The actual difference
A CMO owns how the market perceives you and every channel that shapes it. A Head of Growth owns a number, usually revenue or activated users, and is judged on whether it moves. One is a portfolio job, the other is a delivery job. That is the whole distinction, and most of the confusion comes from companies writing one title on the req and describing the other in the bullet points.
I have held the Head of Growth seat four times, most recently at Superpower, and I have reported into CMOs and replaced them. The roles fail differently. A bad CMO produces beautiful strategy and no pipeline. A bad Head of Growth produces forty experiments and no compounding channel. When you know which failure you are more afraid of, you know which role you need. The full scope of the growth seat is in what a Head of Growth actually does.
Which one you need, by stage
The honest test is whether you have a growth system that needs an owner, or a growth task that needs a doer. A system with revenue flowing through it, paid channels, a funnel, a lifecycle program, needs an owner who can prioritise across it. That is the growth seat. A brand that nobody knows, a category you need to define, a story investors and candidates need to hear, that is the CMO seat.
Most companies reach for a Head of Growth about a year too early or a year too late. Too early means there is no product-market fit for the person to scale, and they burn out running experiments on a leaky product. Too late means the founder has been the de facto Head of Growth for two years and the channels have calcified around their instincts.
My contrarian read after doing both dances: below about 30 people you almost never need either as a full-time hire. A fractional CMO plus a fractional Head of Growth covers everything a business at that stage needs, with specialist contractors underneath. The full-time versions make sense when the coordination cost of fractional people exceeds their salary gap, which happens later than founders think.
What the money and scope look like
The seats also differ in what they control. As Head of Growth I typically ran the performance budget and about $100k a year in software decisions, CRM, analytics, testing tools, while the CMO ran brand, comms and agency spend several times larger. If the budget you most need spent well is media and tooling, that tells you something. If it is positioning and reputation, that tells you the other thing.
Pay bands overlap but the shapes differ, and I keep the current Australian numbers on the salary page. If you have decided the growth seat is the one you need, here is how to hire for it, and here is who is genuinely good at it in Australia. If you are still deciding, the difference between growth marketing and traditional marketing is the same distinction one level down.
FAQ
Is a Head of Growth more senior than a CMO?
No. A CMO is usually the more senior title, owning brand, comms and the whole marketing function. A Head of Growth owns a specific number and the experiments that move it. In small companies the Head of Growth often runs everything and the distinction collapses.
Can one person do both jobs?
Below about 30 people, yes, and usually fractionally. A fractional CMO plus a fractional Head of Growth covers what most early companies need. Past that, the portfolio job and the delivery job start crowding each other out.
Which should a startup hire first?
Whichever failure you fear more. If nobody knows you exist, the CMO problem comes first. If people arrive and do not convert or stick, the growth problem comes first. The honest test: do you have a growth system that needs an owner, or a growth task that needs a doer?