Most consultants and freelancers know the feeling. It is Friday afternoon, an invoice is due, and you are trying to rebuild the week from your calendar, your sent emails and a vague memory of a long phone call on Tuesday. Some of that time was clearly billable. Some of it was admin, internal planning or a favour to a client that you never meant to charge for. Most of it is now a guess.

The problem is rarely a lack of discipline. It is a routine that only works on quiet weeks. When the pressure rises, logging time is the first thing to slip, and the billable and non-billable line blurs exactly when it matters most.

This walkthrough sets out a routine designed to survive busy weeks. It has four steps, and none of them takes more than a few minutes.

Step 1: Decide what counts as billable before the week starts

Most arguments about billable time happen in your own head, in the moment, when you are tired. Settle them in advance instead.

For each client or engagement, write down a short, plain rule set. For example, a three-person strategy consultancy might agree on these:

  • Billable: workshops, analysis, drafting deliverables, client calls and revisions within the agreed scope.
  • Non-billable: proposals, internal team meetings, learning a new tool, and fixing our own mistakes.
  • Check with the lead first: travel time, out-of-scope requests and calls that turn into general advice.

The third category matters. It gives you a place to put the awkward items without deciding on the spot. You log them, flag them for review and move on.

Keep these rules where you will see them. If you use Tilvin, a project notebook works well for this, because the rules sit next to the client's tasks and files rather than in a separate document nobody opens. When the scope changes, update the notebook and the rule changes for everyone at once.

Step 2: Log at three fixed checkpoints, not at the end of the day

The routines that fail tend to rely on either logging every minute as it happens, which breaks the moment you get busy, or logging everything at the end of the day, which turns into guesswork by evening.

A middle path holds up better: three fixed checkpoints.

  1. Before lunch. Log the morning while it is still fresh.
  2. Mid-afternoon. Log anything since lunch, especially calls.
  3. End of day. Log the rest, then glance at the total for the day.

Each checkpoint takes two or three minutes. Tie them to something you already do, such as making a coffee or closing your laptop for lunch, so they do not depend on willpower.

On truly chaotic days, lower the bar rather than skipping. A rough entry such as "Client A, 10:00 to 11:30, workshop prep" is far more useful on Friday than a perfect entry you never made. You can tidy the description later; you cannot recover the start and end times from memory.

If you are often away from your desk, log from your phone. Tilvin's Android and iOS apps include time logging, which helps for site visits and calls taken on the move.

Step 3: Log against the work, and set the billable flag every time

A time entry is most useful when it is attached to the thing you were working on. "Three hours, Client B" tells you very little when the client asks what they are paying for. "Three hours, Client B, revising the pricing model" answers the question before it is asked.

In Tilvin, time logs can sit on a specific task or on the project as a whole. A simple rule of thumb:

  • Log against a task or sub-task when the work clearly belongs to a deliverable, such as drafting a report section or reviewing a dataset.
  • Log against the project for general client time that does not fit a single task, such as a check-in call.

Each time log has a billable flag. Make setting it part of the entry itself, not a later clean-up job. Use your rules from Step 1: if the work is clearly billable, flag it; if it is clearly non-billable, leave it unflagged; if it falls in the "check first" category, leave it unflagged and add a short note in the description such as "confirm: travel". That way nothing gets billed by accident, and the queries are easy to find during your weekly review.

Two small habits make entries much easier to defend later:

  • Write descriptions a client could read. "Updated forecast with Q3 actuals" beats "misc fixes".
  • Attach evidence where it helps. Time logs accept attachments, so a call summary or a marked-up draft can live with the hours it took.

Logging non-billable time properly is just as important. It shows where your hours really go. If proposals or internal admin are quietly eating a day a week, you want to see that in the numbers rather than feel it as a vague sense of being behind.

Step 4: Run a fifteen-minute review every Friday

The checkpoints capture the time. The weekly review makes it trustworthy. Block fifteen minutes on Friday, before any invoicing happens, and work through this list:

  1. Check for gaps. Pull a timesheet report for the week, filtered to yourself. Any day that looks thin compared with what you remember doing probably has missing entries. Fill them while the week is still recent.
  2. Resolve the "check first" items. Find the entries you noted for confirmation, decide on each one using your rules, and set the billable flag accordingly. If you need a colleague's decision, ask now rather than at month end.
  3. Review billable hours per client. The billable hours report, filtered by date and project, shows what each client has used. Compare it against estimates or retainers so you can warn a client early if they are running ahead of budget.
  4. Tidy descriptions. Rewrite any rushed entries so they make sense to someone outside your head.

For small teams, the lead can run the same review across everyone using the person filter. It is a quick way to spot one consultant who has stopped logging under pressure, which is usually a sign they are overloaded rather than careless.

When invoicing time comes, you are working from reviewed figures rather than reconstructions. In Tilvin, invoices, estimates and payments live in the same workspace as your projects; our earlier post on how Tilvin's invoice management simplifies billing covers that side in more detail. If you prefer to bill from your own spreadsheet or accounting system, time logs can be exported to Excel.

Once an invoice has been settled, mark the corresponding logs as paid using the paid flag. It keeps a clear line between hours that are billed and settled and hours still outstanding.

Putting the routine in place this week

You do not need to change everything at once. Start small and let the habit settle before you refine it.

  • Today: write a short billable, non-billable and "check first" rule list for each active client.
  • Tomorrow: try the three checkpoints. Set reminders if it helps, and accept rough entries on busy days.
  • All week: log against tasks where you can and set the billable flag as you go.
  • Friday: run the fifteen-minute review before you touch an invoice.
  • After a month: look at your non-billable hours as a whole. If one category keeps growing, decide whether to reduce it, price it into future work, or accept it knowingly.

The goal is not perfect records. It is records good enough to bill confidently, answer client questions without digging, and see honestly where your week goes. If you want to see how time logging, reports and invoicing fit together in one place, the Tilvin features overview is a good starting point.