Home › Free tools › Billable utilisation calculator
Kavaro's Free Tools
Billable utilisation calculator for agencies (utilization calculator)
Billable utilisation is billable hours ÷ available hours. Resource utilisation is assigned hours ÷ available hours.
Enter each person's hours to see both rates, per person and for the whole team. Anyone outside the 70–85% target range for delivery roles is flagged.
Join Kavaro
When a spreadsheet stops working
A spreadsheet tells you last month's utilisation once the timesheets are in. Kavaro is resource management software for agencies and consultancies. It works out utilisation from the bookings already on the schedule, split into billable and non-billable by person, week and project, so you see who is heading over 85% or sitting on the bench while there is still time to move the work.
See next month's utilisation before it happens: try Kavaro freeYour results
84.0% resource utilisation · 66.7% billable utilisation
| Name | Available | Assigned | Resource util. | Billable | Billable util. | Revenue |
|---|---|---|---|---|---|---|
| Designer | 150 | 132 | 88.0% Over | 112 | 74.7% On target | £9,520.00 |
| Developer | 150 | 141 | 94.0% Over | 128 | 85.3% Over | £12,160.00 |
| Account manager | 150 | 105 | 70.0% On target | 60 | 40.0% Under | £4,500.00 |
| Team | 450 | 378 | 84.0% On target | 300 | 66.7% Under | £26,180.00 |
Designer and Developer are booked above 85%. A team average can look healthy while one person carries the crunch.
Account manager sits below 70% billable. Check the role first: account, sales and leadership roles plan lower than delivery roles.
How to calculate billable utilisation
- Work out available hours for the period: contracted hours minus holiday, public holidays, sickness and other time off. A full-time month is usually 140–160 hours.
- Add up assigned hours: everything the person is booked on, billable or not.
- Add up billable hours: the part of that time a client pays for.
- Resource utilisation = assigned ÷ available. Billable utilisation = billable ÷ available.
- For the team, add the hours first and then divide. Don't average the percentages, or a part-timer counts as much as a full-timer.
Worked example: a designer has 150 available hours, 132 assigned and 112 billable. Resource utilisation is 132 ÷ 150 = 88.0%. Billable utilisation is 112 ÷ 150 = 74.7%. At £85 an hour, the billable time is worth £9,520.00. Across the three people in the example, the team has 450 available hours, 378 assigned (84.0%) and 300 billable (66.7%).
Resource utilisation vs billable utilisation
Resource utilisation shows how full someone's schedule is. Billable utilisation shows how much of it earns revenue. The gap between them is booked non-billable work: internal projects, pitches, admin and meetings. A big gap is the first thing to look at when revenue is short but everyone feels busy. To see where that non-billable time goes, use the billable vs non-billable hours calculator.
Agency utilisation targets by role
The flags on this calculator use 70–85% as a planning range for delivery roles. Published figures for billable utilisation (billable ÷ available hours):
| Who | Figure | Source |
|---|---|---|
| Delivery staff, UK agencies and consultancies | 70–80% | Alto Accounting, citing BenchPress and Synergist |
| Professional services firms | 75% target; 66.4% actual in 2025 | SPI Research 2026 benchmark, via Deltek |
| Directors | 30–40% | Alto Accounting, citing BenchPress and Synergist |
Project managers and account managers usually sit between delivery staff and directors, because part of their week is client management that may not be billed. Set a target per role rather than one number for the whole agency.
How to read the result
- Over 85% resource utilisation: there is no slack for a sick day, a revision round or a new brief. Look at the next few weeks, not only this month, and move work before it slips.
- Under 70% billable on a delivery role: the person is either on the bench or booked on internal work. Both are fixable, but they need different fixes.
- High resource, low billable: the team is busy on work nobody pays for. Check pitches, internal projects and unbilled overruns.
- A healthy team average: check the individual rows anyway. In the example the team is 84.0% booked, on target, while the developer is at 94.0%.
This calculator looks back at one period. To see the same numbers for the coming weeks from your live schedule, try Kavaro free for 30 days or read how it works for agency resource management.
Want to see the coming weeks in a spreadsheet first? The free agency resource planning template plans people across projects for 12 weeks, with pitches weighted by their chance of winning.
Why 100% utilisation is not the goal
A team planned at 100% has no room for leave, sickness, sales support, training or the work that never makes the timesheet. Overruns then land on evenings and weekends, and quality drops. Most agencies plan delivery roles at 70–85% so the plan survives a normal week.
Questions people ask
How do I calculate billable utilisation?
Billable utilisation = billable hours ÷ available hours. Available hours are contracted hours minus holiday, public holidays and other time off. 112 billable hours out of 150 available is 74.7%. For a fuller walkthrough, see how to calculate utilisation rate for agencies.
What is the difference between resource utilisation and billable utilisation?
Resource utilisation is assigned hours ÷ available hours: how full someone's schedule is. Billable utilisation is billable hours ÷ available hours: how much of their time a client pays for. Someone can be fully booked on internal work and still have low billable utilisation.
What is a good utilisation rate for an agency?
Delivery staff at UK agencies and consultancies typically target 70–80% billable utilisation, and directors 30–40% (Alto Accounting, citing BenchPress and Synergist). SPI Research's 2026 professional services benchmark puts the target at 75% and the 2025 actual at 66.4%. 100% is not a healthy target.
Is utilisation the same as utilization?
Yes. Utilisation is the UK spelling and utilization is the US spelling. The formula is the same.
Is this the same as a credit utilisation rate?
No. Credit utilisation is the share of a credit limit you use. This calculator measures staff time: how much of a team's available hours are booked and billed.