How to Track Billable Hours (Step by Step, Without Losing Time)

Every solo professional who bills by the hour has the same quiet problem: the hours you work and the hours you invoice are not the same number. The gap is rarely dramatic — a forgotten phone call here, a "quick" email there, a Friday spent reconstructing Tuesday. But at $200 or $300 an hour, a leaky week costs more than most software costs in a year.

This guide is a complete, practical system for tracking billable hours. It works on paper, in a spreadsheet, or in a program; the tools change, the habits do not.

Quick answer

• Record time the same day you work it — reconstructed time always comes up short.
• Bill in one consistent increment (0.1 hour is the professional standard) and state it in your engagement letter.
• Structure everything as client → matter → entry, so invoices assemble themselves.
• Write descriptions for the client who reads the invoice, not for yourself.
• Track non-billable time too — it shows you where the leaks are.
• Review the week every Friday: unbilled hours, missing entries, matters going over budget.

Step 1. Pick your increment and stick to it

The billing increment is the smallest unit of time you charge. In US law practice the standard is 0.1 hour — six minutes. Consultants often use 0.25 (fifteen minutes) or 0.5.

Increment	A 4-minute call bills as	Feel
0.1 h (6 min)	0.1 h	Standard in law; precise, fair
0.25 h (15 min)	0.25 h	Simpler; rounds up hard on short tasks
0.5 h (30 min)	0.5 h	Only for long-block work like workshops

Smaller increments look fairer on the invoice and survive client scrutiny better. Whatever you choose: put it in the engagement letter, and round the same way every time. Inconsistent rounding is one of the first things a cost-conscious client notices.

Step 2. Set up clients and matters before you track anything

Hours do not float free — every entry belongs to a client and, within a client, to a matter (lawyers) or project (consultants). This two-level structure is what makes everything downstream automatic: invoices per matter, reports per client, budgets per project.

Set each matter up with:

• a name the client will recognize on an invoice ("Estate plan", not "Dawson #3");
• its rate — your standard rate, a negotiated client rate, or a flat fee;
• a budget or estimate, if you gave one, so you can see when reality drifts.

If a client calls about something new, resist logging it under the old matter "for now." Thirty seconds creating the matter saves an hour of untangling at invoice time.

Step 3. Capture time as it happens

There are only two capture methods that work long-term:

1. The timer. Start it when the call starts, stop it when the call ends. Best for interrupt-driven days. The catch: you must actually start it, so put the timer one click away.
2. Same-day entries. At the end of each work block — or at worst, at 5 p.m. — write down what you did, for whom, and how long. Best for people who find timers fussy.

What does not work is reconstructing the week on Friday. Billing consultants and bar-association practice-management advisors have said the same thing for decades: time written down late is time undercounted. The short calls disappear first, and short calls are exactly what a 0.1-hour increment is designed to capture.

A practical habit stack for the timer-averse:

1. Keep the day's entry list open on the second monitor (or a legal pad on the desk).
2. After every call or email session over five minutes, add one line.
3. Before shutting down, check the calendar against the list — meetings are the most commonly forgotten entries.

Step 4. Write descriptions that survive the invoice

Every entry needs a description, and the description has one reader: the client reviewing your invoice. The test is simple — would you pay this line without calling to ask?

Weak	Strong
Work on case	Draft motion to compel discovery responses
Phone call	Call with opposing counsel re: deposition scheduling
Research	Research Ohio statute of limitations for written contracts
Emails	Review and respond to client questions on settlement terms

Rules of thumb:

• Start with a verb: draft, review, call, research, revise, prepare.
• Name the document, person or issue.
• Never bundle unrelated work in one line ("various tasks" is an invitation to dispute the whole invoice).
• Keep client-confidential details out — the description should be specific about the work, not the secrets.

Step 5. Track the non-billable time too

This feels like extra work. It is actually where the money is. When everything you do gets a line — billable or not — you learn things like:

• Tuesday's "quick" website fiddling was 2.5 hours;
• you spend four hours a week on admin a $25-per-hour assistant could do;
• one client's "one quick question" calls total three unbilled hours a month — which either becomes billable under your engagement letter, or becomes a conversation.

Mark each entry billable or not, and keep the non-billable rate at zero. The weekly report does the rest.

Step 6. Close every week

Fifteen minutes every Friday:

1. Fill the gaps. Compare calendar and email against the week's entries. Add what is missing while you still remember it.
2. Check unbilled totals. Which matters have accumulated hours that should be invoiced this month?
3. Check budgets. Any matter drifting past its estimate gets a client email now, not a surprise invoice later.
4. Look at the billable ratio. Billable hours divided by hours worked. There is no universal "right" number, but a falling ratio is an early warning that admin is eating the practice.

The tools, honestly compared

Paper works for capture and fails at everything after — totals, invoices, reports all require re-entering the data somewhere else.

A spreadsheet is the correct starting point for many solos. It is free, transparent and yours. We built a free billable hours template with the exact columns from this guide. Its limits arrive on schedule: multiple rates, invoice numbering, unbilled tracking across many matters, and the discipline of keeping formulas unbroken.

Subscription apps (TimeSolv, Bill4Time, Toggl and the rest) do all of this well — for a monthly fee, forever, with your billing records on their servers. We compare the real costs in subscription vs one-time purchase.

Where HourAndBill fits: it is the spreadsheet's natural successor — a free Windows program with the timer, the client/matter structure, per-matter rates, PDF invoices and weekly reports from this guide built in. No subscription, and your data stays in a file on your PC. The preview shows the screens.

Common mistakes to stop making today

• Estimating instead of recording. "That was probably an hour" is how 1.4 hours becomes 1.0.
• Waiting to invoice. Hours billed 60 days late feel abstract to the client and get disputed more.
• One rate for everything. Your engagement letters can set different rates per client and per matter type; your tracking should handle that without mental math.
• Deleting instead of discounting. If you choose not to charge for something, show it on the invoice as a zero-dollar line or a discount. Clients remember generosity they can see.