Employee utilisation rate is the percentage of an employee’s available working hours spent on billable or productive work. It is calculated as billable hours divided by total available hours, multiplied by 100. Most professional services firms target 70–80%, though optimal rates vary by industry.
Utilisation rate is arguably the single most important operational metric in professional services. It determines whether a firm can cover its costs, generate profit, and allocate work fairly across its team. Yet many firms get the calculation wrong — either by including the wrong hours in the denominator, conflating billable and productive utilisation, or ignoring the AI agents now handling billable work alongside human staff.
This guide covers the exact formula, worked examples, industry benchmarks, and practical strategies for improvement — including how to account for AI agents in your utilisation metrics.
What Is Employee Utilisation Rate?
Employee utilisation rate measures the proportion of an employee’s available time that is spent on billable or directly productive work. It is the primary indicator of how effectively a firm converts its labour capacity into revenue-generating output.
The core formula is straightforward:
Utilisation Rate = (Billable Hours ÷ Total Available Hours) × 100There is an important distinction between billable utilisation and productive utilisation. Billable utilisation counts only hours that can be charged to a client. Productive utilisation includes billable hours plus time spent on internal work that contributes to the firm’s operations — business development, training, internal tooling, and process improvement.
Both metrics are useful. Billable utilisation drives revenue analysis. Productive utilisation gives a fairer picture of how hard someone is actually working. A senior partner who bills 50% of their time but spends 30% on business development is not underperforming — they are fulfilling their role. Tracking only billable utilisation would miss that.
For professional services firms — consulting, legal, accounting, agencies — utilisation rate directly links to profitability. If your team’s average billable utilisation drops below target, revenue falls while fixed costs (salaries, office space, software) remain unchanged. Understanding what billable hours are is the foundation for getting this right.
How to Calculate Employee Utilisation Rate
Calculating utilisation rate requires three steps: defining available hours, tracking billable hours accurately, and applying the formula.
Step 1 — Define total available hours
Total available hours are not simply 40 hours per week multiplied by 52 weeks. You must subtract:
- Public holidays (typically 8 days in the UK)
- Annual leave (28 days statutory minimum including bank holidays)
- Average sick leave (4–5 days per year)
- Mandatory training days
- Company meetings and all-hands events
Worked example: A UK-based professional with 25 days of annual leave, 8 bank holidays, 5 sick days, and 3 training days has 220 working days per year. At 8 hours per day, that is 1,760 available hours.
Step 2 — Track billable hours
Billable hours are hours spent on work that is directly chargeable to a client engagement. This requires consistent, accurate time tracking. For methodology, see how to calculate billable hours.
Worked example: The same professional logs 1,320 billable hours over the year.
Step 3 — Apply the formula
Utilisation Rate = (1,320 ÷ 1,760) × 100 = 75%This professional has a 75% billable utilisation rate — within the healthy range for most professional services roles.
Individual vs team vs firm-wide utilisation
The formula works at every level. For a team, sum all billable hours across team members and divide by the sum of all available hours. For the firm, do the same across all staff. Team and firm averages smooth out individual variation, but tracking at the individual level is essential for workload management and performance conversations.
Common calculation mistakes
- Including non-working days in available hours. This deflates the rate and makes everyone look underutilised.
- Counting internal work as billable. This inflates the rate and masks revenue problems.
- Ignoring part-time staff. A part-time employee with 880 available hours and 660 billable hours has a 75% utilisation rate — the same as a full-time employee. Scale the denominator correctly.
Industry Benchmarks for Utilisation Rate
Target utilisation rates vary by industry, role seniority, and business model. The following benchmarks represent typical targets for fee-earning staff.
| Industry | Target Utilisation Rate | Notes |
|---|---|---|
| Management consulting | 70–80% | Senior consultants at the higher end; partners lower due to BD responsibilities |
| Legal firms | 60–70% | Associates typically 65–70%; partners 50–60% due to client development |
| Creative and digital agencies | 65–75% | Account managers lower; production staff higher |
| Accounting firms | 60–70% | Seasonal variation; audit season pushes rates higher |
| Software development | 70–80% | Depends on sprint planning methodology and internal tooling time |
| Architecture and engineering | 65–75% | Project-based with significant pre-tender non-billable work |
Why 100% utilisation is neither realistic nor desirable
A 100% utilisation rate means every available hour is billed to a client. No time is spent on training, business development, team management, process improvement, or strategic thinking. Firms that push for rates above 85% consistently see increased burnout, higher staff turnover, declining work quality, and a shrinking sales pipeline.
The non-billable time in a healthy utilisation rate is not waste — it is investment. Training improves future delivery quality. Business development fills the pipeline. Internal process improvement reduces future delivery costs. The benchmark ranges above account for this.
Key Takeaway: A good employee utilisation rate for most professional services firms is 70–80% for delivery staff. Rates above 85% sustained over several months indicate potential burnout risk. Rates below 60% for fee-earning roles signal a capacity, scoping, or sales pipeline problem that needs immediate attention.
How to Improve Employee Utilisation Rate
Improving utilisation is not about making people work harder. It is about removing friction, improving allocation, and ensuring that available capacity is matched to billable demand.
Improve project scoping and resource allocation. Under-scoped projects create unbillable overruns. Over-staffed projects dilute individual utilisation. Accurate scoping — informed by historical data on similar engagements — directly improves utilisation by ensuring that booked capacity matches actual billable need.
Reduce non-billable administrative burden. Every hour spent on timesheets, expenses, internal reporting, and administrative tasks is an hour not billed. Streamline internal processes. Automate where possible. If your team spends 5 hours per week on admin, reducing that to 2 hours adds 3 billable hours per person per week — a meaningful utilisation uplift across a team.
Improve time tracking accuracy and compliance. Poor time tracking does not just affect invoicing — it distorts utilisation data. If team members are not logging all billable hours (a common problem when timesheets are filled in retrospectively), your measured utilisation will be lower than reality. Real-time tracking produces more accurate data.
Balance utilisation with employee wellbeing. Sustained high utilisation without adequate recovery leads to attrition. The cost of replacing a professional services employee — recruitment, onboarding, lost productivity — far exceeds the revenue from a few extra billable hours. Set utilisation targets as ranges, not minimums, and monitor trends over quarters rather than individual weeks.
Use AI agents to handle low-value tasks. AI agents can take on research, document drafting, data processing, and other tasks that consume human hours without requiring human judgement. This frees up human capacity for higher-value billable work, improving utilisation without increasing workload.
Including AI Agents in Utilisation Metrics
The definition of “workforce” is expanding. AI agents now handle tasks that were previously performed by human staff — research, document review, code generation, data analysis, and content drafting. If these tasks are billable (or contribute to billable deliverables), then AI agent output should be part of your utilisation picture.
Why AI agents should be tracked
If an AI agent produces 20 hours of billable-equivalent work per week, that capacity exists whether you measure it or not. Ignoring it means your firm’s total productive output is higher than your utilisation metrics suggest — which distorts resource planning, pricing decisions, and capacity forecasting.
How to measure AI agent utilisation
AI agents do not have “available hours” in the traditional sense. Instead, measure utilisation as:
AI Agent Utilisation = (Billable-Equivalent Output Hours ÷ Allocated Capacity) × 100Billable-equivalent output hours are the human hours that the AI agent’s work replaces or augments. Allocated capacity is the time window or task volume assigned to the agent. For a deeper framework, see AI agent utilisation rate.
Blended utilisation: humans and AI as one workforce
The most useful metric for modern professional services firms is blended utilisation — a weighted average of human and AI agent utilisation that reflects the full delivery team.
Worked example:
- 10 human staff, average utilisation 75%, total available hours 17,600/year = 13,200 billable hours
- 3 AI agents, producing 5,200 billable-equivalent hours/year at 80% utilisation
- Blended billable hours: 13,200 + 5,200 = 18,400
- Blended available capacity: 17,600 + 6,500 = 24,100
- Blended utilisation: (18,400 ÷ 24,100) × 100 = 76.3%
This gives leadership a single number that represents the true productive capacity of the entire delivery operation — human and AI combined. Traditional time tracking tools cannot produce this number. You need a platform that tracks both.
Track Utilisation for Your Entire Workforce
Keito measures utilisation across humans and AI agents, giving you a complete picture of team productivity.
Frequently Asked Questions
What is a good employee utilisation rate?
A good employee utilisation rate depends on the industry and role. For most professional services delivery staff, 70–80% is the target range. Consulting firms typically aim for the higher end (75–80%), while legal and accounting firms often target 60–70% to account for business development and client relationship activities. Rates consistently above 85% indicate potential burnout risk, while rates below 60% for fee-earning roles suggest a capacity or pipeline problem.
How do you calculate employee utilisation rate?
Divide the employee’s total billable hours by their total available hours, then multiply by 100. Available hours should exclude holidays, annual leave, sick days, and mandatory training. For example, a professional with 1,760 available hours who logs 1,320 billable hours has a utilisation rate of 75%. The same formula applies at team and firm level by summing hours across all relevant staff.
What is the difference between billable and productive utilisation?
Billable utilisation counts only hours charged to clients. Productive utilisation includes billable hours plus time spent on valuable internal work — business development, training, mentoring, process improvement, and internal projects. Productive utilisation gives a more complete picture of how effectively someone is using their time, particularly for senior staff whose roles include significant non-billable responsibilities. Most firms track both metrics.
Why is 100% utilisation bad?
A 100% utilisation rate means every available hour is billed to a client, leaving no time for training, business development, team management, or strategic thinking. Firms that sustain rates above 85% typically experience increased burnout, higher staff turnover, declining work quality, and a shrinking sales pipeline. The non-billable time in a healthy utilisation target is an investment in the firm’s future capacity and quality, not wasted time.
How do you include AI agents in utilisation metrics?
Measure AI agent utilisation by dividing the agent’s billable-equivalent output hours (the human hours the AI work replaces or augments) by its allocated capacity. Then calculate blended utilisation — a weighted average of human and AI utilisation — to get a single metric for the full delivery team. This requires a tracking platform that can attribute AI agent output to client engagements alongside human time entries.