AI for law firms did not create this problem
The billable hour has always punished efficiency. Templates and e-discovery shrank hours years ago. Generative AI makes the gap impossible to ignore.
ABA Formal Opinion 512 from July 2024 is direct. If you bill by the hour, you bill the time you actually spent. If AI helps you do in 20 minutes what used to take three hours, you bill 20 minutes. You cannot bill for learning the tool, and you can pass through its cost only if the client agreed in advance and you charge actual cost. Rule 1.5 still requires every fee to be reasonable.
So under straight hourly billing, faster work means a smaller invoice. The way out is not to slow down. It is to stop selling time. That is the real decision behind AI for small law firms.
This article is general information, not legal advice, and bar rules differ by state.
What small firms are doing instead
Flat fees are the most common move, and they fit the work AI speeds up most. A will and trust package. An uncontested divorce. An LLC formation with an operating agreement. A family-based green card application. A first-offense DUI through arraignment. A demand letter. A commercial lease review.
Litigation firms use staged flat fees: one price through the pleadings, one through discovery, one through trial prep. Some firms sell small business clients a monthly subscription. Contingency work does not change at all, and anything that speeds a case goes straight to margin.
Many firms end up with a hybrid: flat fees for defined work, hourly for the unpredictable parts. Most guides to AI for solo lawyers focus on speed. This pricing choice matters more.
Clients never wanted to buy your hours. They wanted the problem gone.
How to keep margin when the work gets faster
Price the outcome, not the time. One estate planning lawyer's will, power of attorney and health care directive package took about four hours at $300 an hour, so she billed around $1,200. With AI-assisted drafting from her own templates and a careful review, it takes about an hour and a half. She kept the price at $1,200 because that is what the work is worth and what her market supports. Her effective rate went from $300 to $800 an hour.
Others lower the price a little to win volume. A $995 package that takes 90 minutes can beat a $1,200 package that takes four hours, if it brings in two more clients a week. Both paths work. Staying hourly and getting faster does not.
Keep tracking time, even on flat-fee matters, so you know which ones are profitable and where scope creep eats the margin. Tier the offer: basic, standard and premium, with more review or faster turnaround at the top. Most clients pick the middle, and the tiers give you a clean way to say no to extra work.
Scope in writing. For a divorce, that might be: uncontested, no minor children, no business interests, up to two drafts of the settlement agreement. If the facts change, the price changes, and the client knew that on day one.
How to explain it to clients
Most clients prefer a flat fee. They hate opening an invoice and not knowing what it will say. Try: 'For this kind of matter I charge a flat fee of $2,500. That covers everything on this list. If something comes up outside the list, I will tell you before I do the work. You will never get a surprise bill.' Then stop talking.
Be honest about AI, ideally before they ask: 'My office uses AI tools for first drafts. I review every document before it goes anywhere, and our tools keep your information confidential. It is part of how we keep the fee where it is.'
Moving an hourly client? Show what the last three similar matters cost and offer a flat number near the middle.
What not to bill for
- Hours you did not work. Under hourly billing, time the tool saved belongs to the client.
- Time spent learning or setting up the tool. That is overhead.
- The AI subscription as a pass-through, unless the engagement letter says so and you charge actual cost with no markup.
- An 'AI fee' or technology surcharge the client did not agree to in advance.
- Time fixing the tool's errors. The client did not pick the tool.
- Flat-fee work that turned out to be easy. If you quoted $1,500 and it took an hour, that is the deal working. Do not add hours.
How Shouldered handles this
Flat fees only pay if the money actually comes in. Matthew at the Finance Desk sends each stage's invoice when the stage closes and runs law firm billing reminders on unpaid balances, inside the tools you already use. A person at your firm approves every invoice and refund before it goes out.
Deborah at the Legal Desk prepares the engagement letter from your own scope template and tracks unsigned ones. She never gives legal advice; the fee and the scope stay your decision. Simon runs HQ, the AI back office for law firms, over every desk and brings you only what needs a lawyer. See how HQ works for law firms.
Try this this week
- Pull your last ten invoices for one type of matter you do often. The average total is your first flat-fee number.
- Write a one-paragraph scope for that matter: what is included, what is not, and what triggers an extra fee. Put it in a draft engagement letter.
- Quote the flat fee on one upcoming matter of that type. Track your time anyway so you see the real margin.
- Add a sentence about AI use to your engagement letter and read the fees section of ABA Formal Opinion 512.
- Ask three recent clients by email: would you have preferred a flat fee up front?
