Past-Due Invoice Reminders for Law Firms: What to Say at 30, 60, and 90 Days

Day 31. The invoice went out on the first of last month, the client was happy with the work, and the balance is still open. Someone on the billing team is deciding whether to send another email, how firm to make it, and whether this is the moment to loop in the responsible attorney. Past-due invoice reminders (or aged AR reminders, if you think of them by the aging bucket they come from) work best when that decision is made in advance, with language ready for each stage.

Reminders only recover money that a clear, on-time invoice already earned. If invoices go out weeks after the work, or arrive with line items the client can’t decode, the reminder sequence starts from behind. Walters Gilbreath, PLLC, a 23-lawyer family law firm, cut client inquiries about invoices from 10–15% to virtually zero by putting an account summary in the body of each invoice email. Fewer questions means fewer invoices stalled while someone waits for an answer.

Before you send past-due invoice reminders, check the invoice

Before any reminder goes out, confirm three things: the invoice was delivered to the right person, it hasn’t been disputed in a call or email the billing team didn’t see, and the balance is right after any trust application or partial payment. A reminder that lands on a disputed or misstated invoice costs goodwill and gets you nothing.

Each sample below includes the balance, the invoice date, and one way to pay the full balance. Swap the bracketed fields for your own.

At or just before the due date: a courtesy note

Send a short note a few days before or on the due date. Its only job is to put the bill back in front of the client.

Subject: Invoice from [Firm] dated [invoice date]

Hi [Name], a quick note that the invoice dated [invoice date] for [balance] is due on [due date]. You can pay the full balance here: [payment link]. If anything on the invoice needs explaining, reply to this email and we’ll walk you through it.

Who sends it: billing staff, from a monitored address the client can reply to.

At 30 days: assume an oversight

At 30 days past due, the likeliest explanation is that the invoice slipped. Keep the tone friendly and the ask specific.

Subject: Following up: invoice dated [invoice date]

Hi [Name], our records show [balance] still open on the invoice dated [invoice date]. It may have crossed in the mail with a payment; if so, thank you, and please ignore this. If not, you can pay the full balance here: [payment link]. Happy to resend the invoice or answer any questions.

Who sends it: billing staff. Copy the responsible attorney internally (not on the email to the client) so the attorney isn’t surprised if the client raises it on their next call.

At 60 days: be direct, and offer a path

By 60 days, an oversight is less likely. The client may be disputing something silently, waiting on their own cash, or deprioritizing you. Name the overdue balance plainly and give the client a way to respond other than silence.

Subject: Balance of [balance] on invoice dated [invoice date]

Hi [Name], the invoice dated [invoice date] remains unpaid, with a balance of [balance]. We’d like to resolve it this month. You can pay the full balance here: [payment link]. If something on the invoice is holding this up, or a payment plan would help, [Attorney name] is glad to set up a short call. Just reply with a couple of times that work.

Who sends it: billing staff, in the responsible attorney’s name or with the attorney’s approval. Offering a payment plan should be the attorney’s call, since it changes the terms of the relationship.

Our guide to reviewing accounts receivable aging reports covers how to sort the 60-day bucket by client and decide which balances need a call now.

At 90 days: the attorney calls

At 90 days, another email is unlikely to do what three didn’t. The responsible attorney (or the managing partner, if the attorney is too close to the client) picks up the phone. The goal of the call is a commitment: a payment date, a plan, or a clear dispute the firm can address.

Before the call, the attorney should reread the engagement letter. Its terms govern what the firm can do next, such as whether interest accrues, whether work can pause, and what happens to any retainer.

If the call fails, the firm has three broad options: keep working and accept the risk, negotiate a reduced balance, or withdraw. Our piece on write-downs vs. discounts covers how to record a negotiated reduction and what each choice does to your realization numbers.

Withdrawal is a last resort with real constraints. Under ABA Model Rule 1.16, a lawyer may withdraw when the client “fails substantially to fulfill an obligation to the lawyer regarding the lawyer’s services and has been given reasonable warning that the lawyer will withdraw unless the obligation is fulfilled.” The same rule requires compliance with any law requiring notice to or permission of a tribunal, and requires steps to protect the client’s interests on the way out, such as reasonable notice and time to find other counsel. If you’re heading that way, the 90-day letter may be where that “reasonable warning” happens, so the attorney should write it personally rather than send a template.

[Name], the invoice dated [invoice date] has a balance of [balance], now more than 90 days past due. You can pay the full balance here: [payment link]. I’d like to talk this week about how we resolve it. If we can’t reach an arrangement, I’ll need to discuss with you whether we can continue the engagement under its current terms.

Keep client confidences in every collection message

Overdue doesn’t loosen confidentiality. ABA Model Rule 1.6 bars revealing information relating to the representation without informed consent unless an exception applies. One exception allows disclosure “to establish a claim or defense on behalf of the lawyer in a controversy between the lawyer and the client,” and only to the extent the lawyer reasonably believes necessary. In practice, a law firm collections email needs an invoice date, a balance, and a way to pay. It never needs a description of the matter, and it shouldn’t go to a shared inbox or a third party without thought about who will read it. Each state adopts its own version of these rules, so check your jurisdiction’s before you change your process; treat this as guidance rather than legal advice.

What the aging report tells a managing partner

A reminder schedule is only as good as the list it runs against. LeanLaw’s AR aging shows which balances have moved into each aging bucket, alongside real-time reporting on collection performance, so the 60- and 90-day conversations start from the same numbers the partners see. For firms thinking about which parts of that follow-up to put on a schedule, our post on aged AR automation separates what to automate from what to watch.

The ask itself matters too. LeanLaw’s full-balance payment link lets a client pay everything outstanding from one link instead of invoice by invoice. Pursuit Legal collected $13K in past-due invoices within one month of starting to use it. You can see where the full-balance link and AR aging fit in LeanLaw’s billing workflow.

For the partners, a 90-day balance is earned work the firm hasn’t been paid for, and every week it ages adds to days to collect. If it’s never collected, it comes straight off the collection rate. Sending each reminder on schedule, from the right person, is how fewer balances get there.