The comparison most businesses get wrong
The usual comparison is a salary against a retainer, which is not a like-for-like measurement.
An honest in-house cost includes: salary, statutory costs, tools and subscriptions, training, equipment, recruitment cost, the management time of whoever directs them, and the risk that the hire does not work out and the search restarts.
An honest agency cost includes: the fee, the coordination time you spend, and the ramp-up period before they understand your business.
Only after both are stated fully can the decision be made on evidence rather than on the appearance of the two numbers.
What in-house genuinely does better
- Product and customer depth. Someone in the building absorbs context that no external partner will match.
- Availability. Immediate response to internal needs.
- Institutional memory. Knowledge accumulates in your organisation instead of leaving with a contract.
- Cross-functional work. Coordination with sales, operations, and service is easier from inside.
- Cost efficiency at high volume. Once the workload is continuously full, in-house is usually cheaper per unit of output.
What agencies genuinely do better
- Multiple specialisms in one engagement. Performance media, design, development, copy, and production rarely coexist in one hire.
- Speed to capability. Weeks to start rather than months to hire.
- Pattern recognition across accounts. They have seen your problem in other businesses.
- Elastic capacity. Launches and seasons scale up without permanent headcount.
- Tooling and process already paid for and established.
The honest weaknesses of each
In-house risks: a single person cannot be excellent at strategy, design, media buying, and development simultaneously; skills stagnate without exposure; one departure can halt everything; and an unmanaged marketer with no senior direction usually drifts to activity rather than outcomes.
Agency risks: context is shallower, priorities compete with other clients, junior staff may execute what senior staff sold, and accountability blurs when they own only one part of the chain.
A decision framework
Answer these five questions:
- Is the work continuous? Continuous, predictable workload favours in-house. Variable, project-shaped work favours partners.
- How many specialisms are required? More than two suggests a partner or a small team, not one hire.
- Who will direct them? An in-house marketer with no experienced direction usually underperforms regardless of talent. If nobody can set direction, buy direction.
- How specific is your domain? Highly technical categories with long learning curves favour in-house depth.
- What happens when they leave? Consider continuity for both options — documentation, access, and handover.
The hybrid that most growing businesses land on
One capable in-house person who owns strategy, brand knowledge, coordination, and the customer relationship, supported by specialists for media, design, development, and production.
This works because the scarce resource is context plus coordination, and the elastic resource is execution capability. It also gives you an internal owner who can hold partners accountable in an informed way — which is the failure point of pure outsourcing.
Protecting yourself either way
Regardless of the model:
- Every account — domain, hosting, analytics, ad platforms, CRM, social — registered in the business's name with you as owner.
- All creative source files delivered and stored by you.
- Documentation of processes, not just outputs.
- Reporting you can reproduce independently.
- An exit clause and a handover expectation written before the relationship starts.
These are not signs of distrust. They are the difference between a partner change costing a week and costing a quarter.
Signals it is time to change the model
Bring more in-house when: you are paying for continuous work that never varies, your partner's context gap causes rework, or the coordination burden has grown larger than the execution.
Bring in partners when: your in-house person is stretched across specialisms they cannot all do well, you need capability faster than you can hire, or a launch demands surge capacity.
The underlying question
The choice is not really agency versus in-house. It is: who owns the growth system, and do they have both the context and the capability to run it?
Answer that, and the staffing model usually becomes obvious.
