B2B businesses today are fighting an uphill battle. Budgets are tighter, buying teams are bigger, and inboxes are flooded with surface-level outreach.
In a market like this, it’s no wonder the “full service” label starts to feel meaningless. Every B2B sales and marketing agency claims they “do it all,” but few truly understand tech buyers and can solve your pipeline problems.
If you sell SaaS, cybersecurity, data infrastructure, or anything with a complex sales cycle, you need an agency that feels like a natural extension of your team, translating value to technical and business stakeholders. That’s why we built this guide to help you transparently evaluate potential partners. These standout agencies combine technical fluency with flexible service models, while focusing on results that matter, from B2B prospecting to closing.
Here are our top picks for B2B sales and marketing agencies in 2025, why Inside Sales Solutions leads the pack, and how others compare.
What Makes a Great B2B Sales and Marketing Agency
You need to partner with a B2B sales and marketing agency that can help your pipeline with dedicated sales development outsourcing services, appointment setting services, and lead qualification. But how can you tell the “good” from the “great?”
Here’s how:
- Tech fluency: Excellent agencies don’t just “get” technology—they breathe it. Agencies working in spaces like SaaS, IT services, cybersecurity, big data, and networking need to be able to translate feature sets into outcomes, and know the difference between a data architect and a VP of IT. Expect credible experience, persona-specific messaging, and the ability to easily navigate long, multi-stakeholder cycles.
- Pipeline obsession: The right partner focuses on real results (like meetings and revenue), not vanity metrics. Look for clear service level agreements (SLAs) like qualified meeting definitions, tight CRM hygiene, call recordings for QA, and regular feedback loops that allow for iteration based on what actually converts.
- Flexible models: Your buying cycle, seasonality, and territories dictate the engagement you need. With that in mind, a top agency lets you choose between different models, like dedicated SDRs, pay-for-performance, or hybrid. This allows you to avoid risk, scale up or down as needed, and support your in-house team when it matters (like during launches and events).
This is the bar we hold ourselves to here at Inside Sales Solutions, and the lens we use to evaluate our top picks.
Inside Sales Solutions vs. Other B2B Sales Agencies
Many outsourced B2B sales and marketing agencies claim to offer “full service.” But few bring the things to the table that actually set them apart from the rest.
Why ISS leads the pack:
- SDR as a service (with flexibility): These inside sales outsourcing options (dedicated, retainer, pay-for-performance) let you avoid risk and choose a model that meets your needs. Here at ISS, we offer dedicated, retainer, or pay-for-performance models.
- Cold calling expertise: ISS leads with human-first outreach, supported with a multi-channel approach (where many competitors lean on automation alone). Studies show that cold calling services are still powerful for effective outreach, with nearly half of reps saying it’s either their primary or secondary sales channel.
- Human-verified database: With ISS, no dials are wasted. We maintain a proprietary, continuously updated database (that includes working mobile numbers) for higher connect rates.
Bottom line: If your goal is to book meetings, maintain a full pipeline, and have more warmed leads primed to close, ISS is built to deliver.
Here’s how Inside Sales Solutions stacks up against other well-known agencies in the space:
| Agency | Strengths | Limitations (vs. ISS) |
| Inside Sales Solutions | Flexible SDR models (dedicated, retainer, pay-for-performance), cold calling expertise, human-verified database, live scheduling | N/A (ISS is the benchmark) |
| BAO | Appointment setting at scale | Lacks flexibility, focused mainly on volume |
| Memory Blue | SDR recruiting and training pipeline | More staffing-focused than a full-service partner |
| Reveneer | Retainer-only SDR teams | Rigid model, less emphasis on live cold calling |
| AltiSales | Startup-focused SDR outsourcing | Automation-heavy vs. ISS’s tailored, human-first approach |
| CIENCE | Data + SDR services | Leans heavily on automation, less about real conversations |
Curious to see how ISS stacks up against other well-known agencies?
Here’s a brief overview:
- BAO: BAO, or “By Appointment Only,” offers appointment setting and custom lead generation solutions for sales and marketing. They can help you set appointments at scale, using performance-based models. However, they tend to be less flexible, offering solutions that are optimized for volume over precision and learning loops.
- memoryBlue: This agency helps public sector and tech organizations fill their pipeline and hit sales targets, using their SMART approach—Sales, Marketing, Academy, Recruiting, and Technology. While they offer deep SDR recruiting and training pipeline services, they tend to be more staffing-focused, rather than a full-service, outcomes-owned partner.
- Reveneer: Reveneer has a “proven, precisely engineered process” to help achieve inside sales results. They leverage well-trained teams, data-driven insights, and their tech-enabled sales engine to start conversations and drive the pipeline. While they do offer retainer-based SDR team services, Reveneer provides a rigid model with less emphasis on live, human-led cold calling.
- AltiSales: AltiSales is a B2B go-to-market agency that offers SDR services, consulting, and more. Their services are tailored to startups and fast-growing businesses (for example, they have a range of packages at different price points). However, they’re heavier on automation when compared to ISS’s tailored, human-first approach.
- CIENCE: This B2B lead generation agency and service blends AI and human expertise to help you achieve your pipeline goals. However, they rely heavily on automation, resulting in fewer genuine conversations with technical buyers.
Takeaway: While competitors often rely on rigid models or automation, Inside Sales Solutions blends flexibility, proven cold calling expertise, and a prescriptive, human-first approach to consistently deliver a quality pipeline.
Questions to Ask Before Choosing an Agency
To choose the right B2B sales and marketing agency for your business, consider asking them these questions to find a partner that will help you achieve your B2B sales pipeline goals.
1. How Do You Define Success: Booked Meetings or Impressions?
If they lead with vanity metrics like clicks or opens, keep probing. A better answer ties activity to qualified meetings, show rates, and pipeline, with clear SLAs.
2. Can You Integrate Seamlessly into Our CRM and Sales Stack?
Your existing tech infrastructure matters. Ask your potential partner about specifics, such as Salesforce/Hubspot objects, routing rules, call recordings, and reporting. You want clean, visible data.
3. What’s Your Fluency in B2B Tech?
Generalists won’t be able to speak the language of your savvy buyers. Listen for persona-led expertise, and how your potential partners navigate spaces like SaaS, cybersecurity, and data.
4. What Outreach Mix Do You Use?
Look for a phone-first approach, combined with email/LinkedIn—not just automation-only sequences.
5. Which Engagement Models Do You Offer?
You should be able to choose from dedicated, retainer, pay-per-performance, or hybrid to meet your needs.
Your Pipeline Deserves a Partner, Not Just a Vendor
If you’re selling B2B products in complex spaces to technical buyers, the sales and marketing agencies you partner with matter.
You need an agency that brings tech fluency, flexible SDR as a service, real cold-calling expertise, and human-verified data to the table. While competitors might deliver outreach volume, Inside Sales Solution delivers a high-quality pipeline that actually closes.
Ready to stop chasing leads that go nowhere? Partner with an agency that actually gets tech buyers.
Talk to Inside Sales Solutions today to see how our tailored, cold calling-first approach can strengthen your outbound efforts and get qualified meetings on your calendar.