You’ve raised. Your investors are asking about pipeline. You know you need outbound to work — but you’re not sure whether to hire a sales development rep or outsource the whole thing to an agency. Both options seem plausible. Both have advocates. And most of the content on this topic is written by people with an obvious stake in one answer.
This isn’t that. We run an outbound agency, which means we have a financial interest in you choosing option B — and we’re going to say that upfront, because the honest answer is that it depends on your specific situation, and getting it wrong costs you 6–12 months of wasted time and money. So here’s an actual breakdown.
The Real Cost of Hiring an SDR
Most founders dramatically underestimate what a sales development rep actually costs. The salary is only part of it.
A junior SDR in the US (0–2 years experience) earns $45,000–$60,000 base. A UK equivalent is £28,000–£38,000. Add 20–30% for employer taxes, benefits, and pension contributions. Add your recruiting cost — either 15–20% of first-year salary through a recruiter, or the equivalent in founder time on LinkedIn and interviews. Add the tools they need: a sequencing platform, enrichment credits, CRM licences, LinkedIn Sales Navigator. Add 60–90 days of ramp time before they’re operating independently.
The fully-loaded cost of a junior SDR in the US, including ramp, recruiting, tools, and taxes, is typically $7,000–$10,000 per month for the first six months. In the UK, £4,500–£6,500/month equivalent.
That’s before you account for management overhead. A first SDR hire needs close coaching — on calls, on messaging, on pipeline hygiene. If you’re the one doing that, you’re spending 5–10 hours per week on it. If you’re not, results suffer.
The Real Cost of Outsourcing Outbound
An outbound agency or done-for-you service typically charges in one of two ways: a setup fee (one-time) and a monthly retainer, or a flat monthly fee covering both.
At the lower end of the market, you’ll find offshore freelancers and low-cost services charging $500–$1,500/month. These generally use templated sequences, minimal personalisation, and shared infrastructure. Results are inconsistent.
Mid-tier specialist agencies — the category GrowthStack sits in — charge a setup fee of $2,000–$4,000 for infrastructure and onboarding, followed by a monthly retainer of $1,500–$3,000. Total year-one cost: $20,000–$40,000. That’s roughly 25–40% of the SDR route, for comparable or better output in the first 6 months.
High-end agencies (former in-house teams, enterprise-focus) charge $8,000–$15,000/month. Rarely the right fit for pre-Series A companies.
The Decision Matrix
Here’s how to think about which option fits your situation right now:
Outsource outbound if…
- You’re pre-Series A and haven’t yet proven your outbound motion works
- You don’t have a repeatable sequence, tested ICP, or validated messaging — the agency helps you build and test this
- You need pipeline in the next 60–90 days, not 6 months
- You don’t have time (or desire) to manage and coach an early-career sales hire
- You want a known monthly cost with no recruiting risk
- Your ACV is $5,000+ per year — the economics of outsourced outbound work when one closed deal covers several months of retainer
Hire an SDR if…
- You’ve already proven your outbound motion and need to scale it with more capacity
- You have an experienced sales leader in-house who can coach and manage the SDR from day one
- Your ACV is low (sub-$3,000/year) — the unit economics of an agency retainer won’t stack up
- Your sales process requires deep product knowledge that takes months to build — making a ramp-intensive hire worth the investment
- You’re planning to build a sales team in the next 12 months and want the first SDR to become a team lead
Do it yourself if…
- You’re pre-product or pre-revenue — talking to potential customers is founder work, not SDR work at this stage
- You haven’t yet identified your ICP — no agency or SDR can fix undefined targeting
- You genuinely enjoy the process and have cycles to spare — some founders are exceptional at this
The Hidden Risk Nobody Talks About
There’s a failure mode that costs founders 6–12 months that nobody in either camp discusses honestly: hiring an SDR before you have a working outbound system.
Most early-stage SDR hires are given a CRM login, a list of target companies, and told to figure it out. They set up sequences themselves. They choose their own subject lines. They define the ICP based on whatever they learned at the last company. Three months later, the pipeline is thin, the founder is frustrated, and the SDR is either let go or demoralised.
The value of outsourcing in the early stage isn’t just the execution — it’s that a good agency brings a working system: a proven infrastructure, validated sequence structures, an ICP definition process, and tooling that already works. When that system produces results, you can take it in-house with an SDR hire. The agency has de-risked the build.
That’s roughly the model GrowthStack operates on: a GTM Foundation phase that builds and validates the system, followed by ongoing management or handoff — whichever makes more sense at your stage.
Side-by-Side Comparison
To make the above concrete, here’s a direct comparison across the dimensions that matter most for an early-stage B2B founder:
- Time to first meeting: Agency — 2–4 weeks from kickoff. SDR — 8–14 weeks from hire (recruiting + ramp).
- Year 1 cost: Agency (mid-tier) — $25,000–$40,000. SDR (US, fully loaded) — $80,000–$110,000.
- Management overhead: Agency — 1–2 hours/week on calls and review. SDR — 5–10 hours/week coaching and managing.
- Risk: Agency — locked into a retainer that may not work. SDR — 90-day notice period, recruiting cost, ramp risk.
- Scalability: Agency — limited by scope and retainer. SDR — can grow into a team; builds institutional knowledge.
- System ownership: Agency — they own the process unless you specify otherwise. SDR — you build internal capability over time.
The honest summary: For most pre-Series A B2B founders who haven’t yet proven their outbound motion, outsourcing is the lower-risk, lower-cost, faster path to pipeline. Once you have proof — once you know the ICP, the sequence, and the conversion benchmarks — an SDR hire makes sense. Do it in that order.
Questions to Ask Any Agency Before You Sign
If you decide to go the agency route, don’t just compare prices. Ask these questions before signing anything:
- Who actually runs the campaigns — a senior person or a junior coordinator?
- What does the onboarding process look like, and how long before the first campaign is live?
- What are your typical reply rates, and what benchmarks should I expect in my vertical?
- Do you own the infrastructure (sending domains, inboxes), or do I?
- What happens to the system if I end the retainer — do I keep everything?
- Have you worked with companies at my stage and in my industry?
A good agency will answer all of these clearly. If an agency hedges on any of them — especially on benchmarks and who does the work — treat that as a signal.
For context on how GrowthStack answers these questions: the campaigns are run by the people you speak to in the discovery call, not junior staff. We build the infrastructure on your accounts so you own it. And our first phase is a fixed-scope setup that gives you a working system whether you continue with us or not. Here’s how it works in full.
Not sure which route is right for you?
Book a 30-minute call. We’ll tell you honestly whether GrowthStack is the right fit — and if not, what we’d recommend instead.