Best B2B Demand Generation Agencies in London (2026), by What They Are Best For

How this list works

There is no overall number one. Agencies are grouped by what they are best for, and listed alphabetically inside each group, because the right demand generation agency depends on your stage, budget and channels, not on who wrote the list.

Kiin publishes this list and is on it. Kiin appears only in the category where its own published facts put it. Every fact about another agency was read from that agency's own website on 30 October 2026 and is checkable from the scorecard below; where a site does not state something, the entry says so. Nobody paid to appear.

The shortlist by need

• An outsourced SaaS marketing team: Rocket SaaS
• Series A to D SaaS wanting paid, SEO and ABM in one team: Gripped
• An embedded demand gen team, pre-seed to Series C: ToJupiter
• LinkedIn-led paid demand gen with published fees: Kiin
• Enterprise and global B2B programmes: Fox Agency, Ledger Bennett, Transmission
• Brand and creative-led B2B tech: Velocity Partners
• HubSpot and RevOps-led demand gen: Digital Litmus, Six & Flow

A London demand generation agency can mean four different businesses: a paid media team, an outsourced marketing department, an enterprise brand-to-demand network, or a HubSpot and RevOps consultancy. Most bad hires come from buying one when you needed another. The categories below separate them.

The scorecard: facts you can check

No opinion scores. Each column is something the agency states on its own site, as read on 30 October 2026.

"Results with numbers" counts named client results with a figure published on the agency's own site. "Not stated" means we could not find it on the site, not that it does not exist.

The agencies, by category

Best for an outsourced SaaS marketing team

Startups and scale-ups that need the whole marketing function, not one channel.

Rocket SaaS

10 York Road, London SE1 7ND, with an in-person London office. About 67 people named on its site; says it bootstrapped to £5.1M ARR in five years. B2B SaaS startups and scale-ups with limited in-house resource. LinkedIn, Meta and Google ads, SEO and AI search, content, lead magnets, CRO, "ABM Lite" on Clay, HubSpot. Published tiers: £5,000, £7,500, £10,000 and £15,000 a month; cancel anytime.

The broadest SaaS offer on this list and the most published results: Fonn 200+ leads in six months and £220K ARR; RAM Tracking +134 monthly demo or quote requests at £89.68 each; Startle CPL down 50% on Google Ads; Stora 40+ inbound SQLs a month.

Tradeoff: built as the outsourced team for under-resourced SaaS; a company with its own marketers that wants one specialist channel run deeply may be buying breadth it does not need.

Best for Series A to D SaaS wanting paid, SEO and ABM in one team

Companies past product-market fit with a sales team and a pipeline target.

Gripped

140-148 Borough High Street, London SE1. Founded 2017; 160+ SaaS, AI and tech companies helped. Exclusively B2B SaaS, AI and tech; states £2M to £20M ARR on its homepage (up to £50M in its FAQ) and no pre-seed or pre-product-market-fit. Demand gen, ABM, paid search, LinkedIn, SEO and GEO, web. Published: Advisory from £3,500 a month, Performance from £7,500, Scale from £15,000; says most clients invest £8K to £12K.

Gripped is explicit about who it is for and publishes pipeline results: Crownpeak £1.3m pipeline in one quarter from paid search and social, Nexstor £2m return from a £60K paid budget, Nozzle a run rate of 200 qualified leads.

Tradeoff: by its own terms not for pre-seed companies, teams without sales, or anyone needing pipeline inside 60 to 90 days.

Best for an embedded demand gen team, pre-seed to Series C

Founders who want senior operators inside their Slack rather than an account manager.

ToJupiter

Registered at 86-90 Paul Street, London EC2A (registered address; no separate office stated). Founded 2024; "seven senior operators". B2B SaaS from pre-seed to Series C; founders from MarTech and cybersecurity. Embedded demand gen £7,500 to £10,000 a month; embedded paid media £4,500 to £5,500 (ad spend under £50k a month); three-month minimum.

The embedded model means a demand gen lead works inside your team with weekly sales syncs. Published results: usecure $3.77M new pipeline from paid media, SearchPilot +37.2% meetings booked at £223 per lead, Reachdesk 120 demo requests from a new pricing page.

Tradeoff: small and young; an enterprise that wants a multi-office agency or a large brand and creative team should look at the enterprise category.

Best for LinkedIn-led paid demand gen with published fees

Sales-led B2B SaaS where paid media is the main demand engine and the fee should be known up front.

Kiin

Great Portland Street, London W1W. Founded 2019; team of 8, three ex-LinkedIn. 200+ B2B accounts run; B2B SaaS only. LinkedIn, Google Ads, Meta and Reddit in one funnel, reported as pipeline. Fees published: $2,500 a month LinkedIn only, $4,500 LinkedIn and Google, $5,500 (about £4,100) full paid media.

Kiin runs paid demand generation the way a sales-led SaaS company buys: LinkedIn creates demand on a named account list, Google captures it, Meta and Reddit keep the list warm, and one specialist owns the budget split and the pipeline report. Accounts are benchmarked against the Kiin Labs panel of $65M+ of LinkedIn spend.

Named results: Storysnap, $3M+ pipeline from LinkedIn Ads; Lumi AI, blended CPL from $455 to $176.

Tradeoff: we wrote this list, and we are paid media led. If you need SEO, content production, brand or HubSpot builds from the same team, pick a broader agency below.

Best for enterprise and global B2B programmes

Multi-region technology brands that need brand, ABM, media and creative under one roof.

Fox Agency

8 Devonshire Square, London EC2M; also Leeds, New York and Denver. "11 teams, 80 experts". States it is always global, always B2B, always tech: SaaS, fintech, IT and cloud, telco, electronics, Industry 4.0. Strategy, brand and creative, PR, media and performance, events. Pricing not published.

Fox combines PR and creative with performance media, which suits a tech brand launching across markets. Published results: DataStax 1159% more qualified leads and 77% lower CPL; intelliflo 3k MQLs over 18 months. Other named clients include Keysight and TE Connectivity.

Tradeoff: integrated brand, PR and performance; a lean company that only needs paid media run will pay for breadth.

Ledger Bennett

Havas Village, 3 Pancras Square, London N1C; also San Francisco and Chicago. Enterprise B2B demand generation and ABM, sales enablement, paid media, content syndication, programmatic, marketing automation (HubSpot, Marketo, Pardot, Eloqua) and staff augmentation. Pricing not published.

Ledger Bennett is built for account-based programmes at global brands, with 6sense-targeted LinkedIn and syndication. Published result: Trend Micro $22m (£19m) in pipeline with 4.3x account engagement. Named clients include GE Digital, GE Vernova, Canon, Acxiom and John Crane, and it supplies marketers on secondment through its Fluid Talent service.

Tradeoff: enterprise ABM for global names inside the Havas network; not set up for early-stage SaaS on small budgets.

Transmission

The Clove Building, 4 Maguire Street, London SE1; offices including Dallas, New York and Delhi. Founded 2013 (as Pulse); 250+ employees; acquired Earnest in 2025. Brand, GTM, ABX, paid media, creative, content syndication and its Intelligent Demand Engine; official LinkedIn, Meta, X and Xing partner. Pricing not published.

The largest B2B specialist network on this list. Published results: Cloudflare APJ 13.9 ROI across three quarters with a 74% pipeline uplift; Bricsys 1,598% more conversions from generative AI channels; Cashplus 10k sign-ups in under two months. Named clients include Microsoft, Snapdragon and Mastercard.

Tradeoff: enterprise scale and enterprise minimums; early-stage SaaS with a small budget is not what the work showcases.

Best for brand and creative-led B2B tech

Tech marketers who want the story fixed before the media is bought.

Velocity Partners

60 Great Portland Street, London W1W; also New York. B2B tech marketing strategy, creative, performance marketing (campaigns, analytics, SEO, marketing ops) and ABM. The site says it is becoming Pretzl, owned by Next15. Pricing not published.

Velocity made its name on B2B storytelling and still leads with strategy and creative, with performance and ABM behind it. Published result: Webhelp 175 new leads at 70% below budgeted cost, Google impressions up 109% in a month. Named clients include Demandbase, Calm Business and Geotab.

Check the Pretzl transition when you speak to them: the team and name are changing.

Tradeoff: brand-heavy by design; a team that wants a pure paid media execution partner may find it too strategy-led.

Best for HubSpot and RevOps-led demand gen

Companies whose bottleneck is the CRM, routing and nurture rather than ad spend.

Digital Litmus

86-90 Paul Street, London EC2A. Platinum HubSpot partner. RevOps programmes and managed RevOps, HubSpot consulting, migrations and websites, systematic ABM, AI consulting, for ambitious B2B businesses on HubSpot. Ballpark published: a small growth programme about £5k a month, a large one about £15k.

Digital Litmus treats demand gen as a systems problem: data, routing and ABM inside HubSpot. Published results: Spektrix £1.6M of closed business from ABM; RocheMartin 602% pipeline growth. It also rebuilt Cambridge Spark's HubSpot, and publishes its pricing ballpark, which few consultancies do.

Tradeoff: now positioned as a HubSpot and RevOps consultancy; not the pick if you mainly need LinkedIn or Google run day to day.

Six & Flow

Aviation House, 125 Kingsway, London WC2B; headquarters appears to be Manchester, also Dublin, Amsterdam and Toronto. HubSpot Elite partner for 10+ years. HubSpot implementation and AI CRM enablement, RevOps consulting, demand generation, sales enablement, data. Says it has driven growth for 500+ brands. Pricing not published.

Six & Flow is the larger HubSpot-first option, working across software, professional services, recruitment and manufacturing. Published results are CRM outcomes: The CFO Centre HubSpot adoption from 20% to 100% of regional directors; YunoJuno 92% data completeness.

Tradeoff: published results are CRM and operations outcomes, not paid media pipeline; buy it to fix the system, not to run ads.

How to choose

1. "Which of the four businesses are you?" Paid media team, outsourced marketing department, enterprise network, or HubSpot consultancy. Match it to your bottleneck.
2. "Show me a result with a pipeline number." Leads and impressions are not pipeline. Most agencies above publish at least one; ask for one in your segment.
3. "What is the fee, and what does it cover?" Four agencies on this list publish pricing. Media is extra everywhere.
4. "Who works on my account?" At an enterprise network a small budget gets a junior; at an embedded team you get the founder's time.
5. "What does a demo cost in my market?" Across 268 LinkedIn advertisers the median demo request costs $350, UK $364; anyone quoting far below that should explain how.

What demand gen actually costs on LinkedIn

From the Kiin Labs cost per demo report (268 advertisers, $8.25M of demo-request spend, 20,277 demo leads): the median demo lead costs $350, a quarter of accounts pay under $161 and a quarter over $754 on the same monthly budget, and UK demo requests run $364 against $520 in the US. The same advertiser pays 57% less per demo lead in the inbox (Conversation and Message Ads) than in the feed.