Fractional CTO or interim CTO: two jobs that share a title
One is a day or two a week for as long as it's useful. The other is a full-time seat with an end date. Which you need depends on whether the chair is empty or the decisions are.
There are six names for what looks like one job: fractional CTO, interim CTO, part-time CTO, virtual CTO, outsourced CTO, CTO as a service. Five of them are the same thing. One is a different job, and hiring it by mistake costs you months.
Five names, one arrangement
Fractional, part-time, virtual, outsourced and “as a service” all describe the same deal. A senior person owns your technology decisions for a slice of the week, and either side can end it with notice. (Outsourced is the odd label of the five, since it sounds as though the work leaves the building, and it doesn’t.) The label tells you who wrote the website. Compare what they’ve run and what they’ve built.
Interim is the odd one out
An interim CTO takes the seat full-time, for a fixed period measured in months, and manages the team day to day until a permanent hire arrives or an event completes. It’s line management as much as technology: the one to ones, the hiring pipeline, and whoever rings at eleven at night.
Your CTO has resigned, or you’re mid-sale and the buyer wants a named technical lead through completion. The seat is empty, and a day a week won’t fill it.
How to tell which you need
Are decisions missing, or is a manager missing?
If the team is functioning and what’s absent is direction (what to build next, whether the agency’s quote is sane), you need a fractional CTO. A day or two a week is enough, since other people take longer to carry out a decision than the right person takes to make it.
If eight engineers have no line manager and releases are slipping because nobody is chasing them, you need an interim.
| Fractional CTO | Interim CTO | |
|---|---|---|
| Time | A day or two a week | Full-time |
| Length | Open-ended, ends on notice | Fixed, ends on a date or an event |
| Fills | A gap in decisions | An empty seat |
| Manages the team daily | No | Yes |
| Right when | The team works and the direction doesn’t | The team has nobody to answer to |
Past thirty or so engineers the two jobs start to overlap, and I’d want to see the org chart before saying which.
Where people go wrong
It goes wrong one way more than the other. A founder loses a CTO, feels the hole, and hires a fractional one because the monthly figure is smaller. Three months later the team is still drifting, because what it lacked was somebody present on a Tuesday morning.
The reverse happens too. A business with four developers and no technical leadership hires a full-time interim, and finds there were about two days of CTO work in the week.
The price follows the number of days. If you’re weighing the two on cost, read what a fractional CTO costs in the UK, then ask how many days of senior attention your situation can use.
What I do, and what I don’t
I work fractionally, a day or two a week on retainer, and I’m reachable for a decision in between.
I don’t take interim roles. A full-time seat somewhere else is a promise I couldn’t keep alongside my own company, and an interim who can only give you part of the week is worse than no interim at all, because the team still has nobody to answer to and the budget has gone anyway.