Chief AI Officer vs AI consultant vs agency: which format for your SME
Three formats, three costs, three levels of commitment. The honest comparison for an SME executive hesitating between hiring, ad-hoc subcontracting, or going through a retainer.
An SME executive who wants to move forward on AI in 2026 has three options: hire a Chief AI Officer in permanent contract, engage a consultant on a bounded mission, or contract an agency on monthly retainer. The three make sense in different situations. The objective comparison.
Option 1 - Chief AI Officer in permanent contract
You recruit a senior full-time profile, reporting to executive management, who governs AI strategy and steers execution.
Cost
Gross annual salary: 80 to 130K EUR depending on seniority and location (Paris, Lyon, regions). Loaded cost: 110 to 180K EUR. Variable bonus: 10 to 20% of fixed. Benefits (car, premium health, profit-sharing): 5 to 15K EUR. Total Year 1: 130K to 220K EUR.
Hidden costs: recruitment lead time (currently 6 to 9 months, tight market), recruitment cost (headhunter 15 to 25% of annual salary or 12 to 33K EUR), onboarding cost (3 to 6 months ramp-up before real effectiveness).
What you get
A full-time employee thinking about your business 24/7, attending every executive committee, arbitrating in real time, training your teams, and internalizing knowledge.
The risks
High HR risk. Senior AI profiles are over-solicited: average turnover of 18-24 months in France currently. If the profile leaves, you lose project memory and have to recruit again (12-18 months of loss). Misfit risk: a CAIO from large groups may not adapt to an SME.
Option 2 - AI consultant on bounded engagement
You contract a 3 to 12 month engagement with an external consultant (senior freelancer or small firm), to deploy a transformation or a specific function.
Cost
Short engagement (AI Audit): 6 to 15K EUR. Medium engagement (deployment of a function): 30 to 75K EUR. Long engagement (full transformation): 75 to 200K EUR. Generally fixed-price, not by the day, so predictable.
What you get
A concrete deliverable in a bounded timeframe: an audit, a transformed function, a deployed agent system. The relationship ends at the end of the engagement, unless extended. You recover the code, documentation, accesses.
The risks
Risk of abrupt end: when the consultant leaves, your teams must take over operations autonomously. If knowledge transfer wasn't structured, you depend on the consultant for any future evolution. Risk varies with consultant quality: the freelance AI market in France contains 99% of profiles who have never deployed an agent in production.
Option 3 - Agency on monthly retainer
You contract a monthly fixed-price with an agency that intervenes regularly on your context (equivalent to fractional Chief AI Officer).
Cost
Monthly retainer: 5 to 15K EUR depending on intervention level. Typical commitment: 6 to 12 months. Annual total: 60 to 180K EUR. For Alexis Prat's fractional Chief AI Officer formula: 10K EUR/month, 6-month commitment, or 120K EUR/year.
What you get
Continuous steering with a senior profile, without the cost and risks of a permanent hire. The relationship lasts as long as it creates value, terminable with notice. New initiatives are deployed as they come rather than batched on a bounded engagement.
The risks
Dependence risk if no knowledge transfer is planned in the contract. Dilution risk if the agency has many other clients and your file isn't a priority. Properly frame the monthly scope (deliverables, meetings, Slack access) to avoid grey zones.
Quantified comparison for an SME of 50 employees
Below, the 12-month cost and value delivered for each format, on a comparable scope (deployment of 5-10 agents in production, continuous steering, partial transfer to teams):
Permanent Chief AI Officer: 180K EUR + 15K EUR recruitment = 195K EUR, 3 months ramp-up, effective deliveries over 9 months
12-month fixed-price engagement: 150 to 200K EUR, delivery structured in phases, end of relationship at the date
Mission Core (75K) + 9 months retainer (90K): 165K EUR total, delivery + continuous steering, transfer included
Pure 12-month retainer (120K EUR): continuous steering but no big structured initial workstream
Which format to choose by situation
You haven't deployed anything yet
Start with an AI Audit (6.5K EUR, 2 weeks) to validate scope and potential ROI. Then Mission Core or Mission Phase 1 to build foundations. The permanent hire is premature: you don't yet know what profile you're looking for.
You already have a few agents, you want to accelerate
Fractional Chief AI Officer (10K/month) for continuous steering and progressive deployment. This formula covers the need of SMEs of 50 to 150 employees that want to industrialize without taking the risk of a permanent hire.
You're at 10+ agents in production, strong maturity
Time to consider a permanent hire. You know what you're looking for, you have internal teams capable of working with the profile, ROI is demonstrated. The hire becomes an investment paid back in 12-18 months.
You're over 200 employees with multiple sites
You're outside the 'real economy' SME perimeter. A classic consulting firm (Wavestone, Artefact) may be more relevant to coordinate several parallel workstreams. Or a permanent hire + annual audit firm combination.
195K EUR - Permanent hire Y1
165K EUR - Mission + retainer
120K EUR - Pure retainer
75K EUR - Mission Core only
The most expensive format isn't the one that costs the most cash. It's the one that fails. A permanent hire who leaves after 12 months = 200K lost. A poorly scoped engagement = 3 months delay. The real selection criterion is probability of success, not face cost.
Questions to ask before signing
For a permanent hire: how many agents has your future CAIO personally deployed? What's their handover strategy if you lose them at M+18?
For an engagement: is the price fixed? Who owns the delivered code? What's the team transfer structure?
For a retainer: what's the monthly scope (days, meetings, deliverables)? What's the exit notice? What's the continuity if the agency changes interlocutor?