You’re paying an agency for meetings, but you’re actually paying them for their infrastructure. The difference between a cold email campaign that books calls and one that burns your domain comes down to what’s happening behind the scenes: inbox placement rates, ISP filtering rules, seed list testing, DNS authentication, and sending reputation management.
Most B2B companies don’t have the in-house expertise to manage dedicated sending domains, monitor blacklist status, configure SPF/DKIM/DMARC properly, or run the kind of gradual volume ramp-up that keeps mailbox providers from flagging them as spam. That’s what these agencies actually sell: the infrastructure and deliverability knowledge that makes outreach viable at scale.
The agencies on this list handle the full scope of cold email execution:
- Domain and IP warmup
- Inbox placement optimization
- List building with verification and hygiene
- Copywriting, campaign management, and often reply handling.
Some focus purely on email, while others layer in phone and LinkedIn for omnichannel coverage. The right choice depends on your sales cycle, budget, and how involved you want to be in the process.
We evaluated these agencies based on deliverability practices, including their approach to sender reputation monitoring, ISP-specific filtering, and seed list testing, along with service scope, client feedback, transparency, and track record in B2B outreach.
1. OutreachBloom
OutreachBloom is a done-for-you cold email agency built for B2B companies that want meetings booked without managing infrastructure, hiring SDRs, or touching the outreach process at all.
What services does OutreachBloom provide?
- OutreachBloom manages the entire cold email pipeline: dedicated domain provisioning, DNS authentication (SPF, DKIM, DMARC), email warmup, ICP definition, real-time list building, personalized copywriting, campaign execution, and reply management.
- OutreachBloom’s process begins with a kickoff call where their team defines your ideal customer profile and builds prospect lists in real time using premium B2B data sources. They provision fresh sending domains, configure all authentication records, and warm those domains before sending a single outreach email. Once campaigns launch, OutreachBloom handles replies, filtering positive responses and routing qualified conversations directly to your sales team.
- The model is designed for companies that want zero involvement in outreach mechanics. There are no SDRs to manage, no tools to learn, and no sending infrastructure to maintain. You focus on closing deals; they fill the top of the funnel.
What makes OutreachBloom different from other agencies?
- OutreachBloom focuses exclusively on cold email rather than spreading across multiple channels. This specialization means tighter deliverability management, faster setup, and a streamlined engagement without the complexity of coordinating phone, LinkedIn, and email simultaneously.
- While many agencies bundle email with calling and social selling, OutreachBloom’s entire operation is built around making cold email work at a high level. That means their deliverability practices (domain rotation, warmup protocols, authentication, and sending volume management) are core competencies rather than add-on services. In fact, many top-tier agencies use automated tools like Warmy.io to ensure their client domains stay out of spam folders
- For B2B SaaS companies, agencies, consultants, and professional services firms, this email-focused approach typically delivers faster time-to-first-meeting and lower cost-per-lead than omnichannel alternatives. The tradeoff is that companies needing phone or LinkedIn outreach will need a separate provider for those channels.
Primary Channel | Cold email (100% focus) |
Service Model | Fully done-for-you |
Domain & Warmup | Included (setup + ongoing) |
Deliverability Method | |
Reply Management | Included by default |
Phone / LinkedIn | Not offered |
Ideal For | B2B SaaS, agencies, professional services |
2. CIENCE
CIENCE is a B2B lead generation company that pairs managed SDR services with a proprietary AI platform (graph8) for multi-channel outbound at enterprise scale.
What services does CIENCE provide?
- CIENCE runs multi-channel campaigns spanning email, phone, chat, SMS, and digital ads. Their offering blends human SDR teams with AI-driven prospecting, data enrichment, visitor identification, and CRM integration through their graph8 platform.
- Founded in 2015 and headquartered in Denver, CIENCE has evolved from a pure SDR outsourcing shop into a hybrid services-and-software provider. Their model starts with a go-to-market system design phase, followed by managed outbound and inbound SDR teams executing campaigns across multiple channels simultaneously. The graph8 platform handles data, sequencing, visitor identification, and AI-powered conversations.
- CIENCE has served over 2,500 customers across 200+ industries and has appeared on both the Inc. 5000 and Financial Times Americas’ Fastest Growing Companies lists. Their pricing structure includes a one-time GTM system setup fee of $5,000 (or $2,500 for startups) plus ongoing fees that combine a performance component, a monthly platform license, and SDR team retainer costs.
When should you choose CIENCE over an email-only agency?
- CIENCE is a fit when you need enterprise-level outbound infrastructure with AI-powered prospecting, multi-channel orchestration, and deep CRM integration; not just email execution.
- The strength of CIENCE is scale and technology. If you need to run coordinated campaigns across email, phone, chat, and ads with proprietary data tools powering the targeting, their platform-plus-services model delivers that.
- The tradeoff is cost and complexity. The upfront investment and monthly fees make CIENCE more suitable for mid-market and enterprise organizations than early-stage companies or those looking for simple email-only outreach.
Primary Channels | Email, phone, chat, SMS, ads |
Service Model | SDR-as-a-Service + AI platform |
Setup Fee | $5,000 one-time ($2,500 for startups) |
Technology | Proprietary graph8 AI platform |
Customers Served | 2,500+ across 200+ industries |
Ideal For | Mid-market/enterprise B2B needing multi-channel at scale |
3. Belkins
Belkins is an omnichannel B2B appointment setting agency combining cold email, phone outreach, and LinkedIn prospecting with strategic consulting and CRM services.
What services does Belkins provide?
- Belkins offers appointment setting, cold email outreach, cold calling, LinkedIn lead generation, account-based marketing (ABM), deliverability consulting, HubSpot CRM consultancy, and paid advertising, making them one of the most comprehensive providers in the space.
- Founded in 2017, Belkins has grown into one of the most recognized names in B2B lead generation. They report having scheduled over 200,000 appointments for nearly 1,000 clients across 50+ industries, with a claimed 95% client retention rate and an average of $10 return on every $1 invested. Their client roster includes enterprise names like General Electric, Nvidia, Zendesk, and Cloudflare.
- Belkins takes a research-intensive approach. Their team hand-verifies leads against buyer personas, crafts email sequences tested across thousands of campaign variations, and launches campaigns within approximately 14 days. Typical results appear within 30-90 days. They also provide deliverability consulting and HubSpot CRM integration as supplementary services.
What does Belkins cost?
Belkins doesn’t publish transparent pricing, but third-party sources consistently report a range of $5,000-$15,000 per month depending on scope and service tier.
Not ready for a $5,000/month agency? You can manage your own deliverability and scale your outreach for a fraction of the cost. Try Warmy.io for free.
Belkins positions itself as a premium service, which means higher monthly investment than email-only agencies. The omnichannel approach (coordinating email, phone, LinkedIn, and potentially paid ads) requires more infrastructure and personnel, which drives the cost. Companies with smaller budgets or those needing only email outreach may find better value with focused providers.
Primary Channels | Email, phone, LinkedIn, paid ads |
Service Model | Full-service appointment setting |
Pricing Range | $5,000-$15,000/month (reported) |
Appointments Booked | 200,000+ for ~1,000 clients |
Additional Services | Deliverability consulting, HubSpot CRM, ABM |
Ideal For | Mid-market/enterprise B2B with complex sales cycles |
4. Martal Group
Martal Group is a global B2B lead generation and sales agency with an international team of experienced sales executives covering North America, the EU, and Latin America.
What services does Martal Group provide?
- Martal Group provides outsourced SDR teams, outbound and inbound lead generation, appointment setting, cold calling, LinkedIn outreach, email marketing, and account management across 50+ verticals, with a particular focus on tech and SaaS companies.
- Founded in 2009 and headquartered in Oakville, Ontario (with operations in San Francisco), Martal Group has over a decade of experience serving B2B companies from startups to Fortune 500 organizations. Their team of onshore sales executives across multiple geographies makes them particularly suitable for companies targeting international markets.
- Martal Group leverages real-time intent data and technographic signals to identify prospects actively evaluating solutions in your space. Their workflow includes building verified weekly prospect lists, validating contact details, executing personalized multi-channel outreach, and qualifying leads before passing them to your sales team. They’ve been recognized on the Financial Times Americas’ Fastest-Growing Companies list and the Everest Group’s B2B Sales Services PEAK Matrix Assessment.
What is Martal Group’s contract structure?
Martal Group requires a 3-month pilot program to establish campaign baselines and optimize targeting before transitioning to month-to-month billing.
The pilot period allows Martal’s team to test messaging, refine your ICP, and build a data-backed outreach strategy. After the initial commitment, month-to-month billing provides flexibility. This structure works well for companies willing to invest in an optimization phase but may not suit teams looking for immediate month-to-month flexibility from day one.
Primary Channels | Email, LinkedIn, cold calling |
Service Model | Outsourced SDR teams + account management |
Contract Structure | 3-month pilot, then month-to-month |
Geographic Coverage | North America, EU, Latin America |
Industries | 50+ verticals (focus on tech/SaaS) |
Ideal For | Tech companies needing international outreach |
5. Cleverly
Cleverly is a LinkedIn-first lead generation agency that also offers cold email as a complementary outreach channel, providing a systematic approach to prospecting across both platforms.
What services does Cleverly provide?
- Cleverly offers LinkedIn lead generation, cold email outreach, A/B testing, campaign optimization, white-label services for agencies, and pay-per-lead pricing options. Their cold email infrastructure uses dedicated Outlook accounts with US-based IPs.
- Cleverly built its reputation primarily on LinkedIn outreach and has since expanded into cold email. Their approach uses performance data from thousands of B2B campaigns to craft and optimize personalized messages at scale. For cold email specifically, they set up sending infrastructure with enterprise Azure accounts, multi-provider email verification, and dedicated US IP addresses for deliverability.
- Where Cleverly differs from the other agencies on this list is their emphasis on systematic, scalable outreach rather than deeply customized campaigns. They build lists based on target criteria, write sequences, test variations, and optimize based on response data. They also offer pay-per-lead pricing, which provides more predictable cost structures for some organizations.
When is Cleverly the right choice?
Cleverly works best when your target prospects are active on LinkedIn and you want a combined LinkedIn-plus-email strategy without managing campaigns yourself.
If LinkedIn is where your buyers spend time, Cleverly’s dual-channel approach can generate touchpoints across both platforms. The tradeoff is that their outreach leans more systematically than bespoke. Companies needing highly researched, one-to-one personalization may prefer a more boutique provider. Cleverly also does not offer phone outreach, so teams needing calling as part of their mix will need to look elsewhere.
Primary Channel | LinkedIn (email as complement) |
Service Model | Managed outreach + white-label option |
Pricing Model | Pay-per-lead option available |
Cold Calling | Not offered |
Personalization Level | Systematic and data-driven |
Ideal For | Companies targeting LinkedIn-active prospects |
How do these 5 agencies compare?
Agency | Focus | Phone | Pricing | Best For | |
OutreachBloom | Email only | ❌ | ❌ | Contact | DFY email, SaaS, agencies |
CIENCE | Multi-channel + AI | ✅ | ✅ | $5K setup + monthly | Enterprise, AI-powered scale |
Belkins | Omnichannel | ✅ | ✅ | $5K-$15K/mo | Enterprise appointment setting |
Martal Group | Multi-channel | ✅ | ✅ | Contact | Global tech, international SDRs |
Cleverly | LinkedIn + email | ❌ | ✅ (primary) | Pay-per-lead option | LinkedIn-active prospects |
How should you choose a cold email agency?
Start with your primary channel needs: email-only, email plus LinkedIn, or full omnichannel. Then evaluate deliverability practices, contract flexibility, pricing transparency, and whether the agency’s service model (DFY vs. SDR-as-a-Service) matches your team’s capacity.
If email alone drives your pipeline: OutreachBloom provides focused, 100% done-for-you execution with built-in deliverability management and reply handling.
If you need enterprise multi-channel infrastructure: CIENCE delivers AI-powered outbound across email, phone, chat, SMS, and ads with proprietary data tools.
If you want an omnichannel appointment setting with strategic consulting: Belkins combines email, phone, and LinkedIn with CRM consultancy and deliverability services.
If you’re targeting international markets: Martal Group offers onshore SDR teams across North America, Europe, and Latin America with intent-data-driven prospecting.
If your buyers are active on LinkedIn: Cleverly combines LinkedIn outreach with cold email and offers pay-per-lead pricing for predictable costs.
Why does email deliverability matter when choosing an agency?
Deliverability is the foundation of every cold email campaign. If your agency’s emails land in spam instead of the inbox, nothing else matters. Before signing with any cold email agency, confirm they follow these deliverability practices:
- They should use separate domains for outreach (never your primary domain)
- They must configure SPF, DKIM, and DMARC authentication on every sending domain
- They should conduct proper warming up of domains for at least 2 weeks before launching campaigns
- They must maintain reasonable daily sending volumes and monitor inbox placement rates continuously.
If the agencies you are talking with don’t mention email deliverability or warming up, this can be considered a red flag. Agencies that cut corners on deliverability will damage the sending infrastructure and produce poor results. The best agencies treat deliverability as a core competency, not an afterthought.
Maximize your cold email outreach with a solid email deliverability solution
Whether you’re working with an agency or managing cold email in-house, deliverability is what determines whether your outreach actually reaches decision-makers or gets filtered into spam folders.
Warmy.io is an email warmup and deliverability platform built to set up cold email outreach campaigns for success.
Warmy automates the technical work that keeps your emails landing in the inbox: gradual volume ramp-up, engagement simulation with real mailboxes, continuous inbox placement monitoring, and sender reputation management across major ISPs.
Here’s what Warmy handles:
Automated email warmup: Warmy gradually increases your sending volume while simulating natural email engagement patterns, building positive sender reputation before you launch campaigns.
Continuous monitoring: Real-time inbox placement testing across Gmail, Outlook, Yahoo, and other providers shows you exactly where your emails are landing and alerts you to deliverability issues before they tank your campaigns.
Deliverability tools: Built-in SPF, DKIM, and DMARC validation, blacklist monitoring, and email template testing help you identify and fix issues that trigger spam filters.
Scalable infrastructure: Warming one domain or managing dozens of sending accounts? Warmy’s infrastructure handles the complexity of maintaining high deliverability across multiple domains. Warmy integrates with all major email providers (Google Workspace, Outlook, SMTP) and works alongside your existing cold email tools. With a Workspace Management feature, managing multiple domains is efficient and seamless.
Ready to improve your inbox placement? Try Warmy.io for free and see where your emails are actually landing.
FAQ
How much do cold email agencies charge?
Cold email agency pricing varies by scope. Email-focused agencies typically charge $1,500-$5,000 per month. Omnichannel agencies that combine email, phone, and LinkedIn generally run $5,000-$15,000 per month. Enterprise-level services with AI platforms and dedicated SDR teams can exceed $10,000 per month plus setup fees. Some agencies also offer pay-per-lead or pay-per-meeting pricing for more predictable costs.
How long does it take to see results from a cold email agency?
Most agencies need 2-4 weeks for setup, including domain warmup, list building, and copy approval. Initial meetings typically start arriving within 1-2 weeks after campaign launch. Expect 60-90 days for full optimization and consistent, predictable results. Agencies that promise immediate results without a warmup period may be cutting corners on deliverability.
Do cold email agencies handle email warmup and deliverability?
Reputable agencies handle warmup and deliverability infrastructure as part of their service. This includes setting up dedicated sending domains, configuring SPF, DKIM, and DMARC authentication, and warming domains for 2-4 weeks before launching campaigns. Many agencies use specialized warmup tools to maintain inbox placement rates throughout active campaigns.
Should I choose an email-only agency or an omnichannel agency?
Email-only agencies are best for straightforward B2B sales where email alone drives conversions; they’re more affordable and faster to launch. Omnichannel agencies that add phone and LinkedIn work better for complex sales cycles, high-value enterprise deals, or when targeting executives who are difficult to reach through a single channel.
Will hiring a cold email agency hurt my domain reputation?
Not if you choose a reputable agency. Professional cold email agencies never send from your primary domain. They set up separate sending domains with proper DNS authentication and warm those domains before launching campaigns. This isolates your outreach activity from your main business email, protecting your primary domain reputation.
What is the difference between done-for-you and SDR-as-a-Service?
Done-for-you agencies manage the entire outreach process independently. You receive booked meetings without involvement in the day-to-day campaign. SDR-as-a-Service provides dedicated sales development representatives who function as an extension of your internal team, requiring more coordination and oversight from your side. DFY is hands-off; SDRaaS involves more collaboration.
What is the best cold email agency for B2B companies?
OutreachBloom is a strong fit for small to mid-size B2B companies because they specialize in email-only outreach with a fully managed model that doesn’t require hiring SDRs or managing infrastructure. Their focused approach keeps costs lower than omnichannel agencies while handling everything from domain setup and warmup to reply management.
