- Spreadsheet time tracking loses an average of 15–20% of billable time through under-recording and delayed entry.
- The best time tracking system is the one with the least friction between doing the work and recording the time.
- Five rules for setting up a time tracking system that actually gets used.
Time is the product in most professional service businesses. If you’re billing by the hour — or tracking time to understand profitability on fixed-fee work — the accuracy of your time records directly determines the accuracy of your revenue. And for most businesses running time tracking in spreadsheets, that accuracy is significantly lower than they think.
The problem isn’t effort or intention. It’s friction. When recording time requires opening a spreadsheet, finding the right row, converting the time to decimal format, and entering a description — it competes with the actual work for attention. The result is deferred entry, rounded estimates, and systematically under-recorded billable time.
What spreadsheet time tracking typically costs you
Under-recording
Time recorded at end of day is an estimate. The 8-minute call, the 12-minute email, the 20-minute review — these round down or disappear entirely. Studies consistently show 15–20% of billable time is lost this way.
Invoice disputes
When a client questions an invoice line, you need contemporaneous evidence that the work happened. A spreadsheet updated on Friday afternoon for the whole week doesn’t provide that. A timestamped time entry does.
Profitability blindness
Fixed-fee work is only profitable if the time invested is below the fee. Without accurate time recording, you have no visibility into which engagements are profitable and which are losing money.
Billing delays
Compiling a spreadsheet into an invoice is a manual process that most people defer. Deferred billing is deferred cash — and the longer you wait, the harder it is to remember what the time entries actually covered.
Five rules for a time tracking system that gets used
Time entry must take under 30 seconds
If recording a time entry takes longer than 30 seconds, it will be deferred. The winning systems are ones where you open a timer with one click, attach it to a client and matter, and stop it when you’re done. The entry is already there — you just add a description. Everything else creates friction that erodes compliance.
Every entry must be attached to a client and a matter
Time not attached to a client is time that can’t be billed or analysed. Every entry should have: client, matter/project, date, duration, and a brief description of what was done. This is the minimum needed to generate a credible invoice and defend it if challenged.
Record time as you work, not at the end of the day
End-of-day time recording is reconstruction from memory. Same-day recording is documentation. The difference in accuracy is significant — and same-day recording protects you in any dispute about what was actually done. If your system makes real-time recording practical (a timer on your desktop or phone), use it for everything.
WIP review weekly, billing monthly
Review your work-in-progress time entries weekly — not to bill them, but to check for errors, missing descriptions, and entries that were inadvertently left open. Bill on a fixed monthly cycle, not when you remember to. Predictable billing cycles set client expectations and prevent cash flow lumps.
Use time data to improve fixed-fee pricing
If you offer fixed-fee engagements, accurate time tracking tells you whether your pricing is sustainable. Track the time on every fixed-fee matter for three months. You’ll immediately see which types of work are priced correctly, which are underpriced, and which are overpriced. This is data that has direct impact on your profitability — and you can only get it from accurate time records.
What to look for in a time tracking tool
The minimum requirements: timer functionality (start/stop, not just manual entry), client and matter categorisation, description fields, and export to invoice. Beyond the minimum, useful features include: mobile app for recording time away from your desk, integration with your billing or accounting tool, and WIP reporting by client and period.
The tools you don’t need: anything with project management features you won’t use, complex approval workflows for a team of fewer than 10, or AI features that automatically categorise your time (in practice, these require constant correction and create more work than they save).
The adoption test: A new time tracking system should be tested by the least enthusiastic person on your team. If they find it faster and easier than the spreadsheet after one week, you have a system that will get used. If they revert to the spreadsheet, the tool has too much friction. Evaluate on the hardest case, not the easiest.
Time tracking built into your client management platform
HubSecure’s time tracking links directly to client records and matters — so recording time, generating WIP reports, and creating invoices all happen in the same system.
Reserve your founding seat