What makes an hour billable?
An hour is billable when it was spent doing identifiable work for one identifiable client, and when the agreement with that client says such work is charged by time. The structure comes straight from how the bill has to read. Court and bar guidance on fee applications expects each entry to name the date, the amount of time in tenths of an hour, and the work performed in enough detail that someone else can judge whether it was necessary. If an entry cannot be attributed to one client and one task, it is not billable time in the sense that survives review, whatever else it might have been. That test is worth applying even when nobody is going to review your bill.
Why tenths of an hour?
Six minutes is one tenth of an hour, which makes it the smallest unit that multiplies cleanly against an hourly rate. The Northern District of California's billing chart for appointed counsel converts minutes into tenths directly, with 1 to 6 minutes becoming 0.1 and 25 to 30 minutes becoming 0.5. Duke University's payroll chart uses tenths as well but rounds to the nearest one, so 1 minute is 0.0 rather than 0.1. Tenths are a convention, not a law, and quarter-hour increments remain in use. The unit you choose has real consequences, which is why the next section exists.
| Hours at work each week | Billable hours each week | Utilization | Billable hours a year |
|---|---|---|---|
| 40 | 30 | 75 percent | 1,440 |
| 50 | 37.5 | 75 percent | 1,800 |
| 50 | 40 | 80 percent | 1,920 |
| 55 | 44 | 80 percent | 2,112 |
| 60 | 45 | 75 percent | 2,160 |
How minimum increments inflate a bill
The State Bar of California's arbitration advisory on bill padding works the arithmetic. A lawyer billing in minimum increments of 0.25 hours at 300 dollars an hour completes four separate tasks in a day, each taking under three minutes. Four times 0.25 hours times 300 dollars is 300 dollars, charged for under twelve minutes of actual work, an effective rate above 1,500 dollars an hour. The advisory notes that courts and fee arbitrators treat high increments with suspicion, and that the judicious response to brief activities is to not record them, aggregate them with related work, or write them off. The same advisory flags large whole-number entries such as 8.0, 9.0 or 10.0 as probably estimates that should be scrutinized, while noting exceptions for trial, mediation, day-long depositions and similar extended events.
Block billing and why detail protects you
Block billing means putting one time charge against several separate tasks, from a single 200-hour line for work on a case down to a 3.6-hour entry covering four different activities. The California advisory's objection is precise: a client cannot tell how long any one task took, and cannot tell which of the listed tasks are chargeable and which are not. Its example is a lawyer who spends three of those 3.6 hours driving to retrieve a file, work that in most cases would not be compensable at a lawyer's rate. Courts have discretion to penalize the practice. Recording each task separately as it happens is less work than defending a block afterward.
In short
- A billable hour is time attributable to one client and one identifiable task, recorded as it happens.
- Six minutes is 0.1 hours, which is why tenths are the standard billing unit, though charts differ on how they round.
- Minimum increments of a quarter hour can produce effective rates many times the stated one, and reviewers know it.
- Large whole-number entries can read as estimates and deserve scrutiny, with exceptions for inherently extended events.
- Block billing hides which tasks were chargeable and can be discounted or struck out on review.
Related guides
- Decimal Hours, Explained: Decimal hours express a duration as a single base-10 number, because 7:45 cannot be multiplied by a rate but 7.75 can.
- Billable vs. Non-Billable Hours: Billable hours are charged to a client.
- Time Tracking for Freelancers: Freelancers track time for three separate reasons: to bill accurately, to support the records their tax authority expects, and to find out where the unpaid half of the week goes.