How to Track Billable Hours: A Practical Guide for Freelancers
· 5 min read
If you bill by the hour, your time log is your revenue. Every minute you forget to record is work you did for free, and every vague entry is a question your client might ask when the invoice lands. Learning how to track billable hours well is less about finding a perfect tool and more about building a few simple habits that make your records complete, specific, and easy to turn into an invoice.
Why accurate billable hours matter
Loose time tracking costs you in two ways. First, there's leakage: the 15-minute call you didn't log, the quick fix you "didn't count." Say you bill $100/hour and lose just 30 minutes a day to untracked work. Over a 20-day month, that's 10 hours, or $1,000 you earned but never invoiced.
Second, there's trust. A line that says "Website work – 12 hours" invites pushback. A breakdown that shows what you did, when, and for how long answers questions before they're asked. Detailed records also help you quote future projects more accurately, because you can see how long similar work really took.
How to track billable hours: live timer or manual entries
There are two basic ways to capture time, and most freelancers use both.
| Method | Best for | Watch out for |
|---|---|---|
| Live timer | Focused work blocks, calls, anything you start and stop deliberately | Forgetting to stop it when you step away |
| Manual entry | Work done away from your desk, quick tasks, catching up at day's end | Relying on memory days later |
A live timer is the most accurate option because it records time as it happens. Manual entries fill the gaps: the client call you took from your car, or the hour you spent reviewing a document on your phone. The key rule is to log manual entries the same day, while you still remember the details.
If you work away from your laptop often, a phone app helps. We cover that in more depth in our guide to a time tracking app for Android.
Set up clients, projects, and rates first
Before you track a single minute, set up the structure your invoices will need:
- Clients – one entry per paying customer.
- Projects – separate projects under each client (for example, "Website redesign" and "Monthly maintenance").
- Rates – a default hourly rate, plus overrides for clients or projects that pay differently.
This takes ten minutes and saves hours later. When every entry is tied to a client and project, your time reports and invoices can group work automatically instead of you sorting it by hand at month end.
Write entries your client will understand
A good time entry answers "what did you do?" in one line. Compare:
- Weak: "Dev work"
- Better: "Built checkout form validation and fixed mobile layout bug"
You don't need an essay. Aim for a short, specific description that a client could read cold and recognize. Clients are far more likely to pay promptly when an invoice is backed by entries that make sense to them.
Mark billable and non-billable time
Not everything you do for a client is billable. Internal admin, scoping calls you agreed not to charge for, or fixing your own mistakes might be non-billable. Track that time anyway, but flag it correctly. It shows you where your hours actually go and whether a client is more expensive to serve than their invoices suggest.
We break down how to decide what counts in billable vs. non-billable hours.
Decide how you'll handle rounding
Some freelancers bill exact minutes; others round to 6- or 15-minute increments. Either can be fair as long as you're consistent and your client knows your policy. A few guidelines:
- Put your rounding rule in your contract or proposal.
- Don't round every tiny task up to 15 minutes if you do many of them a day; batch them into one entry instead.
- Be conservative. Rounding that consistently favors you erodes trust faster than it grows revenue.
Review your time weekly, bill on a cycle
Tracking is only half the job. Set a weekly 15-minute review to:
- Fill in any missing entries while memory is fresh.
- Fix entries logged to the wrong client or project.
- Check the billable flag on anything unusual.
Then invoice on a predictable cycle, such as monthly or every two weeks. A regular rhythm keeps unbilled time from piling up. If you find hours slipping through the cracks, our article on how to reduce unbilled time has more tactics.
FAQ
Should I track time I don't bill for?
Yes. Tracking non-billable time shows your true effective hourly rate and helps you price future work. Just mark it as non-billable so it doesn't end up on an invoice.
What's the best increment for billing hours?
There's no universal answer. Exact minutes are the most transparent; 6-minute (0.1 hour) and 15-minute increments are common in consulting and legal work. Pick one, state it in your agreement, and apply it consistently.
How detailed should time entries be?
Detailed enough that your client can understand the work without asking. One clear sentence per entry is usually right.
Start tracking with a system that invoices for you
The best way to track billable hours is the one you'll actually stick with: a timer for focused work, same-day manual entries for everything else, and a regular review before you invoice. ClockPaid combines a live timer and manual entries with per-client rates, then turns your unbilled billable time into an invoice with the detailed time report attached. You can start free with up to two clients.