Becoming a fractional CTO
A fractional CTO in the UK charges £800 to £1,400 a day and holds two to three clients at once. What follows is the arithmetic on that, the honest ceiling, and the cases where this seat does not work part-time at all.
What you would earn
Across 46 billable weeks rather than 52, because you will take holidays and because a year of unbroken client work is not a thing that happens.
| Day rate | 1 day a week | 2 days a week | 3 days a week |
|---|---|---|---|
| Starting out£800 a day | £36,800a year | £73,600a year | £110,400a year |
| Established£1,100 a day | £50,600a year | £101,200a year | £151,800a year |
| Top of the band£1,400 a day | £64,400a year | £128,800a year | £193,200a year |
Before tax, before your own costs, and assuming the days are actually sold. Most people starting out spend a good part of the first year at fewer days than they planned.
What moves you up the band
Higher end for regulated sectors, AI systems and technical due diligence.
How many clients the seat holds
Two to three, and two if any of them is mid-build. Technology work generates unplanned days in a way finance does not: an outage, a failed release or a security question does not wait for your scheduled Thursday.
Where the first client comes from
A non-technical founder with an agency or a junior team and no way to judge the work. That is the clearest version of the problem this seat solves, and they usually find you through somebody who has already worked with you.
What the work actually is
Deciding what gets built and, more consequentially, what does not. Also judging engineers, which a non-technical founder cannot do and will pay real money to have done properly.
When this seat does not work fractionally
- You would be the only engineer. That is a contract development job at a fractional price.
- The company needs daily technical firefighting rather than technical direction.
- They want a technical co-founder, which is equity and commitment rather than a day rate.
What people get wrong
- Writing the code. The moment you become the delivery capacity, the seat collapses into contracting.
- Taking on a rescue with no authority to change the team or the architecture.
- Underpricing because the company is early. Early companies are harder, not easier.
The mechanics, briefly
Most UK fractional executives work through their own limited company and invoice per day or on a monthly retainer. Professional indemnity cover is worth having before the first engagement rather than after. Check what your last employment contract says about notice and restrictions before you start approaching anybody, particularly if a first client might be somebody you met there.
Employment status is the question that worries people most, and it is worth understanding properly rather than assuming: IR35 and fractional executives covers who decides, what gets tested, and the directorship point that catches people out.
Common questions
What should I charge as a fractional CTO in the UK?
£800 to £1,400 a day is the band on the bench, with a typical rate around £1,100. Higher end for regulated sectors, AI systems and technical due diligence. At £1,100 a day, two days a week is about £101,200 a year across 46 billable weeks.
How many clients can a fractional CTO hold at once?
Two to three, and two if any of them is mid-build. Technology work generates unplanned days in a way finance does not: an outage, a failed release or a security question does not wait for your scheduled Thursday.
Where does the first client actually come from?
A non-technical founder with an agency or a junior team and no way to judge the work. That is the clearest version of the problem this seat solves, and they usually find you through somebody who has already worked with you.
When does a fractional CTO arrangement not work?
You would be the only engineer. That is a contract development job at a fractional price. The company needs daily technical firefighting rather than technical direction. They want a technical co-founder, which is equity and commitment rather than a day rate.
Other seats
Hiring one rather than becoming one? What a fractional CTO covers and what one costs are the other side of the same numbers.
Listing is free and always will be
No subscription, no commission, and nothing taken from your rate. What listing costs, here and elsewhere, or put yourself on the bench.