Track time as you work, not at the end of the day or week. Trying to reconstruct hours from memory leads to underreporting. You forget the 20 minutes you spent answering a client email or the quick phone call that turned into 45 minutes. Those untracked increments add up to significant unbilled revenue over a month.

Use a dedicated time tracking tool with a structure that matches how you bill. Most tools let you create clients and projects so each time entry gets assigned properly. Toggl, Harvest, and Clockify are popular standalone options. QuickBooks Online has built-in time tracking that flows directly into invoices if you’re already using it for accounting.

Include descriptions with every entry. “Client work - 2 hours” tells you nothing when you’re creating an invoice two weeks later. “Drafted proposal revisions and sent for approval” tells you exactly what happened and makes your invoice more transparent to the client. Detailed entries also help you spot which types of work take more time than expected.

Set up categories that align with your billing structure. If you bill different rates for strategy versus execution, track them separately. If some work is billable and some is administrative, make that distinction clear in your entries. The categories you use for tracking should make invoicing straightforward.

Review your time entries weekly before sending invoices. Look for gaps where you worked but didn’t log time. Check that entries are assigned to the correct client and project. Invoicing and receivables only works if the underlying time data is accurate.

Decide how you’ll handle partial hours. Some businesses round to 15-minute increments, others to 6-minute increments like law firms. Whatever you choose, be consistent and make sure clients understand your billing increments.

If you’re a small business bookkeeper or consultant doing client work, your time tracking data feeds directly into your financial picture. Accurate time records let you see which clients are profitable, which projects took longer than estimated, and whether your hourly rate makes sense given your actual hours worked.

The tool matters less than the habit. Pick something easy enough that you’ll actually use it. A complicated system you abandon after two weeks is worse than a simple spreadsheet you update consistently. The goal is capturing billable time as it happens so nothing falls through the cracks.