Munro Agency
Description: Munro Agency is a B2B marketing agency built around lead generation, SEO, PPC, and marketing automation. If you sell to other businesses and need a steady flow of qualified enquiries, you will recognise the way they talk about marketing: practical, measured, and tied back to pipeline.
You can use Munro when you want one team to join up acquisition and conversion, rather than running disconnected campaigns. Their work typically centres on making your website pull its weight, then using paid and organic channels to bring in the right audiences.
If you are also targeting London, Munro lists a London virtual office alongside its Glasgow head office, which can help if you want UK coverage without the London price tag.
Who Are They For: You are a B2B company that wants measurable lead growth through SEO, PPC, and marketing automation. You want a partner that will focus on turning traffic into enquiries, not just “activity”.
Who Are They Not For: You need a brand-only agency with TV-first creative and little performance work. You want marketing without reporting, tracking, or agreed outcomes.
Office Location: Glasgow, Scotland, UK
Year Founded: 2016
Team Size: 11–50 employees
Key Services: Marketing automation, B2B lead generation, SEO, PPC, Conversion rate optimisation, Content marketing
Industries Served: Technology, SaaS, Professional services, Consulting, Sustainability
Case Studies: View all case studies
2. Earnest
Description: Earnest is a B2B marketing agency with offices in London and New York. If your challenge is making complex offers feel clear and worth attention, they lean heavily into strong messaging, campaign thinking, and content that does not sound like corporate filler.
You will get the most from Earnest when you want brand and demand to work together. Their portfolio shows a mix of campaigns, content, and digital work, which suits teams trying to improve performance without losing the bigger story.
Who Are They For: You want B2B brand and campaign work that supports demand and pipeline. You have an internal team and want an agency to sharpen strategy, messaging, and creative execution.
Who Are They Not For: You only want low-cost channel management with minimal strategic input. You need a pure lead factory with no interest in positioning or creative.
Office Location: London, England, UK
Year Founded: 2009
Team Size: 11–50 employees
Key Services: B2B brand strategy, Campaign strategy, Content marketing, Digital campaigns, Paid media support
Industries Served: Technology, Telecoms, Financial services, Professional services, B2B services
Case Studies: View all case studies
Description: Velocity Partners is a B2B agency known for positioning, messaging, and content that helps buyers “get it” quickly. If you sell something technical or high-consideration, they focus on turning complexity into a story your sales and marketing can actually use.
Their work page is a useful signal of how they think: opinionated, direct, and tied to outcomes like demand and pipeline. You would usually bring Velocity in when you need a clearer narrative, stronger creative, and content that supports performance work rather than sitting on the shelf.
Who Are They For: You are a B2B company that needs sharper positioning and content that supports growth. You want senior thinking, not a junior production line.
Who Are They Not For: You only want cheap delivery for a single channel. You need an agency that will follow your brief exactly without challenging it.
Office Location: London, England, UK
Year Founded: 2000
Team Size: 51–200 employees
Key Services: Positioning and messaging, B2B content marketing, Creative and design, Campaign development, Performance support
Industries Served: Technology, SaaS, Cybersecurity, Data, Professional services
Case Studies: View all case studies
Description: The Marketing Practice is a B2B marketing agency with a strong focus on demand generation and account-based approaches. If you run enterprise sales cycles and need marketing that aligns tightly with revenue teams, their offer is built for planning, orchestration, and delivery at scale.
They are a better fit when you want an integrated programme rather than disconnected campaigns. Their work and case studies are typically framed around commercial impact, which suits teams that need structure, cadence, and consistent execution across markets.
Who Are They For: You are an established B2B company running complex buying cycles and multi-touch journeys. You want demand generation that is planned, measured, and repeatable.
Who Are They Not For: You are a very early-stage startup needing quick, lightweight support. You want a one-off campaign with no ongoing programme behind it.
Office Location: London, England, UK
Year Founded: 2002
Team Size: 201–500 employees
Key Services: Demand generation, ABM programmes, Paid media, Content production, Marketing operations support
Industries Served: Enterprise technology, SaaS, IT services, Professional services, Telecoms
Case Studies: View all case studies
5. Gripped
Description: Gripped is a B2B digital marketing agency in London that leans into pipeline, revenue, and practical execution for SaaS and tech. If you need demand generation that connects ads, landing pages, and reporting, they position themselves around growth outcomes rather than vanity metrics.
They are also clear about showing results and examples on their site. If you want an agency that will run paid media, improve conversion, and keep the focus on qualified opportunities, Gripped is a sensible shortlist option.
Who Are They For: You are a B2B SaaS or tech firm that needs more qualified pipeline. You want an agency that can run demand gen and improve conversion on the site.
Who Are They Not For: You want brand-only work with no performance targets. You sell mostly to consumers and need ecommerce-first marketing.
Office Location: London, England, UK
Year Founded: 2017
Team Size: 11–50 employees
Key Services: Demand generation, Paid search, Paid social, SEO, Conversion rate optimisation
Industries Served: SaaS, Technology, IT services, Cybersecurity, AI
Case Studies: View all case studies
6. Transmission
Description: Transmission is a global B2B marketing agency that talks openly about connecting brand and demand. If your marketing feels fragmented across teams or regions, their positioning is built around designing a joined-up experience from first touch through to sales activation.
They show a broad range of work on their site, which is useful if you want a partner that can handle strategy, creative, and multi-channel delivery. Transmission can be a good fit when you need scale and consistency, without losing the quality of thinking.
Who Are They For: You are a B2B organisation that needs joined-up brand and demand across multiple channels. You want an agency with experience running larger, multi-stakeholder programmes.
Who Are They Not For: You only want support on a single small channel with minimal coordination. You want a low-touch supplier rather than a partner that challenges decisions.
Office Location: London, England, UK
Year Founded: 2013
Team Size: 201–500 employees
Key Services: B2B strategy, Integrated campaigns, Content marketing, Sales activation, Digital experience
Industries Served: Technology, SaaS, Professional services, Industrial, Energy
Case Studies: View all case studies
7. True
Description: True is a London B2B marketing agency that focuses on building B2B brands and running campaigns that people actually notice. If your marketing feels too “performance-only” and it is not helping sales conversations, True is geared towards fixing the brand story and then delivering it through creative and media.
They are also part of BBN, which matters if you need broader reach while keeping a B2B-specialist lead agency. Practically, you use True when you want sharper messaging, stronger creative, and media that is planned to support real business outcomes, not just impressions.
Who Are They For: You are a B2B team that needs stronger positioning and campaigns that support demand. You want a London agency that can handle both creative and media with a B2B lens.
Who Are They Not For: You only want tactical lead gen delivery with no brand work. You need a small niche shop for one channel only and nothing else.
Office Location: London, England, UK
Year Founded: 2012
Team Size: 11–50 employees
Key Services: B2B brand strategy, Integrated campaigns, Creative development, Media planning and buying, Audience insight
Industries Served: Technology, Financial services, Professional services, Industrial, B2B services
Case Studies: View all case studies
Description: Gravity Global positions itself as a brand-to-demand consultancy, with a long-standing B2B focus. If you need to connect brand strategy to demand generation in complex markets, they offer planning, creative, and delivery across channels.
Gravity is often a fit when you want depth across strategy, research, and execution, rather than a narrow specialist. Their work page shows a wide range of projects, which helps if you are comparing agencies for multi-market support.
Who Are They For: You are a B2B brand in a complex market that needs joined-up brand and demand work. You want strategy, research, and execution from one team.
Who Are They Not For: You only want a small SEO retainer with limited change elsewhere. You need a micro agency built purely for early-stage startups.
Office Location: London, England, UK
Year Founded: 2009
Team Size: 201–500 employees
Key Services: B2B brand strategy, Integrated campaigns, Content and creative, Paid media planning, Digital experience
Industries Served: Aerospace, Manufacturing, Technology, Financial services, Professional services
Case Studies: View all case studies
9. The Croc
Description: The Croc is a London-based B2B marketing agency that focuses on “brand-to-demand”, which is a helpful way of describing the gap many B2B teams struggle with. If your brand work and your lead work live in different places, they aim to connect the two so marketing feels consistent from awareness through to sales activation.
Their work section is geared around showing how they approach strategy, creative, and performance as one system. The Croc can suit teams that want strong creative, but still need demand outcomes to be taken seriously.
Who Are They For: You want brand and demand to work together, with creative that supports commercial goals. You are running B2B campaigns across multiple touchpoints and need consistency.
Who Are They Not For: You only want a production supplier for assets with no strategic input. You want a purely inbound SEO agency and nothing else.
Office Location: London, England, UK
Year Founded: 1990
Team Size: 51–200 employees
Key Services: B2B strategy, Integrated campaigns, Creative development, Media planning, Demand generation
Industries Served: Technology, Enterprise services, Industrial, Financial services, Professional services
Case Studies: View all case studies
10. Iris Worldwide
Description: Iris is a global creative agency founded in London, with a large team across multiple offices. If you want B2B work that borrows the best habits from strong consumer creative, Iris can be relevant, especially when you need campaigns that carry across brand, social, and content.
Their work page is broad and campaign-led, which is useful if your brief is bigger than lead volume alone. Iris can be a good fit when you need standout creative execution, plus the strategic thinking to tie it back to business goals.
Who Are They For: You want an established agency with strong creative and multi-channel campaign experience. You have budget and internal buy-in to run bigger ideas properly.
Who Are They Not For: You need a small specialist for quick tactical support only. You want a narrow performance-only agency with no creative capability.
Office Location: London, England, UK
Year Founded: 1999
Team Size: 501–1,000 employees
Key Services: Campaign development, Brand strategy, Content production, Social media, Digital experience
Industries Served: Technology, Consumer brands, Professional services, Entertainment, Retail
Case Studies: View all case studies
11. Fabrik Brands
Description: Fabrik is a London branding agency that supports B2BB and B2C work, with a strong emphasis on strategy, naming, and identity. If your B2B growth problem is really a clarity problem, such as confusing proposition, messy messaging, weak positioning, Fabrik helps you tighten the basics before you spend more on media.
Their portfolio is the best place to assess fit, because the work is visual and practical. Fabrik suits teams that want brand foundations that make marketing and sales easier to run, especially for complex services or products.
Who Are They For: You need sharper positioning, naming, or identity to support B2B growth. You want brand work that makes your website and campaigns easier to run.
Who Are They Not For: You only want lead gen delivery without any brand work. You need a pure PR agency focused mainly on media relations.
Office Location: London, England, UK
Year Founded: 1995
Team Size: 11–50 employees
Key Services: Brand strategy, Naming, Visual identity, Messaging, Website design support
Industries Served: Technology, Professional services, Finance, Education, B2B services
Case Studies: View all case studies
12. Publicis Pro
Description: Publicis Pro is Publicis Groupe’s B2B-focused agency in London, built to support organisations that need structured B2B marketing across strategy, creative, influence, and commerce. If you want the backing of a major network but still need a dedicated B2B offer, this is the point of the brand.
Their work page is positioned around B2B campaigns, which helps you judge the kind of output you would get. Publicis Pro tends to suit bigger teams that want breadth, plus access to adjacent capabilities across the wider group when needed.
Who Are They For: You are a larger B2B team that wants a B2B specialist within a global network. You need strategy and creative that can scale across regions or business units.
Who Are They Not For: You want a small boutique agency with a very hands-on founder-led style. You need low-budget support for a narrow tactical brief.
Office Location: London, England, UK
Year Founded: 1999
Team Size: 51–200 employees
Key Services: B2B strategy, Content and creative, Demand generation, Brand engagement, Research and insight
Industries Served: Technology, Financial services, Professional services, Industrial, B2B services
Case Studies: View all case studies
How We Chose and Ranked These Agencies
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London relevance and delivery footprint: Prioritised agencies with a clear London office or established London presence, and a track record of serving UK and EMEA B2B teams from London.
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B2B specialism, not “everything for everyone”: Ranked higher the agencies that clearly position around B2B marketing, including demand generation, ABM, B2B content, and sales enablement, rather than general consumer-led digital services.
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Proof you can check quickly: Looked for publicly available evidence such as work pages, case studies, client examples, and clear explanations of what they actually do, not just vague claims.
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Practical growth capability: Favoured teams that can connect strategy to execution across the channels B2B buyers use, for example SEO, paid search, paid social, conversion, content, and marketing ops, plus measurement that ties back to pipeline.
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Buyer clarity and commercial fit: Considered how clearly each agency explains who they are for, typical engagement style, and what you get for your spend, so the list reflects options you could realistically shortlist and hire in 2026.
Where to Go from Here
Most B2B teams do not need more marketing activity. They need a clearer plan, better conversion on the site, and campaigns that attract the right buyers consistently. The agencies in this list sit at different points on that spectrum, from brand and messaging specialists to demand gen teams built around performance.
If your priority is B2B lead generation through SEO, PPC, paid social, conversion rate optimisation, and marketing automation, talk to Munro Agency. Share your targets, your market, and what is currently not working, and they will help you map out practical next steps and a measurable plan.
FAQs
A B2B marketing agency helps you market and sell to other businesses. It typically supports lead generation, positioning, content, paid media, and conversion, with reporting tied to pipeline.
Start with your goal, for example more qualified leads, better conversion, or stronger messaging. Then shortlist agencies with proven B2B work, clear services, and a process that matches your pace, budget, and sales cycle.
A good agency should cover the basics that drive pipeline: messaging, content, website and landing pages, SEO, paid search, paid social, and conversion rate optimisation. It should also handle tracking and reporting so you can see what is working.
Paid campaigns can show early performance signals in a few weeks, while SEO usually takes a few months to build. Most teams see the best results when they improve conversion and tracking early, then compound gains over time.
Ask what they would prioritise in the first 30 days and how they measure success. Also ask who will do the day-to-day work, how reporting works, and how they connect marketing activity to pipeline and revenue.
