How Much Should You Budget for a Fractional CTO in the UK? (2025 Complete Breakdown)

You know you need technical leadership, but you've no idea what to budget.

£3,000 per month? £10,000? What if you're overpaying? What if you underspend and get junior talent? And how do you justify this cost to your board when they're already questioning why you can't just "hire another developer"?

Most UK businesses between £1-10M revenue face exactly this problem. You need a fractional CTO but the pricing seems to vary wildly depending on who you ask.

I've worked with 15+ UK businesses navigating fractional CTO engagements. This is what you'll actually pay in 2025, what determines where you fall in the range, and how to budget properly without wasting money.

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The Direct Answer: UK Fractional CTO Budget by Business Stage

UK businesses budget £3,000-10,000/month for fractional CTO services depending on time commitment (2-5 days/month), experience level, and business complexity. Most UK SMBs at the £1-10M revenue stage pay £4,500-7,000/month for 3 days per month.

Quick Budget Guide by Stage:

• Pre-revenue to £1M: £3,000-4,500/month (2 days/month)
• £1M-£5M revenue: £4,500-7,000/month (3 days/month)
• £5M-£10M revenue: £7,000-10,000/month (4-5 days/month)
• £10M+ revenue: £10,000-15,000/month (high-end fractional) or transition to full-time

But that's just the base retainer. There are hidden costs most businesses miss, factors that push you to the upper or lower end of each range, and important decisions about what's included versus what costs extra.

This guide covers everything you need to budget accurately and avoid expensive surprises.

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Understanding Fractional CTO Pricing Models

UK fractional CTOs use three main pricing models. Understanding each helps you budget properly and negotiate effectively.

Monthly Retainer (Most Common)

Range: £3,000-10,000/month

What you typically get:

• £3,000-5,000/month: Startups, 2-3 days per month, strategic guidance and architectural oversight
• £5,000-7,500/month: Scale-ups, 3-5 days per month, active team management and vendor oversight
• £7,500-10,000+/month: Established SMBs, 5-10 days per month, near full-time engagement

What's included in a standard retainer:

• Fixed monthly hours (16-40 hours depending on tier)
• Regular check-ins (weekly or fortnightly meetings)
• Strategic planning and roadmap development
• Architecture decisions and technical reviews
• Email/Slack support between scheduled sessions
• Documentation and board-level reports

What's typically NOT included:

• Hands-on coding (they review code, don't write production code)
• 24/7 emergency support
• Hours beyond the monthly allocation
• Extensive travel (if requiring in-person days)
• Recruitment fees for hires they help make

Why retainers make sense: Most fractional CTOs prefer retainers because they align incentives properly. You're paying for outcomes and strategic guidance, not hours. They can solve problems efficiently without worrying about billing time.

Day Rate Model

Range: £800-1,250/day

Typical engagement: 2-4 days per month

Monthly cost: £1,600-5,000

When this makes sense:

• Project-based work with clear deliverables
• Trial engagement before committing to retainer
• Temporary coverage whilst recruiting full-time
• Specific initiatives (architecture review, due diligence)

A Birmingham company used day rates for a 6-week architecture review (8 days total at £1,000/day = £8,000). After seeing the value, they moved to a £6,000/month retainer for ongoing support.

Hourly Rate (Less Common)

Range: £150-400/hour depending on experience

• £150-200/hour: Mid-level, 5-10 years CTO experience
• £200-300/hour: Senior, 10-15 years experience
• £300-400+/hour: Highly specialised (AI, FinTech, etc.)

When you'll encounter hourly pricing: Ad-hoc consulting, short-term advice, or initial assessment calls. Most fractional CTOs push for retainers or day rates because hourly creates perverse incentives (billing for time vs solving problems).

Budget consideration: If someone quotes hourly for ongoing work, factor in that 40 hours/month at £200/hour = £8,000/month. You might get better value with a £6,000 retainer that includes strategic thinking time they won't bill hourly.

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Budget by Your Business Stage (Detailed Breakdown)

Your business stage determines how much fractional CTO support you need, which directly affects your budget.

Pre-Revenue to £1M Revenue

Recommended budget: £3,000-4,500/month

Time commitment: 2 days per month (16 hours)

What you get at this level:

• Strategic technology direction and roadmap
• Architecture decisions for MVP/early product
• Vendor evaluation (cloud hosting, SaaS tools)
• Technical hiring support (1-2 hires per year)
• Monthly check-ins plus ad-hoc questions via email/Slack
• Investor/board communication support

What you don't get: Day-to-day team management, hands-on implementation, daily availability. At this stage, you're getting strategic guidance to avoid expensive mistakes, not full-time tactical leadership.

Real example: A London FinTech startup (pre-revenue, raising seed) paid £3,500/month for 2 days. The fractional CTO defined their architecture, helped hire their first two developers (avoiding one bad hire worth £75,000), and prepared technical due diligence for their seed round. Total cost: £21,000 for 6 months. Value: Closed £500,000 seed round, avoided £75,000 bad hire, built on solid technical foundation.

ROI at this stage: Primarily mistake prevention. One avoided architectural mistake (£80,000-200,000 to fix later) justifies the entire annual cost.

£1M-£5M Revenue

Recommended budget: £4,500-7,000/month

Time commitment: 3 days per month (24 hours)

What changes at this level:

• More active involvement in team decisions
• Regular 1-on-1s with technical team leads
• Vendor contract negotiations (saving £20,000-50,000/year)
• Scaling architecture decisions (preparing for 5x growth)
• Process improvements (CI/CD, code review, testing)
• Weekly or fortnightly check-ins

Team size: Usually 3-8 developers at this stage. The fractional CTO provides direction and oversight without needing to manage day-to-day.

Real example: A Manchester e-commerce business (£3M revenue, 6 developers) paid £5,500/month for 3 days. The fractional CTO renegotiated their AWS contract (saving £32,000/year), prevented a platform migration that would have cost £120,000, and improved deployment speed by 60%. Total cost: £66,000/year. Measurable savings: £152,000 in Year 1.

When to increase to 4 days: If you're hiring 2+ developers per quarter, making major technical decisions monthly, or managing complex vendor relationships.

£5M-£10M Revenue

Recommended budget: £7,000-10,000/month

Time commitment: 4-5 days per month (32-40 hours)

Near full-time engagement at this level:

• Weekly involvement with technical team
• Active participation in strategic decisions
• Board-level technology reporting
• Managing 10-15 person technical teams
• Vendor and partner relationship management
• Security and compliance oversight
• M&A technical due diligence (if acquiring)

Decision point: At this stage, you're approaching the threshold where full-time makes sense. The question becomes: do you need 5 days/month (fractional) or 20 days/month (full-time)?

Real example: A Bristol SaaS company (£7M revenue, 12 developers) paid £8,500/month for 4 days. After 18 months, they converted the fractional CTO to full-time as they scaled to £15M. The fractional period saved £140,000 compared to hiring full-time immediately, whilst getting the strategic leadership they needed.

When to transition to full-time: When you need daily hands-on management, have 15+ developers, or technical decisions need to be made daily rather than weekly.

£10M+ Revenue

Budget options:

• High-end fractional: £10,000-15,000/month (5-8 days)
• Full-time CTO: £15,000-20,000/month all-in (£180,000-240,000 salary + costs)

At this scale, full-time usually makes more sense unless:

• You have a strong Tech Lead managing day-to-day operations
• Your business is services (not product), so technology is support function
• You're in holding pattern before major growth phase
• You're using fractional whilst recruiting full-time

A Leeds company at £12M revenue maintained fractional (£11,000/month) because they had an excellent VP Engineering handling day-to-day, and just needed strategic CTO guidance. This saved them £120,000/year versus full-time.

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Five Factors That Determine Where You Fall in the Range

Two businesses at the same revenue can pay very different amounts. Here's why.

Factor 1: Time Commitment Required

The biggest factor. More days per month = higher cost.

Cost per day breakdown:

• 2 days/month: £3,000-4,500 (£1,500-2,250/day effective rate)
• 3 days/month: £4,500-7,000 (£1,500-2,333/day)
• 4 days/month: £7,000-9,000 (£1,750-2,250/day)
• 5 days/month: £9,000-12,000 (£1,800-2,400/day)

Notice the effective day rate increases slightly with more days, because higher commitment = more value and flexibility needed.

How to determine days needed: Count major technical decisions per month + team size consideration. 1-2 major decisions + team under 5 people = 2 days. 3-5 decisions + 5-10 people = 3 days. Complex architecture + 10+ people = 4-5 days.

Factor 2: CTO Experience Level

Junior fractional CTO (5-10 years CTO experience):

• Lower end of each range
• Good for straightforward technical situations
• May lack experience with scale or complex situations
• Budget: £3,000-6,000/month typical

Senior fractional CTO (10-15 years experience):

• Mid to upper range
• Handled multiple scaling situations
• Cross-industry experience
• Budget: £5,000-9,000/month typical

Specialised/niche (AI, FinTech, HealthTech, etc.):

• Upper end of range, sometimes premium above
• Deep expertise in regulated or complex domains
• Specific technical knowledge (AI/ML, blockchain, etc.)
• Budget: £8,000-15,000/month possible

Budget tip: Don't just hire the cheapest. A senior CTO preventing one £100,000 mistake justifies the higher rate immediately.

Factor 3: Business Complexity

Simple tech stack = lower cost:

• Standard web application
• Well-known technologies (React, Node, AWS)
• Small team (under 5 people)
• No complex integrations
• Budget: Lower end of range for your stage

Complex/regulated = higher cost:

• FinTech, HealthTech (regulatory requirements)
• Complex data pipelines or AI/ML
• Multiple system integrations
• Large team (10+ developers)
• Budget: Upper end of range, possibly premium

A London HealthTech company (£4M revenue) paid £8,000/month (upper end) because they needed someone who understood MHRA regulations, clinical data handling, and complex compliance requirements. The regulatory expertise justified the premium.

Factor 4: Engagement Type

Strategic only (lower cost):

• High-level guidance and decision-making
• Monthly check-ins and architecture reviews
• No hands-on involvement
• Works for businesses with strong Tech Lead

Strategic + hands-on (higher cost):

• Code reviews and technical assessments
• Active vendor negotiations
• Hands-on team mentoring
• More time intensive

Remote vs in-person:

• Fully remote: Standard rates
• Monthly in-person (London/regional): Add £500-1,000/month for travel
• Weekly in-person: Add £2,000-3,000/month or expect premium rates

Factor 5: Geographic Location

London rates: 15-20% higher than regional UK

• £5,000/month regional might be £5,750-6,000/month London
• Higher cost of living, higher demand
• More experienced CTOs in London market

Regional UK rates: Manchester, Birmingham, Bristol, Leeds, Edinburgh

• Standard rates as outlined in this guide
• Growing tech scenes, competitive pricing

Remote-first: Geography matters less

• Many fractional CTOs work fully remote
• You can access UK-wide talent at regional rates
• Occasional in-person can be managed with travel

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Hidden Costs Most Businesses Miss

The monthly retainer isn't your only cost. Budget for these or face surprises.

Hidden Cost 1: Onboarding Time Investment

The reality: First 2-4 weeks are learning curve. They're productive but not at full effectiveness yet.

Your time investment:

• Initial briefing: 3-4 hours (your time + key team members)
• System access and setup: 2-3 hours (IT/admin time)
• Weekly check-ins ramping up: 2-3 hours/week

Budget impact: Factor in 10-15 hours of your team's time in Month 1. At £100/hour average fully-loaded cost, that's £1,000-1,500 hidden cost.

How to minimize: Have documentation ready (tech stack, team structure, current challenges), give broad system access quickly, schedule intensive onboarding first week.

Hidden Cost 2: Tool and Software Access

What they'll need access to:

• Code repository (GitHub/GitLab): £15-30/month additional seat
• Project management (Jira/Linear): £10-20/month
• Communication (Slack Pro): £6-12/month
• Cloud infrastructure (AWS/Azure read access): Often free
• Documentation (Notion/Confluence): £8-15/month

Total: £50-100/month in additional software costs

Seems small, but over 12 months that's £600-1,200 you need to budget.

Hidden Cost 3: Travel Expenses (If Applicable)

If you're requiring in-person days:

• Regional travel (Manchester to Birmingham): £150-250/day (train + meals)
• London travel from regional: £250-400/day (train + London expenses + time)
• Monthly in-person requirement: £500-1,000/month added cost

How to handle in contracts:

• Clarify who pays travel (usually client)
• Set reasonable limits (e.g., standard class rail, modest meals)
• Consider if in-person is actually needed (most work remote fine)

A Bristol company initially required monthly in-person, adding £800/month. After 3 months they realized remote worked fine and dropped this requirement, saving £9,600/year.

Hidden Cost 4: Overage Charges

What happens when you need more time than retainer includes?

Most contracts specify overage rates: typically 1.25-1.5x the standard hourly equivalent.

Example: £6,000/month retainer for 3 days (24 hours) = £250/hour effective rate. Overage might be £315-375/hour.

When overages happen:

• Urgent technical crisis requiring extra time
• Major hiring push (interviewing 5+ candidates)
• Significant unexpected project (vendor evaluation, due diligence)
• Scope creep from initial agreement

Budget for overages: Add 10-15% buffer for occasional extra hours. If your retainer is £6,000/month, budget £6,600-6,900 for months when overages happen.

How to avoid surprise overages: Clear scope definition upfront, regular communication about hours used, flag when approaching limit, renegotiate retainer if regularly exceeding.

Hidden Cost 5: Knowledge Transfer and Documentation

If transitioning from or to a fractional CTO:

• Transitioning TO fractional (from previous CTO): 5-10 hours of their time understanding previous decisions
• Transitioning FROM fractional (to full-time hire): 10-20 hours of handover and documentation

Cost: Transitions are either included in first/last month or billed separately at £2,000-5,000 for comprehensive handover.

Budget tip: Clarify transition expectations in initial contract. Good fractional CTOs document as they go, making handover easier.

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What's Included vs What Costs Extra

Understanding what's standard versus what's additional helps you budget accurately and avoid scope disputes.

Standard in Most Retainers

Strategic and planning activities:

• Technology strategy and roadmap development
• Architecture decisions and technical reviews
• Vendor evaluation and recommendations
• Build vs buy decisions
• Technical risk assessment
• Security and compliance guidance

Team and hiring:

• Technical interview support (assess candidates)
• Job specification creation
• Offer guidance and salary recommendations
• Team structure recommendations
• Mentoring and coaching tech leads

Communication and reporting:

• Regular check-in meetings (weekly/fortnightly)
• Email/Slack support between sessions
• Monthly or quarterly reports
• Board presentation support
• Investor technical due diligence support

Typically Costs Extra

Hands-on implementation work:

• Writing production code
• DevOps implementation (they design, someone else implements)
• Database optimization work
• Security implementation (vs guidance)

Recruitment services:

• Full recruitment process management (they support, not run it)
• Sourcing candidates (vs assessing your candidates)
• Recruitment agency fees (if hiring through their network)

Extended availability:

• Emergency/weekend support (unless negotiated)
• Hours beyond monthly retainer
• On-call availability

Training and workshops:

• Full-day workshops for teams
• Formal training delivery
• Conference speaking on your behalf

Extensive travel:

• International travel
• Multi-day on-site requirements
• Multiple offices/locations

Contract Red Flags

Watch out for contracts with:

• Vague scope ("general CTO services")
• Unlimited scope promises ("whatever you need")
• No clear hour allocation
• No defined deliverables first 90 days
• Unclear overage policy
• Auto-renewal without review points

A Manchester company signed a vague contract and ended up in disputes about what was "included." After 6 months and £48,000 spent, they renegotiated with clear scope and saved ongoing disputes.

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How to Justify This Investment to Your Board

You're convinced, but your board is questioning £72,000/year for "part-time" support. Here's how to build the business case.

Framework 1: Cost Avoidance

The business case:

• Average cost of major technical mistake: £80,000-200,000
• Probability of mistake without CTO guidance: 40-60%
• Expected cost without CTO: £32,000-120,000
• Fractional CTO investment: £60,000-72,000/year
• Net benefit: £0-£60,000 (break-even to positive)

Present it as insurance: "We're spending £60,000 to avoid £100,000+ mistakes. That's a 67% discount on potential losses, not a cost."

Framework 2: Comparison to Alternatives

Full-time CTO cost breakdown:

• Salary: £150,000
• Employer NI (13.8%): £20,700
• Pension (5%): £7,500
• Bonus (15%): £22,500
• Benefits: £5,000
• Recruitment: £30,000-45,000 (one-off)
• Year 1 total: £235,700-250,700
• Year 2+ annual: £205,700

Fractional CTO cost:

• Monthly retainer: £6,000
• Tools/access: £75
• Occasional overages: £300
• Annual total: £76,500

Savings: £129,200 in Year 1, £129,200/year ongoing

Present to board: "We get 70% of the value at 38% of the cost. When we hit £8-10M revenue and need full-time, we'll have saved £260,000 over two years whilst building on solid foundations."

Framework 3: ROI Timeline

Month 1-3: Quick wins

• Technology audit identifies £30,000/year waste
• Prevents one bad architectural decision (£80,000 value)
• Value delivered: £110,000

Month 4-6: Strategic improvements

• Vendor renegotiation saves £25,000/year
• Process improvements increase velocity 30%
• Value: £40,000 direct + velocity benefits

Month 7-12: Compound benefits

• Better hiring decisions (avoided 1 bad hire = £75,000)
• Ongoing cost optimizations
• Faster feature delivery enabling revenue

Total Year 1 value: £225,000-275,000

Total Year 1 investment: £72,000

ROI: 213-282%

Break-even typically occurs in 3-6 months. After that, it's pure positive return.

One-Page Executive Summary Template

Use this structure for your board paper:

FRACTIONAL CTO BUDGET PROPOSAL

Recommendation: Engage fractional CTO at £6,000/month

Annual Investment: £76,500 (retainer + tools + occasional overages)

Expected Year 1 Return: £150,000-225,000 through cost avoidance, optimization, and better decisions

Break-even: 3-6 months

Alternative: Full-time CTO costs £235,000 Year 1, saving of £158,500 with fractional

Risk Mitigation: 3-month trial with 30-day notice period

Decision Required: Approve budget and begin search

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Budget Warning Signs: Over and Under-Budgeting

Red Flags You're Under-Budgeting

Paying under £3,000/month:

• You're getting junior talent or insufficient time
• 2 days/month from experienced CTO is minimum for strategic value
• Less than this is ad-hoc consulting, not fractional CTO

Expecting full-time availability on part-time budget:

• £4,000/month gets you 2-3 days, not 5 days
• Expecting daily responses and constant availability
• Scope creep without budget adjustment

Not factoring in hidden costs:

• Tools, travel, overages add 10-20% to base retainer
• Budgeting £6,000 when real cost is £7,000
• Surprised by additional charges

Comparing to developer day rates:

• "A developer costs £400/day, why is CTO £1,500/day?"
• Wrong comparison - CTO provides strategic value, prevents expensive mistakes
• One prevented £100,000 mistake justifies the premium

Red Flags You're Over-Budgeting

Paying over £12,000/month for fractional:

• At this cost, you're approaching full-time territory
• Unless highly specialized need, you should hire full-time
• Exception: Using fractional whilst recruiting full-time

Paying for services you don't need:

• 5 days/month when you only need 3 days
• Premium specialized expertise you're not using
• In-person requirements that could be remote

Not negotiating based on commitment length:

• 12-month commitments often get 10-15% discount
• Paying month-to-month premium when you know it's long-term
• Missing volume discounts for longer commitments

Accepting overage charges without caps:

• Unlimited overage at premium rates
• No monthly cap on additional hours
• Budget can balloon unexpectedly

How to Ensure Fair Pricing

Get 2-3 quotes: Understand market rate for your situation. Don't just hire the first person, but also don't just hire the cheapest.

Understand what you're comparing: £4,000 for 2 days from junior CTO versus £6,000 for 3 days from senior CTO might favour the latter if quality matters.

Negotiate based on commitment: Offering 12-month commitment? Ask for 10% discount. Most fractional CTOs prefer stable longer-term engagements.

Set clear scope and boundaries: Written agreement on days/month, what's included, what's extra, overage rates, notice period. Prevents disputes.

Include trial period: 3-month trial with 30-day notice lets both sides exit if fit isn't right, reducing risk of expensive mistake.

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Real Budget Scenarios: Three UK Businesses

Scenario A: £2M E-Commerce Startup (Manchester)

Situation: Growing fast, 4 developers, no technical leadership. Platform having scaling issues, considering platform rebuild.

Budget breakdown:

• Monthly retainer: £5,000 (3 days/month)
• Tools/software: £75/month
• Quarterly in-person: £250/month average
• Occasional overages: £300/month average
• Total monthly: £5,625
• Annual budget: £67,500

What they got:

• Platform assessment showing rebuild not needed (saved £150,000)
• Scaling architecture for current platform (cost £25,000)
• Hired senior developer (with CTO guidance, avoided bad hire)
• AWS optimization (saving £18,000/year)

Year 1 ROI: £67,500 investment, £150,000+ value delivered (223% return)

Scenario B: £6M SaaS Scale-Up (London)

Situation: 9 developers, VP Engineering in place, need strategic CTO guidance. Raising Series A.

Budget breakdown:

• Monthly retainer: £8,000 (4 days/month)
• London premium: (included)
• Tools/software: £100/month
• Overages: £500/month (higher during fundraising)
• Total monthly: £8,600
• Annual budget: £103,200

What they got:

• Technical due diligence preparation for Series A
• Architecture review and roadmap (impressed investors)
• VP Engineering mentoring (improved team performance)
• Vendor contract negotiations (saved £35,000/year)
• Helped close £3M Series A

Value: Series A success partially attributed to strong technical story. £35,000/year ongoing savings. ROI: Immeasurable (fundraising success) + 34% on cost savings alone.

Scenario C: £500K Early-Stage Startup (Birmingham)

Situation: Pre-seed, technical founder left, 2 remaining developers, need immediate CTO cover.

Budget breakdown:

• Monthly retainer: £4,000 (2.5 days/month)
• Tools/software: £50/month
• No travel: (fully remote)
• Minimal overages: £100/month
• Total monthly: £4,150
• 9-month engagement: £37,350

What they got:

• Immediate technical leadership (stabilized team)
• Security audit and fixes (prevented potential breach)
• Documented codebase and architecture
• Recruited full-time CTO (helped define role and assess candidates)
• Smooth handover to new full-time CTO

Value: Avoided 6-12 months without technical leadership. Security fixes prevented potential £50,000+ breach. Successful full-time CTO hire. Total value: £80,000-120,000 for £37,350 investment (214-321% ROI).

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Your Budget Planning Checklist

Use this to calculate your specific budget:

Step 1: Determine Your Base Retainer

• What's your revenue stage? £______M
• How many days/month do you need? _____ days
• Base retainer estimate: £______/month

Step 2: Factor In Your Situation

• Simple tech stack: -10% adjustment
• Complex/regulated: +15-20% adjustment
• Need specialized expertise: +20-30% adjustment
• London location: +15-20% adjustment
• Adjusted base: £______/month

Step 3: Add Hidden Costs

• Tools/software: +£50-100/month
• Travel (if needed): +£250-1,000/month
• Occasional overages: +10-15% buffer
• Total monthly budget: £______/month

Step 4: Calculate Annual Investment

• Monthly budget × 12: £______/year
• Add: First month onboarding overhead: +£1,500
• Year 1 total investment: £______

Step 5: Compare to Alternative

• Full-time CTO Year 1 cost: £235,000-250,000
• Your fractional cost: £______
• Savings: £______

Step 6: Calculate Expected ROI

• Mistake prevention value: £80,000-200,000
• Cost optimization: £30,000-60,000/year
• Better hiring: £50,000-100,000
• Conservative total value: £160,000-360,000
• Your investment: £______
• Expected ROI: _____% (usually 200-400%)

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Next Steps: From Budget to Engagement

You've got your budget. Now what?

1. Get board/co-founder approval

• Use the business case frameworks above
• Present 3-month trial with 30-day notice (reduces perceived risk)
• Show comparison to full-time CTO cost
• Emphasize ROI, not just cost

2. Define your specific needs

• Days per month required
• Key priorities first 90 days
• Remote vs in-person requirements
• Specialized expertise needed?

3. Start your search

• Get 2-3 candidates to interview
• Ask about their experience with businesses at your stage
• Request references from similar companies
• Clarify pricing and what's included

4. Negotiate clear terms

• Monthly days/hours clearly defined
• What's included vs what costs extra
• Overage rates and caps
• Notice period (typically 30 days)
• Success metrics for first 90 days

5. Plan for success

• Clear onboarding plan
• System access arranged
• Regular check-in schedule
• Success criteria defined

Want help determining the right budget for your specific situation? Book a free 30-minute consultation. We'll review your business stage, technical needs, and help you calculate a realistic budget that makes financial sense.

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Summary: Your UK Fractional CTO Budget Guide

The core budget ranges:

• £3,000-4,500/month for early stage (£1M revenue or less)
• £4,500-7,000/month for growth stage (£1-5M revenue)
• £7,000-10,000/month for scale-up stage (£5-10M revenue)
• £10,000-15,000/month for established (£10M+) or transition to full-time

Add 10-20% for: Tools, occasional travel, overages, and hidden costs

The business case: Fractional CTO typically delivers 200-400% ROI in Year 1 through mistake prevention, cost optimization, and better decisions.

Compared to full-time: Save £130,000-180,000/year whilst getting 70% of the value. Upgrade to full-time when you hit £8-10M revenue or 15+ person tech team.

Warning signs: Under £3,000/month gets junior talent or insufficient time. Over £12,000/month, you should hire full-time.

How to decide: Calculate your specific budget using the checklist above, get 2-3 quotes, compare to alternatives, start with 3-month trial.

The right fractional CTO saves far more than they cost. The question isn't "can we afford this?" It's "can we afford NOT to have proper technical leadership?"

Read the complete cost comparison: Fractional CTO UK vs Full-Time (2025 Guide)

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About the Author

Jake Holmes has worked with 15+ UK businesses (£1-10M revenue) on fractional CTO engagements and technology leadership decisions. He's helped companies budget properly, negotiate contracts, and achieve strong ROI from fractional CTO investments. Before founding Grow Fast, Jake was a software engineer and technical lead, giving him the technical depth most consultants lack.

Connect: jake@grow-fast.co.uk | LinkedIn | Book consultation

About Grow Fast

Grow Fast helps UK businesses (£1-10M revenue) make smart technology decisions without wasting money. Our Fractional CTO services provide strategic technical leadership 2-5 days per month at £5,000-8,000/month, saving you £120,000+ versus hiring full-time whilst getting the expertise you actually need. Book a free 30-minute call to discuss your technical leadership needs and get honest budget guidance.