How to track billable hours so nothing slips.

Billable hours leak in six predictable categories: the 20-minute client call you took on Wednesday and never logged; the email back-and-forth that adds up over a week; the 'quick research' that turned into two hours; the strategy thinking you did in the shower (we won't pretend you can't bill for thinking); the spec edits done at 11pm; and the post-mortem you wrote up but didn't track. All real work. Most lost to bad reconciliation a week later.

The fix isn't a smarter time tracker. It's a system that makes logging the hour cheaper than not logging the hour, plus a backstop for the times the system fails.

Option one — start a timer. The timer is the gold standard because it captures actual elapsed time, not a guess. The problem is starting it; if it takes more than one click, you'll skip it. A good tool puts the timer in the chrome of every page you'd already be on (a top bar widget, an extension, a system tray).

Option two — log it manually at the end of each work block. This is the catch-all. When you finish a focused stretch, log the duration before context-switching. Tools that parse '1.5h', '1:30', and '45m' all the same way make this faster than starting a timer in the first place.

Auto-trackers that watch what app you're in and infer billable time are not in this list on purpose. They surface time you can't actually bill for (browsing for snacks, slack, code review you didn't ask for), and the result is invoices that look wrong to clients.

The biggest leverage move in a billing setup is deciding 'is this billable?' at the moment you log the entry — not at the moment you build the invoice. By invoice time, you've lost context: was that 45-minute meeting client work or internal? Was the research truly for project A or just adjacent?

Choose the pricing policy per project. Hourly projects default tracked time to billable and let you turn individual entries off when needed. Fixed-fee and non-billable projects enforce non-billable time because their tracked hours are for delivery reporting, not hourly invoice charges.

Most agencies bill in 15-minute increments — round up at the entry level so a 17-minute call bills as 30 minutes (0.5h × rate). Hoursmith rounds each billable time entry before grouping it into invoice lines; fixed-project allocations and optional custom lines pass through at the amount selected or entered.

Round up, not 'nearest.' If a client calls you for 8 minutes, that entry bills 15 minutes rather than disappearing. Three separate 8-minute calls therefore bill 45 minutes. Make the entry-level rounding policy clear in your engagement terms so clients can predict the invoice too.

Log at the end of each work block, not at the end of the day. End of work block, while context is fresh, while you remember what 'finished the dashboard wireframes' actually included. End of day reconstruction is a known source of slip.

Build the habit by parking it next to an existing habit. Log time → save the file → close the editor → next thing. Or log time → close the meeting tab. Habit-stacking beats discipline.

No system catches 100% of entries. Reserve 10 minutes at the end of each week — Friday afternoon or Monday morning, your call — to walk back through your calendar and inbox, looking for client work you forgot to log. Most weeks you'll find 1-3 entries. That's the backstop paying for itself.

Don't try to skip this step by promising yourself you'll catch them as you go. You won't.

Tracked time should lead to the right billing outcome. For hourly projects, a good billing tool previews eligible un-invoiced entries and saves exactly the entries you select, grouped and rounded the way you bill. For fixed-fee projects, the hours remain delivery data and the invoice uses the reconciled contract balance.

If your current tool requires you to copy hours into a spreadsheet to invoice, half the value of tracking just leaked out. The integration between tracking and invoicing is the whole point.