OpenServed

Best Lead Generation Agencies in London, United Kingdom (2026) – Ranked by Case Studies

SoproVisit Website →
Wooshii Client-verified
Lead Generation, Email Marketing
Media & Broadcasting
51-200 Employees
N/A
London, United Kingdom
N/A
  • 1,813 high-quality leads generated
  • £200,000+ in revenue and 70% ROI, outperforming all other channels
On Device Research Client-verified
Lead Generation, Email Marketing
Professional Services
51-200 Employees
N/A
London, United Kingdom
N/A
  • Averaged 34 monthly leads
  • Leads across the UK, Singapore and Australia
Insureflow Client-verified
Lead Generation, Email Marketing
Insurance
11-50 Employees
N/A
London, United Kingdom
N/A
  • 100+ leads in under three months
  • Near 3% success rate from a data set of ~6,000 contacts
New Perspective MarketingVisit Website →
Carbon Clean Client-verified
Branding, SEO, Lead Generation
Environmental Services
51-200 Employees
N/A
London, United Kingdom
N/A
  • $113M+ pipeline value created in the first year from online sources
  • +400% organic traffic over 6 months
  • +162% lead generation YoY
  • Millions added to pipeline within 60 days
Whiteoaks InternationalVisit Website →
Glasswall Client-verified
Content Marketing, Lead Generation
Cyber Security
51-200 Employees
N/A
London, United Kingdom
N/A
  • 124+ pieces of coverage
  • 48+ national and broadcast media interviews, leading to 30 pieces of coverage
  • Marketing assets downloaded 70 times
Acceleration PartnersVisit Website →
DAZN
Lead Generation
Media & Broadcasting
1K-5K Employees
N/A
London, United Kingdom
N/A
  • 124+ new publishers recruited in three months
  • 78% publisher activation rate
  • 7.2x ROI
  • 492,648 clicks generated
  • 68% share of affiliate conversions delivered by AP
Le Col (Cost-Effective Growth)
Lead Generation
Cycling
N/A
N/A
London, United Kingdom
N/A
  • +85% revenue QoQ
  • -41% average cost of sale
  • +64% new customer sales QoQ
Le Col (Global Partnership)
Lead Generation
Cycling
N/A
N/A
London, United Kingdom
N/A
  • +282% affiliate revenue share over six years (5.8% to 22%)
  • +31% global, +146% US and +16% UK revenue YoY
  • +67% US and +51% UK new customer acquisition YoY
100 Pound SocialVisit Website →
Nimbulent
Lead Generation
Consulting
N/A
N/A
London, United Kingdom
N/A
  • 20,000 UK founders added as LinkedIn connections in 12 months
  • About 50 connection accepts per day, about 10 responses
  • Up to 5 sales meetings per day
ReMake
Lead Generation
SaaS
N/A
N/A
London, United Kingdom
N/A
  • LinkedIn connections grew from 1,000 to 6,000+
  • 5-10 solid contacts per month from responses
FitSprint
Lead Generation
SaaS
1-10 Employees
N/A
London, United Kingdom
N/A
  • 1 new subscription per day after the first month
Prime DigitalVisit Website →
London Steel Services
PPC, Lead Generation
Manufacturing
11-50 Employees
N/A
London, United Kingdom
N/A
  • -67% cost per lead (£89 to £29)
  • £49K revenue generated in the first two months
  • 70 leads delivered in seven weeks
  • 16x return on investment on under £3K ad spend
Reflect DigitalVisit Website →
Vizlib
PPC, Lead Generation
SaaS
51-200 Employees
N/A
London, United Kingdom
N/A
  • 229% increase in lead volume in three months
  • 90% improvement in lead-to-customer conversion cost
  • 73.3% rise in conversion rate
  • 52.9% YoY drop in CPA
SalesARVisit Website →
ZoomMedia
Lead Generation
Marketing
11-50 Employees
N/A
London, United Kingdom
N/A
  • 5,000 contacts researched
  • 11 appointments scheduled
  • 3% reply rate
AMW Media LTDVisit Website →
Black Steel Doors
PPC, Content Marketing, Lead Generation
Manufacturing
N/A
N/A
London, United Kingdom
N/A
  • £1.13m revenue won in the CRM, 112 deals (Apr-Aug 2026)
  • 328 appointments booked
  • £70.9 returned for every £1 spent
memoryBlueVisit Website →
Becrypt
Lead Generation
Cyber Security
N/A
N/A
London, United Kingdom
N/A
  • $190K monthly revenue run-rate
  • 14 active resellers recruited in 18 months
  • Major distributor signed within 6 weeks
  • First deal closed within 90 days
Circus PPC AgencyVisit Website →
CPD
PPC, Lead Generation
Education
11-50 Employees
N/A
London, United Kingdom
N/A
  • 412% lead volume increase
  • 84% CPL reduction
POLARISVisit Website →
Reachdesk
SEO, Lead Generation
SaaS
51-200 Employees
N/A
London, United Kingdom
N/A
  • 5x return on investment
  • 420% increase in leads
BelkinsVisit Website →
Token.io
Lead Generation
Fintech
51-200 Employees
N/A
London, United Kingdom
N/A
  • 50 appointments booked in 6 months
  • 30% qualified opportunities

Find the best Lead Generation agencies in your city

  • London, United Kingdom