Law Firm Billing Cycle: How to Set a Fixed Monthly Schedule
A law firm billing cycle is the set of dated steps that turns recorded time into an invoice, and an invoice into cash. Many small firms say they bill monthly, yet invoices go out whenever someone finds an open afternoon, and that gap shows up in the bank account. Clio's 2025 Legal Trends Report puts the typical firm's lockup at about 93 days of work that is unbilled or unpaid at any given time. A fixed monthly billing schedule, with one person responsible for each step, is a direct way to shorten that wait.
What is a law firm billing cycle? A law firm billing cycle is the repeating sequence of steps that turns recorded time and costs into invoices and cash. A reliable cycle gives each step a date and an owner: time entered weekly, approved on day 1, pre-bills reviewed on day 2, and invoices sent on day 3.
Why does irregular billing slow law firm cash flow?
Irregular billing slows cash flow because every week an invoice waits adds to lockup, the money a firm has earned but not yet collected. Lockup has two parts:
Work-in-progress (WIP) lockup: work that's done but not yet billed.
Accounts receivable (AR) lockup: invoices that are sent but not yet paid.
Our guide to law firm lockup explains how to measure both in days. Clio reports that the unbilled part has been trending down while the unpaid part has been creeping up, which means clients are taking longer to pay the invoices they do receive.
Some of that delay starts with the firm. In a client survey Clio cites in its accounts receivable guide, 15% of clients said they never received a bill, and 28% said they waited a noticeably long time for one. When an invoice arrives weeks after the work, the client is paying for a month they may barely remember.
What does a fixed monthly billing schedule look like?
A fixed monthly billing schedule is a calendar that repeats every month, with the same steps on the same dates. It's more than a promise to bill once a month:
Once a monthly cycle runs smoothly, some firms move to billing twice a month, for example on the 1st and the 15th, which shortens the unbilled period again. Starting with one cycle a month keeps the change manageable for the team.
How do you keep the law firm billing process on schedule?
You keep the law firm billing process on schedule by fixing the three places it usually slips: late time entries, pre-bills waiting for approval, and matters that never produce an invoice.
Set a weekly time-entry deadline
The cycle depends on time being in the system before day 1. Time entered once a month has to be rebuilt from memory, and reconstructed entries are the ones clients question. That's why a weekly deadline matters: when time is due by Friday afternoon, the person who owns billing can check the report on Monday morning and follow up with anyone whose entries are missing.
Clear the pre-bill review bottleneck
Pre-bill review is the step where a responsible attorney checks a draft invoice before it goes to the client, and it's where many cycles stall. Billable work takes priority, and some attorneys put off a review because writing time down feels uncomfortable or because they expect a client to push back. Three habits help:
A same-day deadline: pre-bills sent on day 2 come back on day 2.
An agreed fallback: decide in advance what happens when a pre-bill isn't returned, such as the billing lead taking it to the managing partner.
A running record: track how often each attorney's pre-bills run late, because a pattern usually points to entries that need cleanup before anyone can approve them.
Track hidden lockup in flat-fee and contingency matters
Hourly matters show up on the accounts receivable report as soon as they're invoiced, but flat-fee and contingency matters can build lockup that no report shows, because no invoice goes out while the work is under way. Time and advanced case costs simply accumulate. Reviewing unbilled time and advanced costs by matter each month keeps that balance visible, and billing flat-fee work at the milestones your fee agreement allows keeps it from building up.
How do trust retainers fit into the billing cycle?
Trust retainers fit into the billing cycle as a scheduled transfer: once an invoice is issued against a retainer and the fee is earned, the firm moves its share out of trust. California Rule of Professional Conduct 1.15 requires advance fees to be held in a trust account, with a narrow written exception for some flat fees, and requires the firm's portion to be withdrawn at the earliest reasonable time after its interest becomes fixed.
In practice, that means adding the trust transfer to day 3, after invoices go out, and requesting a top-up when a client's retainer falls below the level your fee agreement sets, if the agreement provides for one. Some firms also set a larger retainer for clients who regularly pay late. A monthly IOLTA reconciliation then confirms that each client's trust balance matches the firm's records. Review your retainer terms with your own ethics counsel, because the rule's requirements depend on how each fee agreement is written.
How can online payments speed up collections?
Online payments speed up collections because clients can pay the moment an invoice arrives. Clio's accounts receivable research points to two gains:
Online payment options: firms that accept online payments see a median of 7 days to payment, against 15 days for firms that don't.
Emailed invoices: firms that email their bills have a realization rate of 91%, compared with 73% for firms that don't.
That means sending every invoice by email, offering card and ACH alongside checks, and including a payment link in each invoice. Automated email or text reminders can then handle the first follow-up. But remember: each payment option needs to deposit funds to the correct account, operating or trust, so set it up with your trust accounting rules in mind.
What does California require on a law firm bill?
California doesn't set how often a law firm must bill, but Business and Professions Code section 6148 sets what a bill must contain. Under subsection (b), each bill must clearly state its basis, including:
the amount, rate, basis for calculation, or other method used to determine the fees; and
the specific costs and expenses charged, with their amounts.
A client can also request a bill, which must be provided within 10 days, and can repeat the request at intervals of at least 30 days (section 6148 as published in the 2024 California Code). A regular cycle makes both requirements easier to meet, because the bill a client asks for has usually already gone out. Review your fee agreements and billing practices with your own ethics counsel to confirm how the statute applies to your firm.
Who should own each step of the billing cycle?
One person should own the billing calendar, and each attorney should own one deadline. At a small firm, an operations or office manager can be the billing lead, responsible for:
checking time entries every Monday morning;
sending pre-bills to responsible attorneys on day 2;
pulling the work-in-progress and accounts receivable aging reports from Clio each week.
Attorneys then own one thing each, which is returning their pre-bills by the deadline. A 15-minute weekly review of those reports with the billing lead keeps the cycle on track and shows early which matters are falling behind. Our guide to law firm KPIs covers the reports worth reviewing.
Legal billing best practices at a glance
A law firm billing cycle works when every step has a date and an owner.
Time due by Friday afternoon keeps day 1 on day 1.
Pre-bill review is the step most likely to stall, so give it a same-day deadline.
Invoices sent by email with a payment link get paid sooner.
Flat-fee, contingency, and trust-retainer matters need their own monthly check.
Frequently asked questions about law firm billing cycles
How often should a law firm send invoices?
Monthly on a fixed date is a common starting point, for example with invoices out by the 3rd of each month. Firms that want to shorten the unbilled period further move to billing twice a month once the monthly cycle runs reliably. Whichever frequency you choose, the date matters more than the interval: clients learn when to expect a bill, and the team knows when each step is due.
What is a pre-bill review?
A pre-bill review is the check a responsible attorney makes on a draft invoice before it reaches the client. The attorney reads the time entries and their descriptions, confirms costs and any write-downs, and approves the invoice for sending. Because every invoice waits on this step, a same-day deadline for pre-bill review keeps the whole billing cycle on schedule.
Does California require monthly billing?
No. California Business and Professions Code section 6148 sets what a bill must state and gives clients the right to request a bill, which must be provided within 10 days, at intervals of at least 30 days. The statute doesn't set how often a firm must bill, so the billing frequency is a business decision for the firm and its fee agreements.
What is the difference between WIP lockup and AR lockup?
WIP lockup is work that's done but not yet invoiced, so it sits in your practice management software as unbilled time. AR lockup is work that's invoiced but not yet paid, so it sits on the accounts receivable aging report. Together they make up total lockup, which is the time between doing the work and having the cash in the bank.
How do I know if my billing cycle is working?
Measure your lockup in days before and after the change, and watch your realization and collection rates in Clio each month. Realization shows how much worked time is billed, and collection shows how much billed time is paid. Our law firm lockup guide shows how to calculate lockup days from your Clio reports.
Putting the cycle in place
Counsel CPAs runs billing and back-office work for law firms inside their own Clio, including the monthly cycle described here. To get started on your own, put next month's three billing dates on the calendar today and name the person who owns each one.
Comments