Your invoice is months past due. The polite reminders went nowhere. The demand letters got ignored. You are done chasing this client yourself and ready to hand the file to a collection agency. Before you do, you owe the client one last piece of paper: a Notice of Assignment to Collections. It is short, formal, and often produces payment on its own.
What a Notice of Assignment to Collections Actually Is
A Notice of Assignment to Collections is a written statement telling the client that you are transferring (assigning) the unpaid debt to a third-party collection agency on a specific date. It is not the same as a standard demand letter. A demand letter asks for payment. This notice tells the client the file is leaving your hands.
The notice does two jobs. It satisfies any contract clause that requires written warning before collections. It also gives the client one last clean window to pay you directly, before the debt picks up agency fees and a credit reporting trail.
Many clients who ignored every prior letter pay within a week of this one. The shift from "you and me" to "a collections company" is the part that lands.
When to Send It
Send the notice only after you have actually lined up a collection agency or made the firm decision to use one. Do not bluff. If the client calls to pay and you have not chosen an agency, you look unprepared. If they refuse to pay and you never follow through, the next letter you send carries no weight.
A typical timeline before sending:
- Invoice is at least 60 to 90 days past due
- You have sent at least one polite reminder and one firm demand letter
- You have a certified mail receipt or email read-receipt proving the client got them
- You have picked a collection agency or commercial debt collector and confirmed they will take the file
If you skipped earlier escalation steps, run through a proper collections escalation timeline first. The assignment notice is the last step, not the first.
What the Notice Must Include
A Notice of Assignment to Collections is short. It should fit on one page and cover:
- Your business name, address, and contact information at the top
- The client's legal name and address (matching the contract)
- The date
- Invoice number, original invoice date, and the exact unpaid balance
- A brief reference to prior letters, with dates sent
- A clear statement that the debt will be assigned to a collection agency on a specific date if not paid
- The final deadline (typically 7 to 10 days from the date of the notice)
- Payment instructions: how, where, and to whom
- Your signature and printed name
Keep the tone flat. No insults, no threats, no "I cannot believe you would do this." Facts, dates, and the deadline. The format does the work.
Sample Language That Works
You do not need flowery legal phrasing. A clean paragraph in the middle of the letter carries the message:
This is formal notice that the unpaid balance of $4,820 on invoice INV-2026-118, issued June 12, 2026, remains outstanding 94 days past the due date. Despite written demands sent on August 4 and September 1, 2026, no payment has been received. If payment in full is not received by October 9, 2026, this account will be assigned to a third-party collection agency on October 10, 2026. Once assigned, the debt may be reported to commercial and consumer credit bureaus and collection fees may be added to the amount owed.
Notice what is missing: no insults, no legal jargon, no promises about courtrooms. The sentences read like a statement of fact, because that is what they are.
How to Send It So It Counts
Send the notice by certified mail with return receipt requested, and send a copy by email the same day. Certified mail proves the client received it. Email gives you a timestamped record and often produces a faster response.
Keep all of this in one folder: the original invoice, prior demand letters, USPS tracking numbers and green cards, email screenshots, and a copy of this notice. If the file does go to collections, the agency will ask for it. If you end up in small claims court instead, the same folder is your evidence package.
What Happens After the Deadline
Most clients pay before the deadline. Of the ones who do not, most call to negotiate a payment plan in the final 48 hours. Both outcomes are good for you.
If the deadline passes with nothing, do exactly what the notice said you would do. Send the file to the collection agency the next business day. If you also intend to sue, file your small claims claim that same week, or send a final demand letter first if your state requires one. Credibility comes from doing what you said you would do.
Collection agencies typically take 25 to 50 percent of what they recover. That is the cost of getting paid on a file you cannot collect yourself. For balances under a few hundred dollars, small claims court is usually cheaper. For balances above the small claims limit in your state, or for clients in another state, a collection agency is often the better tool.
Getting the Notice Written Without Guessing
The hardest part of this letter is the tone: firm enough to land, neutral enough to hold up if a judge reads it later. PaperHammer drafts the notice and the two letters that should come before it, calibrated to your state's small claims limit and your specific invoice details. You fill in the job, the client, and the amount; you download three ready-to-send PDFs in about five minutes. Review and edit before you send, then mail certified.