A note on bias first. RemoteCMO does GEO work and also offers fractional CMO support to US startups. So we have an interest in two of the three answers. This guide tries to be fair to all three, including the one we do not sell.
Why this question comes up
When we asked ChatGPT whether to hire a GEO agency or a fractional CMO, it searched for both terms and answered mostly from Google's own guidance and a research paper, without naming any firm. Buyers are asking it, and the honest answer depends on your situation more than on the service.
What each option actually does
- A GEO agency (also called an AI visibility, AI SEO or AEO agency) measures how ChatGPT, Gemini, Perplexity and Google AI Overviews answer your buyers' questions, then fixes what shapes those answers: your pages, your schema, and the outside sources the engines read, such as lists, reviews and press.
- A fractional CMO is a senior marketer who acts as your head of marketing for part of the week. They own the plan, the budget split, the team and the agencies. AI search is one item on their list.
- An in-house hire is someone on your team whose job includes AI search, usually from SEO or content. They know your product well and are there every day.
Side by side
| GEO agency | Fractional CMO | In-house | |
|---|---|---|---|
| What you get | Measurement and fixes for AI answers | A senior owner for the whole marketing plan | A person on your team, every day |
| Who sets strategy | You, or your head of marketing | The fractional CMO | Whoever they report to |
| Fits when | AI visibility is a clear gap and you have an owner for it | Nobody senior owns growth, and AI search is part of a bigger plan | AI search is a core channel and the work is ongoing |
| Time to start | Fast, once scope is agreed | Fast, but needs time to learn the business | Slowest: hiring, then learning the method |
| What you need in place | Someone to approve changes and act on findings | Access to the founders and the numbers | A manager who understands the work |
| Watch for | Reports with no fixes, or no re-measure | Plans without hands to do them | One person stretched across SEO, content and AI |
How to choose, step by step
- Measure first. Run 10 real buyer questions through the engines your buyers use, per market, and log who gets named and cited. The afternoon AI visibility audit shows how. You cannot pick the right help without knowing the size of the gap.
- Ask who owns growth today. If nobody senior does, a specialist will hand findings to no one. That points to a fractional CMO, or to hiring a head of marketing.
- Ask how much of the gap is AI-specific. If you are missing from the lists, reviews and pages AI reads in each market, that is specialist work. If the problem is positioning or product, it is a CMO problem.
- Count your markets and languages. AI answers differ by country and language, so each one needs its own measurement. More markets means more ongoing work, which shifts the case toward a team or a retainer.
- Decide how long the work runs. A fixed sprint suits an agency. Ongoing work across channels suits a fractional CMO or an in-house hire.
Questions to ask before you sign
- Can you show a dated before-and-after for one market, with the same questions run twice?
- Which engines, markets and languages will you measure, and how often?
- Who does the work, and will I speak to them directly?
- What will you fix yourselves, and what will you hand to my team?
- What do you not do? A clear answer here is a good sign.
Be wary of anyone who guarantees placement in AI answers. Nobody controls what these engines say.
Combining them
The options are not exclusive. A common pattern is a fractional CMO who owns the plan, with a GEO specialist for the measuring and fixing, and an in-house hire once the work is proven. For a single market with a clear owner, a specialist alone may be enough.
Common questions
What is the difference between a GEO agency and a fractional CMO?
A GEO agency does a defined piece of work: it measures how AI engines answer your buyers and fixes the pages and sources behind those answers. A fractional CMO is a senior marketer who works part-time as your head of marketing and owns the whole plan, of which AI search is one part.
Can a fractional CMO do GEO work?
Some can, if they have done it before. Ask to see a dated before-and-after for one market. Many fractional CMOs will instead set the plan and bring in a specialist for the measuring and fixing.
When should I hire for AI search in-house?
When AI search is a core channel for you, the work is ongoing, and you have someone senior who can manage the hire. In-house teams learn your category fastest but start from zero on method, so many begin with outside help and then hire.
How do I check any of them is working?
Agree a fixed set of buyer questions per market at the start, record who gets named and cited, and re-run the same questions on a schedule. If nobody can show you a dated before-and-after, you are paying for activity, not results.