A fractional head of growth is a senior growth leader who runs your measurement, strategy, and execution part-time, for a fraction of a full-time hire. An agency executes campaigns against a brief. An in-house hire owns the function full-time but takes months to source and ramp. The right choice depends on stage, budget, and whether you need decisions or just execution.
- Fractional leaders own decisions; agencies execute briefs; in-house hires own the function long-term.
- The hidden cost of a bad in-house growth hire is usually six figures once ramp, mis-hire, and opportunity cost are counted.
- Most growth-stage companies get further faster by pairing a fractional leader with specialist agency execution.
- The right sequence is often fractional first, then in-house once the playbook and metrics are stable.
What is a fractional head of growth?
A senior operator embedded in the business, typically two to three days a week, with real authority over measurement, budget allocation, and roadmap. Retainer-based. Outcomes-oriented. Ships work the way a full-time VP of Growth would, without the burdened cost or the hiring risk.
What does an agency actually do?
An agency executes a specific scope against a brief the client provides. Paid media, SEO, lifecycle, or creative production. The best agencies are excellent at their craft but rarely own strategy, cross-channel measurement, or the underlying revenue systems. They optimize what they are given, not what should exist.
What does an in-house hire own?
A full-time head of growth owns the function permanently: hiring the team, running the roadmap, defending the budget, and answering to the board. It is the right end state for most companies. The cost is compensation, equity, ramp time, and the risk of a mis-hire in a role that is notoriously hard to interview for.
How do the three actually compare?
| Dimension | Fractional Head of Growth | Agency | In-House Hire |
|---|---|---|---|
| Cost | $5–20K/mo retainer | $5–50K/mo per scope | $250–400K all-in per year |
| Time to start | 1–2 weeks | 2–6 weeks | 3–6 months to hire |
| Ramp | Productive in days | Productive in weeks | Productive in quarters |
| Ownership | Owns decisions & outcomes | Owns delivery of scope | Owns function long-term |
| Breadth of skill | Full stack: strategy, data, execution | Deep in one channel | Depends on the individual |
| Risk | Cancel monthly; low switching cost | Channel-locked; misaligned incentives common | Mis-hire cost is 6-figure |
| Best-fit stage | Seed → Series B, or pre–VP transition | Any stage with a clear brief | Series B+ with a stable playbook |
When does each option win?
Fractional wins when the growth function needs to be built or rebuilt, when leadership needs a partner who can make decisions, and when the budget for a full-time VP is not yet justified. Agencies win when the strategy is set and a channel needs specialist execution. In-house wins when the playbook is stable, the metrics are trusted, and the company is ready to hire a team under a permanent leader.
What is the hidden cost of a bad in-house growth hire?
Compensation is the visible number. The hidden costs are six to nine months of slow decisions, a marketing budget spent against the wrong hypotheses, board confidence eroded, and a severance package on the way out. Industry estimates put the fully loaded cost of a mis-hire at three to five times base salary. For a $200K base, that is $600K to $1M of value destroyed.
How does mxdify fit?
mxdify operates as a fractional growth leadership function with an execution team behind it. We run measurement, revenue systems, and experimentation as one program, and we hand off a documented playbook when a full-time hire is ready to take it over. In most engagements, we also write the job description and interview loop for that eventual hire.
