Choose by who needs to own the strategy. A fractional CMO owns the plan and the decisions but needs execution capacity underneath. An agency owns execution inside its channels. A full-time hire owns everything and is the slowest and most expensive to start. Match the model to the gap you actually have.

What each model owns, and who is accountable

The useful question is not which one is better. It is which layer of your marketing is currently unowned. An agency owns execution inside the channels it is hired for: it buys media, ships creative, and reports on what it ran. A fractional CMO owns the layer above that, meaning the plan, the budget allocation across channels, the measurement standard everyone reports against, and the decision about what stops. A full-time hire owns both layers once they are hired and ramped. Most brands investing seriously in paid media already have execution. What they lack is somebody senior who reconciles the channels to each other and to the bank account. If that describes you, adding more execution will not fix it.

Speed and management time follow from the same split. An agency or a fractional CMO can be working inside weeks, because both arrive with a method. A full-time search runs on a hiring timeline, and the ramp continues past the start date. An agency also needs somebody to direct it, which is your time. A fractional CMO is the person doing the directing.

Across six months with an athletic apparel brand, we chose to scale rather than squeeze efficiency. Sales rose 35.7% year to date to $9.27M, paid media investment rose 42% year over year, and blended ROAS held at 3.36x. That was measured on blended ROAS, not platform-reported ROAS.

How each model behaves when something goes wrong

Models look similar in a good quarter. They separate when performance drops. Agency reporting is scoped to what the agency runs, so a drop inside its channel gets investigated inside that channel. That is reasonable, and it is incomplete if the cause sits in site speed, an email flow that stopped sending, or a tracking change that made the numbers look worse than the business actually is. A fractional CMO is accountable for the read across all of it, including the parts no vendor is paid to watch. That breadth is the argument for the fractional CMO model, and it shows up most clearly in a bad quarter. A full-time hire has the same breadth in theory, though a first marketing leader is often learning the account while diagnosing it.

Where the fractional model is the wrong choice

Three situations. If paid media spend is small, a fixed fee for senior strategy consumes budget that would do more work as media, and the decisions at that stage are simpler than the model is built for. If you have no execution capacity, internal or partner, a fractional CMO produces a good plan that nobody runs, which is worse than no plan because it costs money and creates the feeling of progress. And if what you need is somebody hands on keyboard in the ad account every day, building audiences, writing briefs, pulling reports, hire that person or that agency instead. A fractional CMO doing daily execution is paid senior rates for work that is not senior, and the strategic layer goes unattended anyway.

Start by naming the gap. If nobody owns the number that spans every channel, that is a strategy gap and more execution will not close it. If the plan exists and nothing ships, that is an execution gap. A free thirty minute growth audit from Plaid Testing will tell you which gap you actually have. It covers tracking, account structure, and three fixes you can hand to whoever runs your media today.