When to Send an Invoice to Collections (and How to Avoid Getting There)

Send an invoice to a collection agency when it is at least 90 days past due, your own follow-up has genuinely failed, and the balance is large enough to justify the agency's 25 to 50 percent contingency fee. Before you hand it off, run a full internal escalation and send a formal demand letter, because most invoices that look like collections cases are really follow-up failures that a firmer, faster process would have resolved weeks earlier.

Handing an invoice to a third-party collector is the last step, not an early one. It recovers some cash from an account you had written off, but it costs a large share of the balance and effectively ends the customer relationship. Knowing exactly when you have reached that point, and how to avoid reaching it, protects both your cash and your customers.

The signs an invoice is a real collections case

Not every late invoice belongs in collections. A payment that is 20 days late from a customer who always pays is a follow-up job. A collections case looks different. Watch for the combination, not any single sign.

• It is 90 or more days past due, well beyond your terms and past the point where normal reminders work.
• The customer has gone silent, ignoring emails, texts and calls, or repeatedly breaking promises to pay.
• There is no live dispute. If the balance is withheld over a genuine problem, that is a dispute to resolve, not a debt to collect.
• The relationship is effectively over, so preserving goodwill is no longer a reason to keep it in-house.
• The amount justifies the cost, because a contingency fee on a small balance can leave you with very little.

When most of those are true, internal collecting has run its course and a specialist is the reasonable next move.

What sending to collections actually costs

Third-party collection agencies almost always work on contingency: they keep a percentage of what they recover and you pay nothing if they collect nothing. The rate depends heavily on the age and size of the debt.

On a $10,000 invoice at a 40 percent rate, you net $6,000, and only if the agency succeeds. That is far better than the zero you were staring at, which is the point, but it is a steep enough haircut that avoiding collections entirely is almost always the better outcome. For a fuller breakdown, see our guide to how much collection agencies charge.

The escalation ladder to run first

Before an invoice reaches an agency, it should have moved through a clear, timed sequence. Most invoices never make it past step three when the process is tight.

Before due: a reminder. A short note a few days before the due date puts the invoice on the customer's radar while there is still time to pay on time.

Day 1 to 15 late: friendly follow-up. A polite email, then a text, confirming they received the invoice and asking when payment will land. Most late payments resolve here.

Day 15 to 45: firmer and by phone. The tone shifts from reminder to request. A phone call at this stage surfaces disputes and excuses that email never does, and it signals the invoice is being tracked.

Day 45 to 75: final notice. A clear statement of the amount, the days overdue, any late fee, and the consequence of continued non-payment. This is where you get a firm commitment or a clear refusal.

Day 75 to 90: the demand letter. A formal written demand for payment by a specific date, stating that the account will be placed for collection if unpaid. A demand letter often gets a response on its own, because it makes the next step concrete. It is also the paper trail you want before handing off.

The pattern that works is consistency and escalation on a schedule, exactly the discipline in our guide to accounts receivable collections best practices. Invoices reach collections when that ladder is skipped, not when customers are uniquely difficult.

How to write the demand letter

The demand letter is the last step you control, so make it unambiguous. Keep it short and factual: identify the invoice number, the original amount and the days past due; state the total now owed including any late fee; set a firm deadline, typically 10 to 15 days; and state plainly what happens if payment is not received by then, which is that the account will be referred to a collection agency. Keep a copy and note the date sent. Skip the anger. A calm, specific demand is more effective than a threatening one, and it reads better if the matter ever goes further.

How to avoid getting there at all

The cheapest collections case is the one that never happens. Two things prevent most of them. First, credit control at the front end: decide who gets terms and how much before you ship, which is the job of a real credit policy. Second, follow-up that never lets an invoice drift to 90 days in the first place.

That second part is where most businesses lose invoices, because consistent, timed follow-up on every account is more than a busy team can sustain by hand. An collections automation agent runs the entire ladder on its own, chasing every overdue invoice across email, SMS and live phone calls on a fixed cadence and escalating as it ages. Invoices get worked at day 5 and day 20 instead of surfacing at day 95, which is precisely when they are still collectable in-house at no contingency cost. The goal is not a better collection agency; it is rarely needing one.

The bottom line

Send an invoice to collections when it is 90-plus days past due, communication has broken down, there is no legitimate dispute, and the balance justifies a 25 to 50 percent fee. Run the full escalation ladder and a formal demand letter first. Better still, tighten credit at the front and automate follow-up so invoices are chased relentlessly from day one, and the collections question rarely comes up at all.