Becoming a Part-Time CTO
A part-time CTO sells technical judgement by the day rather than code by the hour. Companies buy it when they have engineers but no one to decide, or when they are about to spend serious money on something they cannot evaluate. It requires no capital and no staff, and the constraint is credibility: clients are buying your track record, so you need one.
Who this is for
Ideal candidate: an experienced engineer, technical lead or former CTO. This is not an entry-level business. Startup capital: almost none. A website, an invoice and professional insurance. Time to first revenue: weeks, if you already have a network. Months if you are starting cold. Licence needed: no. Can one person run it? Yes, that is the whole model. In person? Mostly not. Occasional on-site days help, but the work is largely remote.
What companies are actually buying
They are not buying code. If they needed code they would hire a developer, and a cheaper one.
They are buying the ability to decide, and to be held responsible for deciding. Three situations produce almost all the demand.
A company with engineers and no one to lead them. Common in businesses where the founder is commercial. The team is capable and pulling in different directions, and nobody senior enough is arbitrating.
A company about to spend money it cannot evaluate. A quote from an agency, a rebuild, a platform migration, a vendor contract. They need someone who can say whether the number is sane, and whose opinion carries weight because they have done it before.
A company after something went wrong. A failed project, a security incident, a departed lead developer. The immediate need is stabilisation and an honest account of what state things are in.
The second and third convert fastest, because there is a deadline attached and the cost of getting it wrong is obvious.
How engagements are structured
Retained days per month. The standard model: a fixed number of days at a fixed rate, billed monthly. Predictable for both sides and easy to renew, which is what you want.
Fixed-scope reviews. A technical audit, a due diligence exercise, a build-or-buy assessment, delivered as a document with a recommendation. Excellent as a first engagement because it is bounded, and it very often leads into a retainer.
Interim leadership. Full-time or near it for a defined period, usually covering a departure or a specific project. Pays best, occupies the most capacity, and ends.
The pattern that works is to lead with a fixed-scope review, because a company that will not commit to a retainer with someone they have never worked with will happily pay for a two-week assessment. Once the assessment lands, the retainer is an easy conversation.
What to charge
Day rates vary enormously by country, by sector and by how senior the buyer perceives you to be, so any single figure quoted online is likely wrong for you. Two things are more useful than a number.
Price against what the alternative costs. A full-time CTO is a salary plus payroll costs, recruitment, equipment and equity, and it comes with a notice period. Four days a month against that comparison is cheap, and framing it that way is more persuasive than any hourly justification. The fractional CTO cost calculator does that comparison.
Never quote hourly. Hourly invites scrutiny of your time rather than your judgement, and it punishes you for being fast, which after twenty years is the entire value you are selling. Day rates or monthly retainers only.
Raise the rate when you are booked. It is the only lever you have, because you cannot add capacity without becoming an agency, which is a different business with different problems.
Getting the first client
Almost all early fractional work comes from three places.
People who have worked with you. Former colleagues, former managers, former clients. They already know what you can do, which removes the only real obstacle. Tell them specifically what you are now doing, because they will not infer it.
Investors and accelerators. They see portfolio companies with exactly this problem and are asked for recommendations constantly. One relationship here can supply work for years.
Agencies and consultancies. They routinely meet clients whose problem is not theirs to solve, and they would rather refer than say no.
What does not work early: cold outreach at volume, and content marketing before you have a track record to point at. Both work later, and neither will produce your first client.
What makes it hard
Feast and famine. Two retainers is comfortable, one is precarious, three is over capacity. Managing that cycle is the actual skill, and it argues for always having a fixed-scope review in the pipeline.
Being asked to do the work. Clients drift from wanting decisions to wanting delivery, because it is cheaper than hiring. Decide in advance whether you do that and price it separately.
Responsibility without authority. You will be asked to fix outcomes you do not control. Being explicit at the start about what you decide and what you advise on prevents most of it.
Isolation. No team, no colleagues, and every decision reviewed by nobody. Most people who last at this build a small group of peers to think out loud with.
Free: the Fit Checklist
A short checklist for deciding whether an idea fits you before you spend anything on it. It arrives by email and subscribes you to the free Sunday edition.
FAQ
What is a fractional CTO? An experienced technical leader who works with a company part-time, usually a set number of days a month, providing technical judgement and leadership rather than hands-on development.
How much does a fractional CTO charge? Rates vary widely by country, sector and seniority, so treat published figures with caution. Charge by the day or on a monthly retainer, and price against what a full-time hire costs including payroll, recruitment and equity, not against an hourly rate.
Do you need to be a former CTO? Not necessarily, but you need a track record clients can verify: senior engineering leadership, delivery of comparable systems, or specific expertise in their domain. Credibility is the whole product.
How do you find your first fractional CTO client? Through people who have worked with you, through investors and accelerators who are asked for recommendations, and through agencies that meet clients they cannot help. Cold outreach rarely produces the first one.
Is it better than contracting? It pays better per day and is more interesting, because you decide rather than execute. It is also less stable, since retainers end and pipelines are lumpy.
Can you do it alongside a job? A fixed-scope review can be, an interim role cannot, and a retainer depends on the days involved and on your employment contract. Check the contract before agreeing anything.
Free: the Fit Checklist
A short checklist for deciding whether an idea fits you before you spend anything on it. It arrives by email and subscribes you to the free Sunday edition.
