Fractional CMO vs a marketing agency: which do you need?

An agency executes within a channel; a fractional CMO owns the strategy and outcome above it, and often ends up briefing the agency too.


6 min read
Fractional CMO · Agencies

By Jo van Vuuren — Fractional CMO

Ask whether you need a fractional CMO or a marketing agency and you have usually already skipped a step. They are not two versions of the same service. An agency executes within a channel: the campaigns, the content, the media buying. A fractional CMO owns the strategy and the commercial outcome above it, and very often ends up briefing and managing the agency, not replacing it.

What an agency is built to do

A good agency is a specialist. It is very good at one or two disciplines (paid media, SEO, content, design, PR) and it gets better the more clearly it is briefed. Give it a defined objective, a budget and a brand to work within, and it will execute well within that channel. What it will not do, and was never set up to do, is decide whether that channel is the right place to spend the money in the first place. Agencies answer the question they’re given; they’re rarely positioned, or paid, to challenge whether it’s the right question.

What a fractional CMO is built to do

A fractional CMO sits above the channels. The job is to set the commercial priorities, decide where the budget should go and why, and hold the whole marketing effort accountable to a business outcome instead of a set of channel metrics. That includes writing the brief an agency works from, judging whether its results are actually moving the business forward, and managing the relationship when they aren’t. In a small or mid-sized business, that role rarely needs to be full-time, which is the whole point of hiring it fractionally.

  • Setting the strategy and priorities the budget follows
  • Briefing, appointing and managing agencies and freelancers
  • Owning the commercial number marketing is accountable for
  • Sitting at the leadership table as the senior marketing voice

The common mistake: hiring an agency when the missing piece is strategy

The most common misstep in small and mid-sized businesses is hiring an agency to fix a problem that isn’t really an execution problem. Nobody has decided what the business is trying to achieve, who it’s really for, or what a good return on marketing spend looks like; so the agency, quite reasonably, fills that vacuum with its own assumptions. Campaigns launch without a clear commercial target behind them. Reporting fixates on channel metrics because there’s no business metric to report against. Three months in, spend is up and nobody can say with confidence whether it worked.

That isn’t the agency failing. It’s a business asking a specialist to make decisions that belong one level up. This isn’t an argument against agencies. Plenty are excellent at what they do. It’s an argument against buying execution before you’ve decided what you’re executing towards. The fix is rarely to replace the agency; it’s to put someone in charge of the decisions above it.

When you need which, and when you need both

If your strategy is clear, your proposition is understood, and you know what success looks like, you probably just need excellent execution. Go to an agency. If you can’t say with confidence where the budget should go, what it should achieve, or which of several agencies pulling in different directions is actually right, that’s a fractional CMO gap, not a bigger media budget. Many growing businesses need both: a fractional CMO to set the direction and hold the agency to account, and the agency to do what it does well underneath that.

A quick test: if you handed an agency your annual budget tomorrow, could you tell them exactly what success needs to look like in six months? If yes, you need execution. If you’re not sure, that uncertainty is the fractional CMO’s job, not the agency’s.

Common questions

What’s the difference between a fractional CMO and a marketing agency?

A marketing agency executes within a channel (running campaigns, content or media buying against a brief). A fractional CMO sits above that: setting strategy, deciding where budget should go, and holding the whole effort accountable to a commercial outcome. Many businesses use both, with the fractional CMO briefing and managing the agency.

Can a fractional CMO manage my existing agency instead of replacing it?

Yes, and this is one of the most common ways the relationship works. A fractional CMO can take over briefing, direction and performance accountability for an agency you already have, without you needing to change supplier. It often resolves cases where an agency is performing perfectly well against a brief that was never quite right.

How do I know if I need a fractional CMO or just an agency?

If you can clearly state your strategy, audience and what success looks like, and simply need someone to execute it well, an agency is the right hire. If you’re not confident in those answers, or you have agencies producing activity without a clear commercial result, the gap is strategic, and that’s what a fractional CMO is for.

Written by

Jo van Vuuren is a fractional CMO and marketing strategist working with SMEs and startups across Brighton, London and the UK — twenty years of senior marketing leadership, brought in by the day.

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