What it means
A consultant works six hours for one client and two hours on internal tasks, and a time sheet records the date, person, duration and work category so that the firm's systems can use the record for the right purpose. For payroll, accurate hours can affect pay and overtime: ADP describes time sheets as a method of tracking worked hours for payroll, though the exact legal record and overtime rules depend on the worker's location and employment terms.
For client billing, the entry may need a matter, project or task code and a useful description, and a recorded hour is not automatically billable because the contract may have a fixed fee, cap or approval rule. For project costing, time entries help allocate labour to work, so a project that uses far more hours than planned may be underpriced or poorly scoped.
Compare labour cost with revenue and expected future work, not hours alone. Log time close to when the work happens, since reconstructing an entire month from memory creates avoidable errors and a simple daily habit can be easier than a detailed end-of-month rescue.
Choose a level of detail that people can use: 'Client work' may be too vague to support billing or analysis, while fifteen-minute narratives for every internal task may waste time. Agree categories with finance, payroll and project leads.
A manager should review entries for omissions and surprising patterns, because approval confirms the record was checked and should not be a rubber stamp. Workers need a route to correct mistakes without erasing the original change history.
Recording time is not identical to measuring productivity, since a faster expert may create more value in fewer hours, so avoid rewarding long entries or pressuring staff to relabel necessary internal work as billable. An illustrative billable share is billable hours divided by total recorded working hours for a period, so thirty billable hours out of forty recorded equals 75%, and the denominator should be stated before comparing teams.
A high billable share is not always better, because a team needs time for development, administration and quality checks, and some hours also belong to future sales or a client's fixed-price project, where billing is not tied to each hour. QuickBooks describes using time and payroll data to track hourly labour costs by project, and the internal costing rate may include wages and employer costs while the client billing rate may be different, so mixing the two can misstate margin.
If people work on multiple projects, ask them to allocate time to the right one, since a generic overhead bucket may make one project look profitable while another absorbs the cost. Handle breaks, travel, on-call time and paid leave according to the relevant policy and local law, and check contractor arrangements against the statement of work, because an approved contractor time sheet may evidence services delivered without settling whether a disputed extra fee is owed.
When a time sheet is missing, follow up before payroll or billing closes and do not invent hours, and review reports for recurring overtime, unbilled work and project overruns, because a time sheet is evidence for a question, not the answer itself.
In practice
Real-world examples.
Example
A consultant records six client hours and two internal hours on the same day.
Example
A manager checks an unusual overtime entry before payroll closes.
Example
A project lead compares budgeted and actual labour hours after a milestone.
Formula
Calculation
Illustrative billable share = billable hours / total recorded working hours x 100. 30 / 40 = 75%; define the denominator and contract billing rules.
Costing needs a second calculation. Suppose a fictional project budgeted 100 hours at an internal cost of $50 an hour, or $5,000, and the time sheets show 120 hours. The actual labour cost is 120 x $50 = $6,000, an overrun of $1,000 or 20% of the budgeted cost. If the client pays a fixed fee of $9,000, labour is $6,000 / $9,000 = 66.7% of revenue, and the team should check whether the extra hours reflect poor scoping or genuine extra demand.Case study
Seen in the real world.
This entirely fictional example follows Horizon Advisory, an invented firm whose staff filled in monthly time sheets from memory. A review found several missing project codes and uncertain client hours. The firm moved to daily entries and weekly review, then corrected its project-costing reports. It did not assume that every newly recorded hour could be invoiced under existing client agreements.
Watch out
Common mistakes.
- Reconstructing a month of hours from memory.
- Treating every recorded hour as billable under the client contract.
- Using a billable percentage as a direct measure of employee performance.
Questions
People also ask.
What is a time sheet?
A dated record of hours worked, sometimes split by client, project or task.
Why does it matter?
It supports accurate pay, contract-based billing and project labour costing.
How often should it be filled in?
As close to the work as practical; daily entry often limits memory errors.
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