The week I shipped a 40-hour feature and billed 32
Last March I closed out a sprint for an agency client and submitted my invoice on Friday afternoon. Standard rate, standard scope. Two weeks later I was reconciling my bank statement and noticed something off.
I had billed 32 hours. I had worked 40.
Not "felt like 40." Forty hours, blocked out in my calendar, code commits to prove it. I had simply forgotten to log eight hours across two weeks. At $60/hr that was $480 walking out the door because I had been doing what every freelancer I know does: filling in the timesheet on Friday from memory.
Why "fill it in Friday" doesn't work
The honest math on retroactive time entry:
- Monday's bug-fix you remember as "an hour" was probably 2.5 hours of context switching
- The Slack-driven scope creep on Wednesday gets logged as zero because it does not fit any project bucket
- The 20-minute calls you took between focus blocks dissolve completely
Self-reported time data tends to drift 15-30% low when filling timesheets more than 24 hours after the fact. My March invoice was right inside that band.
What I changed
I stopped trying to "remember to log time." Memory is the wrong tool. I rebuilt my workflow around three rules:
- Time gets captured at the moment, not at the end of the week. A timer that starts when I open a project's repo, stops when I close it.
- Every meeting gets a client tag. If it is billable, it gets logged before the next thing on my calendar starts.
- Friday is for reviewing, not reconstructing. I check what got captured, not invent what happened.
That is it. No new discipline, no willpower. Just moving the capture point to the moment the work happens.
How I do it now
I built FillTheTimesheet for exactly this — a passive tracker that watches what you are working on and turns it into billable line items per client. The tagline is "smart timesheet management" but really it just enforces the rule above: capture at the moment, review on Friday, never reconstruct from memory.
You do not need my tool to fix this. You do need something that captures at the moment. Toggl, Harvest, a Shortcut, a sticky note. The choice of tool matters less than killing the "I will remember on Friday" habit.
The takeaway
If you freelance and you have never audited your timesheets against your calendar, do it once this week. Pick a recent invoice, pull up the corresponding calendar week, and add up the actual time. If your invoiced hours match within 5%, you are better than most. If they do not, you just found a raise.
I am still annoyed about that $480.
