Most billing leaks in solo practice aren't dramatic. They're five-minute phone calls that never got logged, invoice descriptions that generate a dispute, time that piled up for six weeks before you touched it. None of these mistakes are obvious in the moment — which is exactly why they compound. Here's where the revenue actually goes.
Reconstructing Time From Memory Instead of Logging in Real-Time
You finish a call, close a draft, or wrap a research session — and tell yourself you'll log it later. Later arrives two days after the fact, and you're guessing. Not roughly guessing. Confidently guessing low, because underestimating feels more defensible than overestimating.
Memory-based time entry is systematically inaccurate in one direction: downward. Every attorney who has audited their own logs against calendar or email records has found the same thing. The gap between what was worked and what was billed is real.
Start a timer when the work starts. Stop it when the work stops. Log the entry before you move to the next task. This takes five seconds and requires no discipline beyond the moment of transition — which is the only moment you have accurate information.
Not Billing for Short Phone Calls and Email Responses
A 10-minute call feels too short to bill. A two-paragraph email reply feels like a courtesy. Neither instinct is correct. Your engagement letter covers professional services — not just depositions and motions. Short work is still billable work, and it adds up across a week in ways that would surprise you if you tracked it.
The underlying problem is usually psychological: billing 0.2 hours feels petty. It isn't. The client isn't paying for the time you spent on the call — they're paying for your judgment, availability, and professional attention. Those have the same hourly value regardless of duration.
Set a minimum billing increment (0.1 or 0.2 hours) and apply it consistently. Log every call, every substantive email response, every review — regardless of how short. Consistency protects you from disputes and from your own instinct to give time away.
Vague or Missing Matter Descriptions on Invoices
"Legal services" is not a description. Neither is "review documents," "telephone conference," or "research." These entries invite questions — and clients who have questions about invoice line items pay them later, dispute them more often, and retain you less readily.
Vague descriptions also create exposure. If a fee dispute reaches arbitration or the bar, you need contemporaneous records showing what work was done for which matter. A four-word entry reconstructed from memory three months later is not that.
Write one specific sentence per entry: what you did and which matter it advances. "Reviewed motion to dismiss filed by opposing counsel; drafted outline for response brief" takes 15 seconds to write and eliminates every follow-up question that entry would otherwise generate. Write it while the work is fresh — not at invoice time.
Mixing Attorney and Paralegal Work Under a Single Rate
If you do paralegal-level tasks at your attorney billing rate, two things can happen: the client accepts it and overpays, or the client pushes back and you have a dispute. Neither is a good outcome. Paralegal work billed at paralegal rates is defensible and transparent. The same work billed at $400/hr because that's the only rate on file is not.
Conversely, if you have a paralegal doing substantive work that never gets billed at their rate — because it's easier to just bill everything under your rate — you're either discounting work or creating an invoice that looks inflated. The rates exist for a reason.
Assign the correct role — attorney or paralegal — to each time entry at the moment you log it. Most active matters will have both. An invoice that clearly shows attorney time at attorney rates and paralegal time at paralegal rates is easier to read, easier to pay, and easier to defend.
Letting Unbilled Time Pile Up Before Invoicing
End-of-month invoicing is the default in most solo practices. It's also one of the more expensive habits you can have. Time entries get stale — descriptions become less precise, entries get lost, and by the time you're generating the invoice, you're already doing reconstruction work on entries from four weeks ago.
Delayed invoices are also paid later. A client who receives an invoice the same week the work was done is paying for something recent and top-of-mind. A client who receives it six weeks later is reviewing a document that feels like history — and disputes correspondingly more.
Invoice frequently. Weekly or bi-weekly billing on active matters is standard in high-performing practices and is not considered unusual by clients. Shorter cycles mean more accurate entries, faster payment, and less time spent on monthly billing marathons. Invoice when the work is done, not when the calendar page flips.
The checklist — five things worth auditing in your practice
- Log time at the moment of work, not from memory at end of day or end of week
- Bill all professional time — including short calls and email responses — at a consistent minimum increment
- Write a specific one-sentence description for every time entry before closing the task
- Assign the correct rate (attorney vs. paralegal) to each entry at the time of logging
- Invoice on a weekly or bi-weekly cycle — not monthly — to reduce disputes and improve collections
Built around how solo attorneys actually work.
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