Choosing an outbound agency is a high-stakes decision that most buyers make on weak evidence.
Logos on a homepage, a Clutch score, and a confident sales call all correlate loosely with whether meetings show up on your calendar in month three.
What predicts results is narrower.
Whose infrastructure you send from, how they source and qualify, what counts as a "meeting" in the contract, and whether they'll tell you when your offer is the problem.
This list covers the agencies buyers compare most often, scored on those criteria. Every entry gets the same treatment: what they're best at, what the review record shows, and one honest limitation.
Disclosure: IntentLedSales builds and runs outbound engines for B2B agencies and SaaS companies, so we're the first entry below. We've written our own entry to the same standard as everyone else's, limitation included.
Score any agency against these six things
They're ordered by how often each one turns out to be the thing that went wrong.
| Criterion | The question | Why it matters |
|---|---|---|
| Infrastructure ownership | Whose domains and mailboxes do we send from? | Sending from your primary domain can damage an asset you can't replace |
| Meeting definition | What exactly qualifies, in writing? | The biggest source of retainer disputes |
| Sourcing method | Can you see the filters and signals? | Firmographic-only lists cap performance regardless of copy |
| Data ownership | Who keeps the lists at the end? | Determines whether you're building an asset or renting one |
| Iteration policy | If month one flops, what changes? | Agencies that keep sending an unproven offer are burning your list |
| Client concentration | How many others in my category? | Direct competitors sharing a vendor share a message |
Two things that look like signals and aren't.
Case studies are unverifiable and selected. Team size correlates with overhead, not output.
Ask instead to speak to a client they stopped working with. The answer to that request tells you more than the reference call itself.
The shortlist at a glance
| Agency | Best for | Primary channel | Pricing signal |
|---|---|---|---|
| IntentLedSales | Signal-led outbound you end up owning | Email + LinkedIn, AI reply agent | Free pilot, then pay per meeting held |
| Belkins | Deepest verified review base | Email + LinkedIn | Unpublished; reported $5k-$15k/mo |
| Martal Group | Cross-industry omnichannel, sales outsourcing | Omnichannel | Custom, tiered |
| SalesRoads | US-based phone-first appointment setting | Cold calling + email | From ~$6,000/mo |
| Callbox | Multi-region campaigns, strong in APAC | Omnichannel | Regional pods from ~$15,000/mo |
| CIENCE | Enterprise volume with proprietary data | Multichannel | From ~$5,000/mo |
| Leadium | Boutique research quality at a low entry point | Email, phone, LinkedIn, SMS | From ~$1,000/mo |
| Cleverly | A cheap single-channel LinkedIn test | Under $1,500/mo |
1. IntentLedSales
Best for: B2B agencies and SaaS companies doing $20K to $500K a month who want outbound built on buying signals rather than firmographic lists.
We run done-for-you outbound on a single thesis: most campaigns fail on timing, not copy.
Lists get sourced off observable triggers such as tech stack matches, funding, hiring posts and competitor engagement, layered over niche directories and lookalike modelling.
The build covers infrastructure, then an A/B matrix testing offers against ICP segments until one combination converts.
Then ongoing management with a dedicated strategist, an AI reply agent, and a setter working positive replies.
Model: a free pilot campaign first, then ongoing management where you only pay for meetings that show up. Domains, mailboxes, lead lists and dashboards stay yours and transfer on request.
Pricing: discussed on the qualification call. Capped at five new clients a month.
Proof: 40+ B2B companies. One healthcare operations client generated $532K in qualified pipeline in three months. A 130-person marketing agency in a saturated niche added $150K+ in revenue in two months at 3-6 positive replies a day.
Honest limitation: the model works best above roughly a $3,000 average deal size, and the client cap means availability moves month to month. Worth applying early if timing matters to you.
2. Belkins
Best for: done-for-you appointment setting where personalisation matters more than raw volume.
Founded in 2015, Belkins works across 50+ industries through an email-and-LinkedIn-led motion. Accounts are typically staffed as a pod rather than from a shared resource pool.
Review record: 4.9 on Clutch from 230+ reviews and 4.8 on G2, with clients including NVIDIA and Autodesk. That's the deepest verified review base in this comparison.
Pricing: not published. Third-party reports put full-service retainers somewhere between $5,000 and $15,000 a month.
Honest limitation: the recurring criticism in buyer reviews is cost. It's a premium option, and if you want published pricing before a discovery call you'll find the process frustrating.
The service footprint has also expanded well past outbound into SEO, events and paid, so pin down exactly which channels and which people are inside your engagement.
3. Martal Group
Best for: cross-industry omnichannel work, and buyers who want sales outsourcing rather than just meeting-booking.
Martal runs campaigns across 50+ verticals with 2,000+ B2B brands served, and consistently ranks at or near the top of Clutch's lead generation category.
The motion blends outbound execution with sales development support, which suits teams wanting someone to carry a conversation past the calendar invite.
Pricing: custom, tiered by scope.
Honest limitation: the breadth that makes it flexible also makes it harder to evaluate. With 50+ verticals in the portfolio, ask specifically who has run campaigns in your category and how recently.
If your gap is people rather than a targeting system, this is the right shape. If it's the reverse, it may not be.
4. SalesRoads
Best for: phone-first outbound into industries where decision-makers respond better to a conversation than a sequence.
Running since 2007 and headquartered in Florida, SalesRoads staffs US-based callers rather than offshore volume, and pitches a consultative style with a strong QA process.
It specialises in manufacturing, logistics, healthcare IT and financial services.
Review record: 4.9 on Clutch from 65 reviews as of June 2026, and 4.8 on G2.
Pricing: retainers from around $6,000 a month for a dedicated SDR, with appointment-setting programmes reported closer to $9,500 per four weeks.
Honest limitation: phone-led programmes carry the highest cost per touch in outbound. Confirm your contract value supports a high-touch model, because under roughly $15k ACV the math gets difficult.
5. Callbox
Best for: enterprises coordinating account-based programmes across multiple regions, particularly with APAC requirements.
With over twenty years of operation, Callbox has the strongest multi-region infrastructure on this list, covering calling, email and social with full-funnel nurture.
Running consistent outbound across North America, Europe and Asia from separate vendors is an operational headache most teams underestimate, and this is the clearest solution to it.
Pricing: regional pods are reported from around $15,000 a month per region.
Honest limitation: that pricing structure makes sense for enterprises running three regions and prices out nearly everyone else.
Multi-region delivery also means distributed teams, so ask which region your programme is actually staffed from rather than which regions they can target.
6. CIENCE
Best for: companies needing high-volume outreach at scale with proprietary data tooling underneath it.
CIENCE is one of the largest SDR-as-a-service providers in B2B, with its own data and intelligence platform, meaning sourcing and execution sit under one roof. It merged with Tenbound in 2025.
Review record: this is where it diverges from the field. 3.8 on G2 from 188 reviews and 4.2 on Clutch from 142, against 4.8 or higher for most others here.
Buyer feedback splits: strong on sales performance and team effectiveness, weaker on customer support and lead quality.
Pricing: retainers from approximately $5,000 a month depending on team size and channel mix.
Honest limitation: scale is the product, which cuts both ways. If your ICP is narrow or technical, press hard on how much genuine research goes into each account versus how much is templated at volume.
7. Leadium
Best for: buyers who value research curation over volume, at an entry point most agencies can't match.
Leadium runs full-service sales outsourcing across email, phone, LinkedIn, SMS and strategic gifting, with manual research and rigorous ICP definition as stated priorities.
The workflow is collaborative in a way that's genuinely unusual. The client approves the target list before campaigns launch.
Pricing: from around $1,000 a month minimum, with flexible retainers by scope.
Honest limitation: the boutique model means limited capacity, and curated research doesn't scale the way automated list-building does.
If you need thousands of contacts a month rather than hundreds of well-chosen ones, this isn't the shape you want.
8. Cleverly
Best for: testing whether LinkedIn outreach works for you before committing real budget.
Cleverly runs LinkedIn-led campaigns as a single channel, with published pricing starting under $1,500 a month.
That makes it the cheapest legitimate way on this list to find out whether your offer lands on a warm channel, without standing up email infrastructure first.
Pricing: published plans, under $1,500 a month at entry.
Honest limitation: single-channel by design. LinkedIn is rate-limited to roughly 80 to 100 connection requests a week per account, so the ceiling arrives fast.
Treat it as a test rather than a pipeline engine.
If you're a SaaS company, weight these differently
The motion changes enough that the criteria shift.
The product is the offer. The best SaaS outbound doesn't sell a subscription in the email. It sells the smallest possible experience of the product: a workflow built in their account, an extended trial, a report from their own data.
Ask a prospective agency what micro-offer they'd construct from your product. If the answer is "we'll book demos," you're getting a services playbook run on a software company.
Sourcing is harder than it looks. Generic industry filters return only 30 to 40% actual software companies, with the rest being agencies and IT consultancies.
Ask specifically how they build SaaS lists. "Apollo with the software filter" is the wrong answer.
The best signals are technographic. Detecting a competitor's script on a prospect's site proves the buying decision has already been made once, which makes it the highest-converting signal available to you.
An agency that can't detect technographics is leaving your strongest targeting lever unused.
Measure past the meeting. A booked demo is a leading indicator. What matters is trial starts from cold, activation rate, and PQL-to-opportunity conversion.
Agree those metrics before signing, or you'll spend month four arguing about whether 30 demos that never activated counts as success.
When not to hire anyone
Worth reading before you take a single sales call.
Your ICP isn't defined. You'll pay a vendor to figure it out and get a worse answer than you'd have reached yourself.
You have no message-market fit. Outbound will only tell you faster that the offer isn't landing.
You can't staff the closing side. A full calendar with nobody to work it is an expensive vanity metric.
Your contract value is under roughly $2,000. The economics rarely clear, whoever runs it.
Five questions for every discovery call
- What exactly qualifies as a meeting, and what show rate do you deliver?
- Whose domains and mailboxes do we send from?
- Who owns the lead data and campaign assets if we part ways?
- What's your sourcing method, and can I see the filters?
- If month one doesn't land, what changes: the offer, the list, or nothing?
Question two is the one buyers skip and regret. Question five separates agencies that iterate from agencies that just keep sending.
Frequently Asked Questions
How much do outbound agencies cost?
Email-only programmes run roughly $1,000 to $5,000 a month. Full-service omnichannel with dedicated SDRs runs $5,000 to $15,000. Enterprise engagements with multi-region pods exceed that. Performance pricing typically lands at $150 to $600 per booked meeting for SMB targets, rising past $2,500 for enterprise.
How long before meetings appear?
Most agencies need two to four weeks for setup, covering domain warming, list building and messaging approval. First meetings typically appear 30 to 60 days after launch. Any vendor promising results in week one is either skipping warm-up or sending from infrastructure whose damage you'll inherit.
Should I pick an agency that specialises in my industry?
It helps, but less than buyers assume. What matters more is whether they can build a list on a real buying signal in your market. A generalist who sources on technographics will beat an industry specialist running firmographic lists.
What's the difference between lead generation and appointment setting?
Lead generation often stops at contact data or top-of-funnel interest. Appointment setting runs the outreach, qualifies against your criteria, and places a confirmed meeting on your calendar. Many vendors do both, and the handoff between them is exactly where quality is won or lost.
How to actually choose
There's no best agency, only best fit, and the fit is usually decided by three things.
Your budget tier, because $1,500 and $15,000 buy structurally different products.
Your channel, because phone-first and email-first agencies aren't interchangeable. And whether your gap is people or system, because those need opposite solutions.
Work out which of those three is your real constraint before the first call. It'll narrow this list to two names faster than any comparison table.
