This question usually gets answered with a gut feeling instead of a real number. "An agency sounds expensive" and "hiring in-house gives me more control" are both true in the way they feel, and both skip half the real cost.
The in-house number is bigger than the salary
A junior SDR salary looks affordable on its own. Payroll taxes and benefits typically add 20 to 30% on top of base pay. A laptop, a phone line, a sales engagement tool seat, a data or list-building subscription and a CRM seat all add recurring cost regardless of whether that SDR books a single meeting in month one. Add recruiting time and, if the hire does not work out, the cost of re-hiring. The real first-year cost of one in-house SDR routinely runs 1.5 to 2 times the number people quote as "the salary."
The ramp-up tax nobody budgets for
A new SDR, even an experienced one, does not perform at full capacity on day one. Learning your product, your ICP, your objection handling and your tools typically takes 4 to 8 weeks before volume and quality both land where they need to be. During that window you pay full cost for partial output. An agency that has already built the list-building process, the sequence templates and the qualification criteria for other clients compresses that ramp, because the infrastructure already exists.
What an agency fee is actually buying
A monthly retainer buys the finished output of several roles at once: a researcher who builds and maintains the prospect list, a copywriter who writes and iterates the sequences, someone managing sending infrastructure and deliverability, and a layer of oversight keeping all of it on track. Hiring each of those separately in-house costs far more than one SDR salary.
Where in-house genuinely wins
In-house makes sense when outbound is a long-term, core, scaling function, not a lead-generation channel: a team of five or more built and kept over multiple years compounds process and market knowledge that an external team cannot match. It also wins when the sale is complex enough that only someone embedded full-time in your product and your deals can credibly open conversations for it.
Where outsourcing genuinely wins
Outsourcing wins when you need pipeline now and do not have 2 to 3 months to spend on hiring and ramp, when volume needs to flex up or down with a specific campaign rather than running as permanent headcount, or when researching prospects, writing sequences and managing deliverability is not a skillset you want to build internally at all. It is also the lower-risk way to test a new market or offer: an agency engagement can be paused in a month, a hire cannot.
The honest framework
Run the comparison on 12-month cost, not monthly cost: fully loaded in-house salary plus tools plus the ramp-up period at reduced output, against a full year of agency output from month one or two. Then separate that from the strategic question of whether outbound needs to be a permanent internal capability or a channel you turn on and tune.
How we handle it
ColdConnect runs as the second model: a monthly retainer that replaces the research, copywriting, sending and deliverability work of a small team, live within weeks instead of months, and easy to scale up, pause or stop as your plans change.