DiggThe best B2B lead generation agencies in 2026 are Belkins, SalesRoads, CIENCE, Callbox, Cleverly, Martal Group, SalesHive, Leadium, Sopro, ColdIQ and Diggsolution. Large agencies like Belkins and SalesRoads usually charge $5,000 to $15,000 a month and suit mid-market and enterprise teams. Smaller specialists like Diggsolution suit startups, agencies and niche B2B companies that want the same outbound engine at a lower cost.
Picking a lead generation agency comes down to three questions. Do you need volume or precision? Do you want cold email, cold calling, or both? And how much can you spend each month before you see meetings?
We run outbound for B2B clients every day, so we know what these agencies do well and where they fall short. Below are the agencies that appear most often in buyer shortlists this year. To be transparent, Diggsolution is our own agency, and we've placed it last.
Quick comparison
| Agency | Best for | Main channels | Typical monthly cost |
|---|---|---|---|
| Belkins | Mid-market appointment setting | Email, LinkedIn, calling | $5K to $15K |
| SalesRoads | US-based cold calling | Calling, email | About $9.5K per 4 weeks |
| CIENCE | Enterprise SDR teams | Email, calling, LinkedIn, ads | Custom |
| Callbox | Multichannel ABM campaigns | Calling, email, LinkedIn, webinars | Custom |
| Cleverly | LinkedIn-led outbound | LinkedIn, email, calling | Custom |
| Martal Group | Tech and SaaS sales outsourcing | Email, calling, LinkedIn | Custom |
| SalesHive | US SDRs on monthly terms | Email, calling, LinkedIn | From $4.5K |
| Leadium | Growth-stage B2B outbound | Email, LinkedIn | Custom |
| Sopro | UK and EU prospecting | Custom | |
| ColdIQ | Clay and AI-powered outbound | Email, LinkedIn | Custom |
| Diggsolution | Startups, agencies and niche verticals on a budget | Email, calling, LinkedIn, SEO, AI search | Monthly retainer, free sample list first |
1. Belkins
Belkins has run outbound since 2017 across more than 50 industries. Cold email is its core, with calling and LinkedIn layered on top, and it has one of the strongest review profiles on Clutch. Best when you have a mid-market budget and want a large, proven team.
2. SalesRoads
A Florida-based calling specialist with dedicated SDRs, a strategist and coaching on every account. Unusually, it publishes its pricing and offers a satisfaction guarantee on its four week cycles. Best for US phone-first campaigns.
3. CIENCE
Built for scale, with managed SDR teams supported by its own data platform. Best for enterprises that need many reps running at once.
4. Callbox
Around twenty years in the market, combining calls, email, LinkedIn, live chat and webinars into account-based campaigns. Best for complex sales with several decision makers.
5. Cleverly
Leads with LinkedIn outreach, backed by cold email and calling. Best if your buyers are active on LinkedIn.
6. Martal Group
Outsourced sales development focused on technology companies. Best for SaaS and IT firms entering new markets.
7. SalesHive
US-based SDRs supported by its own AI platform, on month to month contracts. Best if you want flexibility without a long commitment.
8. Leadium
Full outbound for growth-stage companies. Best for teams with a proven offer that need more pipeline.
9. Sopro
Email prospecting with strong coverage of UK and European markets. Best for companies selling into Europe.
10. ColdIQ
A newer agency built on Clay and AI tooling for personalized outbound. Best for tech-savvy teams who want modern data workflows.
11. Diggsolution
Best for startups, agencies and niche B2B companies that want an enterprise-style outbound engine without an enterprise bill. We run cold email, cold calling and LinkedIn at the same time as SEO and AI search visibility, so outbound and inbound feed each other. We specialize in SaaS, marketing agencies, Amazon brands, real estate and healthcare. Every new client gets a free sample lead list before signing.
How to choose a lead generation agency
- Match the channel to your buyer. Executives at large firms rarely answer the phone; founders of small firms read their own email.
- Ask for a sample list or pilot before signing a long contract.
- Check independent reviews on Clutch and G2, not just case studies on the agency's own site.
- Ask who owns the data, inboxes and domains if you leave.
- Make sure reporting shows meetings and pipeline, not just emails sent.