Top 10 Cold Email Lead Generation Agencies: 2025 Guide

Cold outreach might sound simple, but turning a single email into a booked meeting needs strategy. So crafting emails that get noticed, and generate responses, need a combination of creativity, technology, and testing.

That’s why more businesses in 2025 are turning to cold email lead generation agencies. These specialists handle everything from identifying ideal prospects to writing persuasive copy and managing deliverability. 

Behind every successful agency, platforms like Manyreach provide the infrastructure for large-scale, compliant email operations. It connects multiple mailboxes, monitoring deliverability, and ensuring campaigns run seamlessly across teams.

Let’s explore the top 10 agencies shaping global cold email lead generation in 2025.

Top 10 Cold Email Lead Generation Agency

To compile this list, we evaluated agencies across performance, innovation, and reputation. Each company was assessed for:

• Proven campaign results and measurable ROI
• Personalization and data-driven targeting strategies
• Range of services across cold email, list building, and multichannel outreach
• Transparency and client satisfaction based on reviews and case studies

The following 10 agencies have demonstrated consistent excellence in building pipelines through compliant, personalized, and scalable cold email systems.

1. Belkins

Belkins is a USA-based global B2B appointment-setting and cold email lead generation agency. Known for helping companies secure 100–400 qualified meetings annually, Belkins delivers outreach programs that combine human insight with advanced automation.

Why They Stand Out: Belkins focuses on research-driven personalization—each campaign starts with detailed ICP mapping, ensuring every message resonates. Their proprietary tool, Folderly, enhances deliverability, helping clients achieve inbox rates above industry averages.

Key Services:

• Appointment Setting — Belkins offer end-to-end sales meeting booking, including prospect qualification, email outreach, and scheduling assistance, ensuring every meeting aligns with your target buyer profile.
• Lead Research — They also provide verified, human-sourced contact data from key decision-makers, using advanced enrichment and validation tools to maintain data accuracy and reduce bounce rates.
• Cold Email Campaigns — The agency designs personalized, multi-step email sequences that focus on relevance, clarity, and timing, supported by deliverability monitoring and performance-based optimization.
• Deliverability Optimization — They also manage domain warm-up, authentication, and reputation tracking through Folderly’s platform to maintain strong sender health and inbox placement over time.
• Campaign Reporting — Belkins also provide transparent analytics, tracking open, reply, and meeting rates to ensure continuous refinement and ROI measurement.

Revenue: Not Disclosed

Company Size: 200+ Employees

Location: Delaware, USA

Pricing: Custom proposal

2. Cleverly

Cleverly, based in California, is a cold emailing and LinkedIn lead generation agency serving startups and SMBs. They’re known for combining automation with handcrafted messaging that reflects each client’s voice and market.

Why They Stand Out: Cleverly blends AI-assisted targeting with human review to maintain personalization at scale. With over 3,000 campaigns executed, they use performance benchmarks to fine-tune every new engagement.

Key Services:

• LinkedIn Lead Generation — Cleverly handles highly personalized connection campaigns and follow-ups on LinkedIn, using conversational messaging and behavioral triggers to increase connection rates and build relationships organically.
• Cold Email Outreach — They handle everything from email creation and domain setup to ongoing optimization, ensuring emails reach inboxes, comply with regulations, and inspire real, high-quality responses.
  
  
• White-Label Services — The agency also provides outsourced cold email and LinkedIn campaigns for partner agencies, offering branded assets, reporting dashboards, and seamless client communication support.
• Content Strategy — They consistently develop SEO-optimized blogs, nurture sequences, and brand messaging frameworks that reinforce outreach efforts and boost thought leadership visibility for sustained inbound growth.
• Performance Reporting — Cleverly offers transparent analytics on campaign results that allows clients to make informed decisions.

Revenue: < $5 Million

Company Size: 10–25 Employees

Location: Los Angeles, USA

Pricing: Custom

3. frontBrick

frontBrick is a global cold email lead generation agency focusing on B2B SaaS companies. Their mission is to build scalable outbound systems that drive high-intent conversations and consistent pipeline growth.

Why They Stand Out: They specialize in technical deliverability, automation, and AI-based testing, ensuring each email lands in the inbox and speaks directly to a prospect’s needs. Their campaigns are especially effective for SaaS firms targeting global markets.

Key Services:

• Cold Email Lead Generation — frontBrick builds and manages AI-powered email sequences with smart audience matching, copy testing, and intent-based personalization to maximize engagement and conversions.
• Deliverability Setup — They handle complete technical setup, including DNS configuration, domain rotation, and warm-up systems to ensure long-term inbox health and consistent deliverability performance.
• Outbound SDR Support — The agency also provides dedicated remote sales teams to manage daily outreach, qualify prospects, nurture leads, and book meetings directly into your CRM or sales calendar.
• Campaign Analytics — They offer real-time performance metrics with A/B testing dashboards, helping clients measure open, reply, and conversion rates while continually optimizing future campaigns.
• Funnel Optimization — The agency integrates outbound insights with sales workflows to streamline handoffs and boost conversion efficiency.

Revenue: Not Disclosed

Company Size: 25–50 Employees

Location: Global (HQ in Europe)

Pricing: Starting around $2,500/month

4. Growth Rhino

Based in Canada, Growth Rhino is a B2B SaaS cold email and outbound growth agency. Their team helps startups and scale-ups validate ICPs, build outreach systems, and generate sales-qualified leads through precision targeting.

Why They Stand Out: Growth Rhino operates at the intersection of sales and marketing. They don’t just run campaigns—they help SaaS firms refine messaging, measure response quality, and scale successful playbooks across markets.

Key Services:

• Cold Email Campaigns — Growth Rhino crafts SaaS-specific, multi-step cold email sequences optimized for conversions, including A/B testing, behavioral triggers, and copy personalization to connect effectively with high-intent prospects.
• Growth Strategy — They design data-backed growth strategies that include detailed market testing, competitor benchmarking, and audience segmentation to identify untapped opportunities and scale campaigns efficiently.
• Outbound SDR Support — The agency provides experienced SDR teams dedicated to managing high-volume outreach, nurturing responses, and scheduling qualified demos or sales calls that directly support revenue targets.
• Pipeline Consulting — They offer full audits and optimization plans for outbound systems, refining messaging, cadence, and workflow automation to improve conversion rates and streamline sales handoffs.
• Campaign Analytics — Growth Rhino delivers in-depth reports on performance metrics like open, reply, and meeting rates, that helps clients make decisions based on real-time insights.

Revenue: < $5 Million

Company Size: 10–50 Employees

Location: Toronto, Canada

Pricing: Custom

5. Pearl Lemon Leads

Pearl Lemon Leads is a UK-based lead generation agency with a strong presence in Europe and the U.S. They offer tailored B2B outreach across cold email, LinkedIn, and telemarketing—serving industries from SaaS to professional services.

Why They Stand Out: Their team emphasizes list building and personalization. Every campaign begins with in-depth prospect research, ensuring accuracy and relevance before the first email is sent.

Key Services:

• Cold Email Outreach — Pearl Lemon Leads Executes multi-step, highly personalized email sequences designed to engage decision-makers, nurture relationships, and generate qualified responses through consistent testing and optimization.
• List Building Services — They develop verified, custom-built prospect lists tailored to specific buyer roles and industries, ensuring data accuracy, compliance, and a strong fit for your ideal customer profile.
• Appointment Setting — The agency manages the entire process of booking high-quality meetings with verified prospects, handling confirmations, calendar coordination, and pre-call preparation to maximize sales opportunities.
• LinkedIn Campaigns — They run relationship-based prospect engagement campaigns on LinkedIn, combining personalized messaging, profile optimization, and content interaction to build trust and spark meaningful business conversations.
• Multi-Channel Strategy — Pearl Lemon Leads integrates cold email and LinkedIn outreach with supportive follow-ups, ensuring consistent visibility and higher conversion rates across touchpoints.

Revenue: < £5 Million
Company Size: 25–40 Employees
Location: London, UK
Pricing: Packages start around £997/month

6. Martal Group

Martal Group is a North American B2B lead generation agency specializing in outbound prospecting, appointment setting, and cold email outreach for technology firms.

Why They Stand Out: Their hybrid team composed of onshore and nearshore SDRs, gives clients around-the-clock coverage. They integrate intent data to reach prospects already in the buying cycle, improving conversion rates and pipeline efficiency.

Key Services:

• Lead Generation & SDR Services — Martal offers fractional or full-service SDR teams that manage the complete outbound cycle, from prospecting and engagement to booking qualified meetings and passing leads directly to sales.
• Cold Email Outreach — They design highly personalized and compliant cold email campaigns that incorporate data enrichment, automated follow-ups, and A/B testing to maximize open and response rates across multiple buyer segments.
• Intent-Based Targeting — The agency utilizes behavioral and firmographic data signals to identify ready-to-buy leads, allowing clients to engage prospects at the optimal moment in their purchasing journey.
• Sales Enablement Consulting — They also provide consulting to optimize messaging, cadence, and follow-up workflows while ensuring alignment between marketing and sales teams for consistent revenue performance.
• Campaign Analytics & Reporting — Martal delivers transparent campaign dashboards and periodic insights that track engagement metrics, meeting rates, and pipeline contribution to demonstrate tangible ROI.

Revenue: Not Disclosed

Company Size: 100+ Employees

Location: Toronto, Canada & Austin, USA

Pricing: Custom

7. Growth.cx

Growth.cx is a global B2B SaaS-focused growth and cold email agency. They partner with early-stage SaaS companies to create scalable go-to-market systems that combine email, social, and data analytics.

Why They Stand Out: Unlike traditional agencies, Growth.cx embeds within clients’ teams as an outsourced marketing department. They balance creative experimentation with data-driven precision to accelerate product-led growth.

Key Services:

• Cold Email Lead Generation — Growth.cx creates end-to-end outbound email programs, from audience segmentation and copywriting to technical setup and campaign execution.
• Growth Marketing Strategy — The agency delivers performance-based marketing strategies designed to accelerate SaaS adoption and revenue growth.
• ICP & Message Development — Growth.cx conducts deep-dive Ideal Customer Profile research to define high-value buyer personas and market segments.
• Full-Funnel Management — Beyond generating leads, Growth.cx supports the entire buyer journey—from lead capture to qualification and handoff to sales.
• Analytics & Continuous Optimization — Each engagement includes detailed performance tracking and bi-weekly reporting.

Revenue: Not Disclosed

Company Size: 50–100 Employees

Location: Global (HQ in India)

Pricing: Custom

8. SalesHive

SalesHive is a USA-based outbound sales agency providing cold email, calling, and SDR services to B2B companies across industries. They combine human research with automation for scalable pipeline generation.

Why They Stand Out: SalesHive’s hybrid approach merges AI automation with human oversight. Their team guarantees consistent results through transparent reporting and a focus on measurable engagement metrics.

Key Services:

• Cold Email Campaigns — SalesHive designs fully managed outbound email systems that include email sequencing, follow-up logic, and audience segmentation.
• Remote SDR Teams — The agency provides dedicated U.S.-based and offshore SDR teams trained in outbound prospecting, lead nurturing, and appointment setting.
• Deliverability Optimization — SalesHive manages the technical foundation of every cold email campaign. This includes domain setup, SPF/DKIM authentication, inbox rotation, reputation monitoring, and continuous warm-up.
• Performance Analytics & Reporting — Every campaign comes with access to SalesHive’s analytics dashboard, where clients can monitor key performance indicators in real time, such as open rates, reply rates, meeting conversions, and ROI.
• Campaign Testing & Refinement — SalesHive also runs ongoing A/B testing across subject lines, templates, and cadence strategies. This data-led optimization ensures continuous performance improvement and scalability for long-term outbound growth.

Revenue: $34 Million

Company Size: 100+ Employees

Location: Colorado, USA

Pricing: Custom

9. Key Outreach

Key Outreach is a USA-based cold email and outbound prospecting agency specializing in helping B2B service providers build predictable lead pipelines.

Why They Stand Out: Their focus on structured outreach processes—backed by data enrichment and lead scoring, makes sure every campaign targets decision-makers who are genuinely likely to engage.

Key Services:

• Cold Email Outreach — Key Outreach develops tailored, multi-step cold email sequences designed specifically for service-based businesses. They use behavioral triggers, time-zone optimization, and custom copywriting to create natural, value-driven emails that earn replies instead of spam flags.
• Lead Qualification & Nurturing — They enable each contact to fit, intent, and be relevant. Their qualification process filters out unqualified prospects and identifies decision-makers who align with your ICP.
• List Building & Prospect Research — The agency combines manual research with trusted data enrichment tools to build clean, verified prospect databases.
• Appointment Setting — Key Outreach goes beyond generating interest, they schedule meetings directly between your sales team and qualified prospects.
• Performance Tracking & Optimization — Detailed analytics dashboards provide insight into open rates, response quality, and booked meetings.

Revenue: Not Disclosed

Company Size: 25–50 Employees

Location: New York, USA

Pricing: Custom

10. Letstrike

Letstrike is a U.S.-based cold email agency that helps B2B services and SaaS companies generate qualified meetings through data-driven outreach.

Why They Stand Out:

They emphasize campaign transparency, deliverability management, and consistent lead handoff. Each engagement is tailored to the client’s buyer persona and market maturity level.

Key Services:

• Cold Email Campaigns — Letstrike designs multi-step, conversion-oriented email sequences that mimic natural human conversation. 
• Prospect Research & List Building — The agency conducts in-depth Ideal Customer Profile mapping, combining firmographic, technographic, and intent data to curate precise prospect lists.
• Outreach Automation & Workflow Setup — Letstrike sets up scalable automation systems using best-in-class tools. That allows clients to manage outreach across multiple inboxes.
• Meeting Booking & Sales Handoff — The agency also focuses on booking meetings that convert. The team qualifies prospects, nurtures interest, and hands off ready-to-convert appointments directly to clients’ sales calendars, complete with meeting notes and contact insights.
• Performance Reporting & Analytics — They track campaigns in real time, with detailed reporting on deliverability, open rates, click-throughs, and meeting outcomes.

Revenue: Not Disclosed

Company Size: < 25 Employees

Location: USA

Pricing: Custom

Selection Criteria Breakdown

While picking the top 10 cold email lead gen agencies, we kept a few things in mind. These factors include personalization, performance, reputation, strategy and more. 

Take a look and learn more about it:

Performance & Proven Results

Each agency in this list demonstrates measurable performance—booked meetings, qualified leads, and tangible ROI. Verified case studies show sustained growth for clients across SaaS, tech, and B2B services.

Personalization & Technology

Top agencies use a mix of data enrichment, AI-driven testing, and behavioral segmentation. They personalize every message and manage the technical side of deliverability to achieve high open and reply rates.

Reputation & Client Feedback

All agencies maintain transparent communication and compliance with GDPR and CAN-SPAM regulations. Client testimonials consistently highlight responsiveness, reporting, and tangible results.

Scalability & Strategy

These agencies excel at designing small pilot campaigns, measuring outcomes, and scaling successful frameworks across markets—ensuring long-term growth through iteration and learning.

How to Choose the Right Cold Email Lead Gen Agency

To select the right cold email lead gen agency you have to keep a few things in mind. Those are: 

Understand Your ICP: The best results start with clarity. A strong agency will help you define your Ideal Customer Profile—covering industry, job title, company size, and pain points—before sending a single email.

Prioritize Deliverability: Deliverability is the backbone of cold email success. Choose agencies that offer domain warmup, spam prevention, and authentication setups like SPF, DKIM, DMARC to keep your sender reputation strong.

Demand Transparent Reporting: Partner with firms that share open metrics—like open rates, reply rates, meetings booked, and pipeline value—rather than vanity numbers. Transparency ensures accountability and measurable ROI.

Start with a small pilot project to assess alignment, performance, and communication before committing long term.

How Manyreach Can Help

Cold email agencies and in-house teams alike depend on reliable outreach infrastructure. That’s where Manyreach stands out, providing the technology backbone for scalable, compliant, and data-driven cold email systems.

With Manyreach, you can:

• Connect unlimited mailboxes and workspaces to manage campaigns at scale.
• Monitor deliverability and sender reputation using automated warm-up and smart-sending logic.
• Collaborate across teams with shared dashboards and analytics for replies, opens, and conversions.

Whether you manage outreach internally or partner with an agency, Manyreach ensures your cold email efforts remain efficient, compliant, and results-driven.

FAQs

1. Are cold email campaigns legal globally?

Yes, provided they comply with data privacy and anti-spam laws like CAN-SPAM (USA), GDPR (Europe), and PECR (UK). Always include an opt-out link and avoid misleading subject lines.

2. Which cold email agency is best for SaaS companies?

frontBrick, Growth Rhino, and Growth.cx specialize in SaaS-focused outreach, making them ideal for tech startups and software providers.

3. How much do cold email lead generation agencies charge?

Pricing varies by scope and region, typically ranging from $1,000 to $10,000 per month. It also depends on list size, market, and campaign complexity.

4. What makes a great cold email campaign?

Success depends on precise targeting, personalized messaging, good deliverability practices, and continuous testing of subject lines, timing, and value propositions.

5. Can I manage cold outreach internally?

Yes, you can manage with the right infrastructure. Platforms like Manyreach allow teams to handle multi-mailbox cold email operations effectively, ensuring deliverability and scale.

Conclusion

Cold email remains one of the most cost-effective and scalable B2B growth channels in 2025, but only when executed with precision. The agencies in this list have proven expertise in crafting campaigns that convert through personalization, compliance, and strong deliverability.

Whether you choose to partner with a specialized cold email lead generation agency like Belkins, SalesHive, or Pearl Lemon Leads, or build your own internal outreach engine; results depend on strategy and consistency.

If you’re ready to scale outreach without sacrificing control, explore Manyreach, the platform trusted by agencies and marketing teams to power compliant, data-driven email systems that turn cold prospects into real opportunities.