Outcome
What an unbilled hour costs
Hours logged late, adjusted by email or forgotten at month end never reach an invoice. Work out what that share costs in a year.
What it comes to
Fill in every field to see the result.
- Unbilled per year
- 43 200 €
- Unbilled per month
- 3 600 €
- Unbilled hours per month
- 48 h
How the figure is calculated
- In words
- Take the share of logged hours that never reaches an invoice, value those hours at the billing rate, then multiply by twelve.
- In symbols
- Unbilled per year = H × U × R × 12
- Unbilled per month = H × U × R
- Unbilled hours per month = H × U
- With your numbers
Fill in every field to see the result.
- 1 600 h × 3% = 48 h
- 48 h × 75 € × 12 = 43 200 €
Assumptions
- Count only billable hours on client work. Internal time was never going to be invoiced.
- Hours written off on purpose, with a reason, are a decision rather than a leak; leave them out of the share.
How Flowtly measures this
- 1Everyone logs hours against projects in Work Time, by hand or with the project timer, and the team summary shows coverage and the days still to chase.
- 2Each month, the project’s account manager reviews a draft of the client report and adjusts lines, always with a reason.
- 3Signing off locks the month’s adjustments and tells finance it can invoice. A re-opened month keeps the earlier signed report as the record.

Measure it on your own data
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