Collection Letter Templates: What to Send at 30, 60 and 90 Days Past Due

A collection letter is a written demand for a past-due invoice, sent in an escalating series as the balance ages. The standard sequence has four stages: a friendly reminder around the due date, a firmer notice at 30 days past due, an urgent letter at 60 days, and a final demand at 90 days that warns of the next step. Each letter should state the invoice number and amount, the days overdue, a clear pay-by date, and one specific action. Below are ready-to-use templates for all four stages.

By the time you are writing a collection letter, the polite reminders have not worked and the invoice is genuinely late. The letter's job is to move the balance up the client's payment queue without torching the relationship, so tone matters as much as content. Early letters stay warm and assume an oversight. Later ones get short, factual and firm, and spell out consequences. What follows is the full four-stage sequence with a template for each, plus the rules that make them actually get paid.

The 4 stages of a collection letter sequence

Most effective collections cadences move through four escalating letters, each tied to how far past due the invoice is. Send them on a fixed schedule rather than when you happen to remember, because consistency is what signals to a slow payer that this invoice will not be forgotten.

• Stage 1, due date to 15 days: a friendly reminder that assumes the invoice was simply missed.
• Stage 2, 30 days past due: a firmer notice that the account is now overdue and needs attention.
• Stage 3, 60 days past due: an urgent letter that raises the stakes and asks for immediate payment or a commitment.
• Stage 4, 90 days past due: a final demand that states what happens next if payment is not received by a hard deadline.

Stage 1: friendly payment reminder (due date to 15 days)

The first letter assumes good faith. Most late payments at this stage really are an oversight, a missed email or an invoice stuck in the client's approval workflow, so a warm nudge clears a large share of them without any friction.

Subject: Invoice #1042 from [Your Company] is now due

Hi [Name],

Just a quick note that invoice #1042 for $4,800, dated [date], was due on [date]. If it is already on its way, thank you and please disregard this. If not, you can pay using the link below. Happy to resend the invoice or answer any questions.

[Pay link]

Thanks,
[Your name]

Stage 2: firm overdue notice (30 days past due)

At 30 days the tone shifts from reminder to notice. Name the problem plainly, restate the amount and the original due date, and ask for a specific action: payment by a date, or a reason it has not been paid.

Subject: Overdue: Invoice #1042, now 30 days past due

Hi [Name],

Our records show invoice #1042 for $4,800 is now 30 days past due. We have not received payment or heard back on our earlier reminder. Please arrange payment by [date], or reply to let me know if there is a problem with the invoice we should resolve. If you have already paid, send me the payment details so I can match it and close this out.

[Pay link]

Regards,
[Your name]

Stage 3: urgent demand (60 days past due)

At 60 days the odds of collecting start to drop, so this letter gets shorter and more direct. Reference the prior notices, make clear the account is seriously delinquent, and ask for either immediate payment or a firm promise-to-pay date you will hold them to. This is also the point to mention any late fees your terms allow.

Subject: Second notice, Invoice #1042 is 60 days past due

Hi [Name],

Invoice #1042 for $4,800 is now 60 days past due, despite our earlier reminders on [dates]. This balance needs to be resolved. Please pay in full by [date], or call me directly to arrange a payment date. Under our agreed terms, a late fee of [amount or percent] now applies to the outstanding balance. I would much rather settle this with you directly than escalate it further.

[Pay link]

[Your name], [phone]

Stage 4: final demand letter (90 days past due)

The final letter is a formal demand. It is factual, unemotional and specific about consequences: a hard deadline, and exactly what you will do if it passes, whether that is suspending service, sending the account to a collection agency, or pursuing the debt in small claims. Do not bluff. Only state a next step you are actually willing to take, because your credibility on the next slow payer depends on it.

Subject: Final demand for payment, Invoice #1042

[Name],

This is a formal demand for payment of invoice #1042, dated [date], in the amount of $4,800, which is now 90 days past due. We have contacted you on [dates] without resolution.

Payment in full must be received by [date, typically 10 days out]. If we do not receive payment or a written agreement by that date, we will [refer this account to a collection agency / suspend further work / pursue the balance through small claims court], and you may be responsible for additional collection costs.

To avoid this, pay the balance in full or contact me directly at [phone] before [date].

[Your name], [title], [company]

What every collection letter needs

Whatever the stage, a letter that gets paid contains the same core elements. Leave any of them out and you give the client a reason to sit on it.

• The specific invoice: number, amount, and original due date, so there is no ambiguity about which balance you mean.
• Days past due: stated plainly, because the number itself creates urgency.
• One clear action and deadline: pay by a date, or call by a date. One ask, not three.
• An easy way to pay: a live pay link in every letter removes the "I will get to it" excuse.
• A record of prior contact: from stage 2 on, referencing earlier notices shows this is a pattern, not a one-off.

Collection letter vs dunning letter vs demand letter

These terms overlap and often get used interchangeably. A dunning letter is simply the accounting term for any letter in a scheduled collections series, so the four stages above are your dunning sequence. A demand letter usually refers to the final, formal letter, sometimes drafted or sent by an attorney, that precedes legal action. For the accounting context behind the sequence, our explainer on what dunning is and how it works covers the terminology and the mechanics.

Letters are the floor, not the ceiling

Letters work, but only if they go out reliably on every overdue invoice, in the right order, on time. That is exactly where manual collections breaks down: a busy team sends stage-one reminders on the accounts they notice and never gets to the rest, so half the aging report never receives a stage-two or stage-three letter at all. Email reminders also get ignored more than any other channel, which is why the strongest cadences add a text and a phone call as the balance ages. Our guide to writing invoice reminder emails covers the earlier, softer end of that sequence.

Running the whole sequence, every letter on every invoice on schedule and escalating to SMS and a live call when a letter goes unanswered, is more than a person can keep up by hand across a full ledger. That is the case for dunning management software that sends the entire escalation automatically, and for a full collections automation agent that does not stop at the letter. When a customer's late payment is really a dispute, remember that they are routing your invoice through their own accounts payable process, and a letter that names the exact invoice and PO clears their queue faster than a generic demand.

When the letters run out

If a well-run four-stage sequence does not produce payment or a credible commitment by 90 to 120 days, the account has told you what it is, and hoping for a fifth letter to work is how a collectible invoice becomes a write-off. At that point the decision is whether to send a formal demand, hand it to a collection agency, or pursue it in small claims. Our guide to when to send an invoice to collections walks through that call and the escalation ladder that leads to it.

The bottom line

A collection letter sequence is four escalating notices tied to invoice age: a friendly reminder, a firm 30-day notice, an urgent 60-day demand, and a formal 90-day final demand. Keep every letter specific about the invoice, the days overdue, one action and a deadline, and make it effortless to pay. The templates matter less than the discipline of sending them on time, every time, on every overdue account, which is the part that consistently gets balances paid before they go cold.