#billable utilization

What is the billable utilization rate?

Billable utilization rate is the percentage of an employee’s available working hours that are billed to clients. It is the single most important leading indicator of agency profitability, calculated by dividing billable hours by total available hours and multiplying by 100. Although most professional services firms target a billable utilization rate of 75% to 80%, the right target varies significantly by role.

If you run an agency, consultancy, or IT services firm, your billable utilization rate determines whether you have a margin or not. Furthermore, this guide covers the formula, industry benchmarks by role, the five most common reasons utilization rates fall below target, and six proven strategies to reach 75%+ — with a real-world worked example showing how a 12-person agency moved from 62% to 78% in a single quarter.

Billable utilization rate formula

The billable utilization rate formula is:

Billable Utilization Rate (%) = (Billable Hours ÷ Total Available Hours) × 100

This formula looks simple, but most agencies calculate it incorrectly. Specifically, the two variables — billable hours and total available hours — both require clear definitions to produce a meaningful number.