In January 2025 I did something most founders never do voluntarily: I handed the CEO seat of my own company to someone else. I recruited my own successor at Operio Group and managed the transition, and the process taught me something I hadn't fully understood in fifteen years of running businesses, which is what the CEO seat actually is. It isn't a person, and it isn't a title. It's a set of obligations: the operating cadence, the leadership team, the numbers, and the accountability for all three. Once you see the job that way, the difference between a fractional CEO and an interim CEO stops being confusing, because the question is simply how much of the seat you're buying, and for how long.

I raise this because the two terms get used almost interchangeably, usually by people selling one or the other. They are not the same thing. They solve different problems, they cost different amounts in different ways, and hiring the wrong one is worse than hiring neither. So here is the distinction as an operator sees it, rather than as a staffing or headhunting firm's website describes it.

What a fractional CEO actually is

A fractional CEO is part-time chief executive leadership on an ongoing retainer, typically one to two days a week. The important word is not "fractional." It's "CEO." This is not a consultant who writes you a strategy document and leaves, and it's not an advisor who takes your call once a month. A real fractional CEO owns things: the weekly operating rhythm, the leadership team's performance, the P&L review. They sit alongside an owner, a founder, or a leadership team that stays in place and keeps doing what only they can do, while the fractional executive runs the machinery of the business that the owner either can't run or shouldn't be running.

The arrangement works because most businesses under a certain size don't have five days a week of genuine CEO work. They have one or two days of it, done badly or not at all, spread thinly across a founder who is also the head of sales, the chief engineer, and the person who unlocks the building. Buying those one or two days properly is the whole idea.

What an interim CEO actually is

An interim CEO is the seat itself. Full-time, full authority, for a defined period with a defined end. You hire one when the seat is empty or about to be: a departure, a serious illness, a death in an owner-run business, a family dispute that has left the company leaderless, a turnaround, or the run-up to a sale. The interim's job is to stabilise the business, run it properly, and then hand it over to a permanent successor. An interim engagement that doesn't end in a clean succession has failed, whatever the numbers say, and I hold that view with some conviction because I've run the play from the other side. When I recruited my own replacement at Operio, the handover was the product. Everything else was preparation.

The three differences that actually matter

Strip away the marketing language and the two roles differ on three axes.

Time. Fractional is one or two days a week, indefinitely or until the business grows into a full-time hire. Interim is five days a week (in practice, more) for six to eighteen months.

Authority. A fractional CEO shares the room with an owner who retains final say on the things owners should retain, and the mandate has to spell out where one ends and the other begins. An interim CEO holds the whole seat. If the board isn't prepared to give an interim genuine authority over the team and the spending, they shouldn't hire one, because a CEO who has to phone home before acting is just an expensive observer.

The ending. Fractional engagements evolve. They shrink, grow, or convert as the business changes. Interim engagements end, on purpose, in a succession that was being planned from the first week. If a candidate for an interim role can't describe how their last engagement ended and who they handed it to, that tells you most of what you need to know.

When each one fits

Fractional fits a business whose ownership and day-to-day leadership no longer line up. Sometimes that's the founder who is still the right leader but has run out of bandwidth: the company is sound, the team is decent, and the constraint is that everything still routes through one person who is now the bottleneck. Just as often it's an owner who was never the operator at all: the family that holds the business but no longer works in it, or a private equity firm that has bought a company too small to carry a full-time chief executive's compensation package but too important to be left running itself. Either way, the business needs one or two days a week of genuine CEO work that nobody currently in the building is positioned to do.

Interim fits an empty seat, or one that needs to be emptied. A resignation with no succession plan. The death or serious illness of an owner-manager, leaving a family with a business none of them can run, or wants to run. A falling-out between family owners that has left the company without anyone clearly in charge. A business that needs eighteen months of hard, unpopular decisions that a permanent hire shouldn't have to carry as their opening act. An owner preparing for a sale who needs the business to run demonstrably without them, because a business that can't is worth materially less to a buyer.

When neither fits

Sometimes the honest answer is neither.

If your business needs sustained, full-time leadership for the foreseeable future and can afford it, hire a permanent CEO. Fractional and interim executives are bridges, and a bridge is the wrong purchase when what you need is a building. Equally often, the problem isn't the CEO seat at all. A founder or owner who is drowning in operations but still the right person to lead the company usually needs a strong COO or a general manager, not a part-time replacement for themselves. And if the real issue is that the owner won't delegate to anyone, no external hire of any description will fix that. The pattern will simply repeat with a more expensive cast.

How the costs are structured

The figures vary with the size of the business and the days committed, but the structures are worth understanding. A fractional CEO is a monthly retainer scaled to the days per week, with no employment obligation, no equity expectation as a default, and notice periods measured in weeks. An interim CEO is closer to a full compensation package compressed into the engagement period, sometimes with a completion element tied to the handover. The comparison to make is not fractional versus interim, since they solve different problems. It's each of them against the fully loaded cost of a permanent hire: base, bonus, equity, benefits, the recruiter's fee, and the six months of runway it takes to know whether you chose well.

Questions to ask before you hire either

Whichever way you lean, ask these before anyone signs anything. Have you run a business of this size and shape, with a real P&L, not an advisory relationship? Have you ever handed a business over, and can I speak to the person you handed it to? What authority do you need in writing, and what happens when we disagree? How will we both know it's working by day ninety? And how does this end?

Good candidates answer those questions with specifics and without flinching. I've written a fuller set of them, with the answers a good candidate should give, in What to Ask an Interim CEO Before You Hand Them the Keys.

Where I've landed

Having sat in the founding seat, the CEO seat, and now the board seat of the same company, my view is that the fractional and interim models exist because the alternative for most mid-market businesses is worse: an owner running past their limits, or an empty chair filled in a panic. Bought deliberately, with a clear mandate and a planned ending, either one can be the best money the business spends that year. Bought vaguely, they're an expensive way to postpone a decision.

If you're weighing this up for your own business and want to talk it through with someone who has been on both sides of the desk, my door is open — the details are on my leadership and consulting page.