What is a collection agency and how do they work?

A collection agency is a company that recovers overdue debts on behalf of another business. When a customer stops paying and your own follow-up has run its course, you hand the account to an agency, and it pursues the money for a fee or a cut of what it collects.

Agencies exist because chasing a small number of seriously delinquent accounts is slow, specialized work. For most businesses it is cheaper to outsource the hardest cases than to staff for them. But an agency is the last and most expensive stop in collections, so the goal is to send as few accounts there as possible.

How collection agencies work

You place an account by sending the agency the customer details, the invoice, and the proof the debt is valid. The agency then works the account through its own cadence of calls, letters, and emails, usually firmer than your own, and often referencing the consequences of continued non-payment.

When the customer pays, the agency keeps its fee and remits the rest to you. If contact fails, some agencies escalate to legal collections, where an attorney files suit to win a judgment. Reputable agencies work under debt-collection rules that govern how and when they can contact a debtor, which matters more in consumer collections than in business-to-business, but still shapes the process.

The key thing to understand is timing. An agency placed at 120 days past due is working a cold, stale debt. Recovery rates fall fast the longer an invoice sits, which is why what happens in the first 60 days decides how much ever reaches an agency at all.

Agencies also specialize. Some focus on early-stage commercial debt and behave more like an outsourced collections desk. Others handle older, harder accounts and lean on legal pressure. Matching the agency to the age and size of the debt matters: sending a 200 invoice to a litigation-heavy firm wastes money, while sending a six-figure judgment-worthy account to a soft early-stage shop leaves recovery on the table.

First-party vs third-party collections

First-party collections are the ones you run yourself, under your own name, while the relationship is still intact. Your team sends reminders, makes calls, and negotiates directly. This is where most cash gets recovered, because the customer still sees you as a supplier they want to keep.

Third-party collections start when you give up direct control and pass the debt to an outside agency. The customer now hears from a stranger, the tone hardens, and the relationship usually does not survive. Third-party work recovers a smaller share of each dollar and costs you part of what comes back.

Some agencies offer a middle option, working accounts in your name as an extension of your team before any formal third-party placement. That keeps the relationship softer while still bringing in outside effort.

The practical line between the two is control and tone. In first-party collections you decide the cadence, the wording, and when to ease off for a good customer. Once an account goes third-party, that judgment leaves your hands, and the agency works to recover cash, not to preserve a future order. That trade-off is why placement should be a deliberate decision, not a default for any invoice that drifts past due.

What a collection agency costs

Most agencies work on contingency, keeping a percentage of what they recover and charging nothing if they collect nothing. Typical rates run from 20% to 50%, and they climb as the debt ages, because older debt is harder to collect. A 90-day account might cost 25%, while a year-old one can cost half.

Early-stage or high-volume work is sometimes priced as a flat fee per account instead. Legal collections add court filing fees and attorney costs, which you may not recover even if you win. On a 10,000 invoice placed at a 35% contingency rate, you net 6,500 at best, and only if the agency collects in full.

That fee is the real cost of letting an account age. Every dollar recovered in-house is a dollar you keep, and every account you collect before placement is a contingency fee you never pay.

How to reduce your reliance on agencies

The accounts that reach an agency almost always share a history: a missed early reminder, a slow response to the first overdue notice, a promise to pay that nobody tracked. Fix the early stage and the pipeline to collections shrinks.

Three habits do most of the work. Contact every invoice the moment it ages, not when someone gets to it. Escalate tone on a fixed schedule so no account drifts. And track every dispute and promise to pay so commitments convert instead of slipping into silence. Accounts worked consistently in the first 60 days rarely need an agency at all.

How Rex keeps accounts out of collections

Rex is an autonomous AR agent that works every invoice the moment it ages, across your whole ledger, without waiting for a person to get to it. It sends the right reminder at the right time, escalates tone as an invoice gets older, and follows up on every promise to pay. The accounts that usually drift to 120 days past due get worked steadily from day one, so far fewer ever go cold.

When a case genuinely needs a human, a dispute, a payment-plan negotiation, or a decision to place with an agency, Rex escalates it with the full history attached. You spend your judgment on the handful of accounts that need it, not on the busywork that lets the rest slip.

See how Rex runs collections end to end before an account ever reaches an agency.