Billable Utilization Rate

Why it matters

Every point of utilization you recover turns already-paid capacity into billable output without new hires. Parakeeto notes a roughly 10-point gain on the same team can add about six figures of annual profit.

Benchmark

Delivery staff typically run about 65 to 85% on an annual basis; whole-agency utilization, counting non-delivery roles, is usually 50 to 60%. Sustained readings above roughly 80 to 85% signal understaffing or burnout, not a win.

Common mistake: dividing by all paid hours instead of true available hours after holidays and PTO, which makes the number look artificially low.

How to calculate utilization rate

Utilization rate = billable hours / available hours x 100

The formula is agreed everywhere. The denominator is not, and the disagreement is large enough to make most published benchmarks unusable.

SPI Research divides annual billable hours by a flat 2,000, leaving holiday and paid time off inside the denominator. Parakeeto uses 2,080, meaning 52 weeks of 40 hours, and says explicitly not to subtract vacation, sick days or holidays, on the grounds that netting them out makes the metric improve when somebody takes leave. FTI Consulting, in its 2024 annual filing, does the opposite and excludes public holidays while keeping vacation in.

The swing is not academic. Somebody billing 1,400 hours in a year scores 67.3% against 2,080, 70.0% against 2,000, and 74.5% once fifteen days of leave come out as well. Same person, same work, seven points apart.

What is a good utilization rate

Two audited filings settle how carefully this has to be read. For the same 2024 financial year, CRA International reported 75% utilization and FTI Consulting reported 57 to 66% across its hourly-billing segments. Both figures were filed with the SEC, both are called utilization, and a large part of the fifteen-point gap is definitional rather than operational.

The best measured reference point is SPI Research's 2025 benchmark, covering 403 professional services firms for data year 2024. It puts billable utilization at 68.9% across all firms, continuing a slide from 73.2% in 2021. Its agency vertical reads 64.4%, though on only 25 participating firms, so treat that one as directional. By firm maturity the spread runs from 59.6% at the least mature level to 83.6% at the most.

SPI's own guidance is worth repeating because it has both a ceiling and a floor. Firms above 80% tend to perform best but may not sustain it, because the cost arrives later as burnout and attrition. Firms below 50% report the worst results across every category they measure.