Top 10 B2B Lead Generation Agencies in the USA: A 2025 Guide

Finding new customers sounds easy! Send a few emails, book a few calls, and close a deal, right? In reality, generating qualified leads takes strategy, timing, and precision. 

That’s where a b2b lead generation agency comes in. These agencies blend research, copywriting, and automation to make sure every outreach feels personal and lands in front of the right people. 

Behind the scenes, they rely on platforms like Manyreach to handle the heavy lifting, managing mailboxes, tracking deliverability, and scaling campaigns across teams. 

It’s this mix of human creativity and smart automation that turns outreach into predictable growth and conversations into customers.

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10 B2B Lead Generation Agencies in the USA

Finding the right B2B lead gen agencies was a little tricky, given so many of them are mushrooming around the corner now. That’s why we kept in mind a few things before creating the list:

• First we analyzed their growth in the market, how many meetings they booked for the clients, and positive outcomes.
• Next, we focused on how each agency tailor their emails for each client campaign. For this we went through their messaging around their client’s ideal customer profiling. 
• Then we focused on the technology and tools they used for deliverability, and how ethical they were in terms of ethical data sourcing.
• Finally, we read their client testimonials to find out deeply about their reputation. 

Here are the 10 lead gen agencies that serve in the USA. Learn more about them:

1. Belkins

Belkins is one of the most well-known b2b lead generation agencies in the USA. It helps B2B brands in SaaS, technology, and professional services generate qualified meetings through highly targeted outbound campaigns.

Why They Stand Out: Belkins stands out for its end-to-end approach, combining human-verified research, personalized messaging, and deliverability optimization. Its transparency and emphasis on measurable ROI make it one of the top choices for companies looking for predictable pipeline growth.

Key Features:

• Outbound Campaign Strategy: Belkins designs multi-channel campaigns by combining cold emails, LinkedIn, and nurturing sequences. This practice ensures continuous lead flow while maintaining a natural, and non-spammy tone.
• Prospect Research: The team manually verifies every contact, ensuring relevance and accuracy for each campaign. This helps clients avoid wasted outreach and low-quality data.
• Deliverability Management: Belkins warms up domains, manages sender reputation, and optimizes email infrastructure so every email has the best chance of landing in the inbox.
• CRM Integration: Their systems sync seamlessly with Salesforce, HubSpot, and Pipedrive. That's how they give clients real-time visibility and full-proof campaign results.
• Performance Tracking: This agency's detailed dashboards display open rates, replies, booked meetings, and ROI metrics for complete transparency.

Revenue: ~$57.2 Million

Company Size: 200+ Employees

Location: Dover, Delaware, USA

Pricing: Starts around $5,000/month; customized plans available.

2. Cleverly

Cleverly is a U.S.-based lead generation agency that merges automation and human expertise to drive consistent B2B appointments. It is known for its LinkedIn and cold email outreach, and serves thousands of SaaS, marketing, and consulting firms worldwide.

Why They Stand Out: Cleverly’s strength lies in its use of campaign data from thousands of past clients to inform every new outreach sequence. This data-backed approach helps brands achieve predictable engagement without compromising personalization.

Key Features:

• LinkedIn Lead Generation: Cleverly builds customized outreach campaigns on LinkedIn, and sends messages that sound authentic and spark conversations with ideal buyers.
• Cold Email Campaigns: Their team crafts high-converting email sequences that highlight each client’s unique value proposition, leading to more replies and meetings.
• Content Writing & SEO: Cleverly supports inbound marketing through optimized blog content to improve visibility and attract organic leads, beyond outreach.
• Performance Analytics: Every campaign includes detailed reports that measure open rates, replies, and ROI, helping clients refine their strategy.
• A/B Testing: Cleverly also continuously tests messaging, subject lines, and send times to improve response rates and campaign effectiveness.

Revenue: ~$5 Million

Company Size: 10–49 Employees

Location: Los Angeles, California, USA

Pricing: Begins at $1,000+/month, customized based on campaign complexity.

3. SalesHive

SalesHive is a performance-based b2b lead gen agency that helps B2B brands scale their outbound sales through remote SDR teams and automated outreach. The agency serves hundreds of U.S. companies, from startups to Fortune 500 firms.

Why They Stand Out: SalesHive’s scalable model combines human research with automation. Clients can deploy U.S.-based SDRs while leveraging AI-backed email systems for faster execution and better performance.

Key Features:

• Cold Calling: SalesHive hires and manages professional B2B cold callers who introduce your business to potential customers, explain your offerings, and secure meetings with decision-makers.
• Email Marketing: The agency runs targeted outbound campaigns through its proprietary email platform. This approach ensures engagement with qualified prospects while minimizing deliverability issues.
• Remote SDRs: SalesHive provides part-time and full-time remote Sales Development Representatives who prospect, qualify leads, and schedule meetings, helping companies grow without increasing overhead.
• Automation Integration: Their software integrates seamlessly with popular CRMs. And that helps them in making campaign tracking and follow-up easy.
• Reporting & Analytics: Clients gain access to live dashboards showing campaign performance, conversions, and pipeline value in real time.

Revenue: ~$148.8 Million

Company Size: 100+ Employees

Location: Colorado, USA

Pricing: Starting at $4,000/month; higher-tier packages available.

4. CIENCE

CIENCE is a global lead generation marketing agency that offers fully managed outbound and inbound services. This agency is also known for its combination of AI, machine learning, and human research teams.

Why They Stand Out: With one of the largest global SDR teams, CIENCE blends data-driven targeting and automation to execute thousands of campaigns simultaneously for enterprise clients.

Key Features:

• Account-Based Marketing: CIENCE builds highly personalized account strategies to reach decision-makers across multiple touchpoints. This method boosts engagement and response rates.
• Data Science Targeting: Their in-house algorithms analyze firmographic and intent data to identify companies most likely to buy.
• Omnichannel Outreach: CIENCE integrates email, phone, and social platforms into one cohesive system to maximize outreach effectiveness.
• CRM Integration: The agency makes sure smooth connectivity between outreach campaigns and client CRMs for transparent performance tracking.
• Performance Optimization: Dedicated analysts continuously monitor campaigns and refine them for higher conversions and improved ROI.

Revenue: ~$260.3 Million

Company Size: 1,000+ Employees

Location: Denver, Colorado, USA

Pricing: Custom pricing available upon consultation.

5. Martal Group

Martal Group is a top-rated b2b lead generation agency based in Toronto with a strong U.S. presence. It provides full-funnel lead generation and SDR outsourcing for SaaS, IT, and professional service firms.

Why They Stand Out: Martal Group employs senior, North American SDRs who act as part of your internal sales team. So they're famous for blending experience, technology, and a hands-on approach to outreach.

Key Features:

• Sales Development Outsourcing: Martal’s on-demand SDRs handle prospecting, outreach, and meeting scheduling to extend your internal sales capacity.
• Multi-Channel Prospecting: They reach decision-makers through email, LinkedIn, and phone to maximize engagement opportunities.
• Data Enrichment & Research: In Martal, every contact is validated using firmographic and intent-based data for high accuracy.
• CRM Syncing: Their systems integrate with Salesforce, HubSpot, and other CRMs for seamless tracking.
• Performance Transparency: Clients receive detailed progress reports showing pipeline growth and campaign ROI.

Revenue: ~$20 Million

Company Size: 200+ Employees

Location: Toronto, Canada / U.S. operations

Pricing: Starting at $5,000/month, depending on SDR involvement.

6. Pearl Lemon Leads

Pearl Lemon Leads is a U.K.-founded lead generation agency with a strong U.S. presence. It provides cold email, phone, and LinkedIn outreach for B2B companies across various industries.

Why They Stand Out: The agency’s strength lies in its custom-built campaigns that mirror each client’s tone of voice and goals. Pearl Lemon Leads merges data research with creative messaging to build trust early in the outreach process.

Key Features:

• Cold Email Campaigns: The agency runs segmented campaigns that connect brands with prospects aligned with their ICP, improving engagement and response quality.
• LinkedIn Prospecting: Their team executes targeted LinkedIn outreach to book meetings and strengthen brand visibility.
• Appointment Setting: Dedicated reps schedule meetings with qualified leads so internal teams can focus on closing deals.
• Campaign Optimization: Pearl Lemon Leads uses analytics to refine messaging and targeting, ensuring continuous performance improvement.
• Prospect Validation: They manually verify contact data, guaranteeing accuracy and reducing bounce rates.

Revenue: ~$3.5 Million

Company Size: 25–50 Employees

Location: London, UK, also serving U.S. market

Pricing: Custom pricing based on project scope.

7. Nerdy Joe

Nerdy Joe is a boutique b2b lead generation agency that promises results upfront. Their pay-for-performance model appeals to startups and growing companies seeking guaranteed meeting outcomes.

Why They Stand Out: Nerdy Joe differentiates itself with transparency and accountability. They charge clients only for qualified meetings booked — ensuring performance aligns directly with results.

Key Features:

• Cold Email Outreach: Every campaign includes hand-written email personalized for each recipient, increasing reply rates and rapport.
• Meeting Guarantee: Nerdy Joe promises booked appointments within the first campaign cycle or clients pay nothing.
• ICP Research: The agency identifies and profiles ideal buyers with precision, improving lead quality and conversion.
• A/B Testing: Subject lines, CTAs, and email tone are tested regularly for maximum performance.
• Reporting Dashboard: Clients gain insights into reply patterns, conversion trends, and ROI metrics.

Revenue: ~$3 Million

Company Size: 10–25 Employees

Location: Austin, Texas, USA

Pricing: Starts at $2,500/month.

8. GrowthRhino

GrowthRhino is a Canadian lead generation marketing agency. However, it supports entire North American startups including the USA’s with outbound growth and conversion strategy.

Why They Stand Out: They focus on startup acceleration, helping early-stage companies validate messaging, build systems, and scale outreach.

Key Features:

• Cold Email Strategy: GrowthRhino develops personalized campaigns aligned with buyer intent to maximize engagement.
• Data Research: Each lead is verified manually, reducing wasted outreach and improving conversion accuracy.
• CRM & Workflow Setup: They help teams integrate outreach workflows into existing systems for smoother operations.
• Performance Reviews: Weekly optimization calls ensure email alignment and audience targeting.
• Sales Enablement: Offers templates, scripts, and tools to train internal SDRs for long-term scalability.

Revenue: Private

Company Size: 10–50 Employees

Location: Toronto, Canada

Pricing: Custom quotes available.

9. frontBrick

frontBrick is a U.S.-based b2b lead gen agency. They specialize in appointment setting and data-driven prospecting for small to mid-sized businesses.

Why They Stand Out: The agency emphasizes clean data, personalization, and deliverability — ensuring each campaign converts more and bounces less.

Key Features:

• Prospect Research: frontBrick builds tailored lists using firmographic and intent-based criteria, ensuring high-quality contacts.
• Domain Setup: They handle custom domain warm-up and configuration to protect sender reputation.
• Email Sequencing: Every email is written to mirror the client’s voice while sounding natural and professional.
• Campaign Monitoring: Weekly performance reviews help clients track engagement and adjust strategy quickly.
• Follow-Up Support: Their team provides guidelines for client-side nurturing and lead management.

Revenue: Private

Company Size: 10–20 Employees

Location: United States

Pricing: Custom packages available upon request.

10. 310 Creative

310 Creative is a Los Angeles-based digital marketing agency lead generation firm. It offers both inbound and outbound growth programs for B2B companies.

Why They Stand Out: As a certified HubSpot partner, 310 Creative bridges the gap between marketing automation and sales enablement — making it a holistic growth partner.

Key Features:

• Inbound & Outbound Integration: They align cold outreach with inbound channels like SEO and content to drive consistent lead flow.
• HubSpot Enablement: 310 Creative helps businesses implement and optimize HubSpot CRM for pipeline tracking.
• Account-Based Marketing: They craft personalized ABM campaigns targeting enterprise-level buyers for high-value deals.
• Pipeline Analytics: Clients gain access to reports that map lead journeys from first touch to closed deal.
• Creative Campaign Development: Their team creates high-quality sales collateral, landing pages, and nurturing sequences.

Revenue: <$5 Million

Company Size: <25 Employees

Location: Los Angeles, California, USA

Pricing: Pricing available after consultation.

Selection Criteria

Before finalizing our list of the top 10 performers, we focused on a few important qualities that truly separate a great b2b lead generation agency from the rest. 

These include measurable results, smart use of technology, transparency, and the ability to scale outreach effectively. 

Here’s how we narrowed it down:

Performance & Proven Results

We gave priority to agencies that consistently deliver real outcomes, and not just vanity metrics. The ones that stood out were those driving qualified leads, setting high-value appointments, and converting opportunities into revenue.

To verify performance, we explored their case studies, analyzed client testimonials, and reviewed tangible metrics such as ROI growth, conversion ratios, and pipeline impact. 

Agencies with a solid track record across industries and a reputation for maintaining long-term partnerships rose to the top of our list.

Personalization & Technology

Next, we looked for agencies that blend human creativity with smart automation. The top-rated firms use advanced data segmentation, behavioral insights, and AI-backed optimization to personalize outreach at scale.

Their approach ensures every message feels relevant and timely; not robotic. 

These agencies improve engagement rates, by continuously testing and refining their strategies. So they build better prospect relationships, and help clients achieve sustainable growth in competitive markets.

Reputation & Client Feedback

Trust and credibility were key deciding factors. Each agency featured here practices transparency, maintains ethical communication, and provides honest, data-backed reporting.

These agencies also stay compliant with CAN-SPAM and GDPR regulations, to protect both client reputation and prospect trust. 

Positive testimonials, consistent client satisfaction, and long-term collaborations reinforced their standing as reliable partners.

Scalability & Strategy

Finally, we evaluated how well each agency can adapt, both to changing markets and evolving client goals. The best ones don’t just run campaigns; they build frameworks that grow with your business.

From testing pilot projects to fine-tuning large-scale operations, these agencies demonstrate agility, creativity, and a strategic mindset. 

So whether you’re a startup or an enterprise looking to scale globally, these firms have the structure and experience to deliver consistent, measurable growth.

How to Choose the Right B2B Lead Gen Agency

The right b2b lead generation agency should feel like an extension of your sales team. You first define your Ideal Customer Profile (ICP) — who you want to target, their challenges, and decision timelines. Then look for agencies that emphasize data quality and personalization rather than mass emailing.

Always ask about deliverability practices, domain reputation, and compliance with CAN-SPAM and GDPR laws. Transparent reporting is also key — ensure your partner provides clear metrics like open rates, replies, meetings booked, and conversions. Finally, begin with a short pilot campaign before scaling. The best agencies prove results fast and adapt quickly.

How Manyreach Can Help

Running outreach at scale is challenging. Manyreach helps agencies and internal teams simplify it all. You can connect unlimited mailboxes, monitor deliverability, and track real-time campaign performance under one dashboard.

Its automation capabilities make sending thousands of emails seamless while ensuring personalization and compliance. Whether you’re an established lead generation agency or just starting, Manyreach gives your team collaboration tools, analytics, and deliverability features that make outreach efficient and results-driven.

FAQs

Q1: What does a b2b lead generation agency do?

It helps businesses identify, engage, and convert potential customers into qualified leads through outbound and inbound strategies.

Q2: How much does B2B lead generation cost?

Prices for a B2B lead generation agency starts from $2,000 to $10,000 per month. It also depends on campaign scope and lead volume.

Q3: What industries benefit most from lead generation agencies?

B2B SaaS, tech, finance, and consulting firms gain the most value from specialized lead generation support.

Q4: Are lead generation agencies still effective in 2025?

Yes — especially those that use human research, automation, and deliverability optimization to ensure authenticity and scale.

Q5: Which agency is best for startups?

Nerdy Joe and GrowthRhino are ideal for startups needing agile, performance-based lead generation solutions.

Conclusion

A top-tier b2b lead generation agency can help you scale faster, connect smarter, and close better. Each of the ten agencies above brings its own strengths, from Belkins’ precision outreach to CIENCE’s enterprise automation and Nerdy Joe’s performance guarantees.

Whether you’re outsourcing your pipeline or building it in-house, success depends on personalization, persistence, and smart technology. And if you’re managing outreach internally, Manyreach gives your team the infrastructure to execute campaigns at scale, without losing control or deliverability.