---
title: "Past due: definition | Rex glossary"
description: "An invoice that hasn't been paid by its due date. It stays past due, and keeps aging, until it's paid, credited or written off."
canonical: https://www.rex.inc/glossary/past-due
---

# Past due

Also called Overdue

An invoice that hasn't been paid by its due date. It stays past due, and keeps aging, until it's paid, credited or written off.

Past-due balances are usually grouped by how late they are: 1–30, 31–60, 61–90 and more than 90 days past due. The older the balance, the lower the chance of collecting it in full.

Not every past-due invoice is a collections problem. Many are waiting on something else, such as a missing PO, a portal rejection or an open dispute, and won't be paid until that's fixed.

How Rex helps

Collections

Agents follow-up with every customer, 24/7.

[See how it works](https://www.rex.inc/collections)

## Further reading

- [How to collect overdue invoices: templates, timing, and escalation→](https://www.rex.inc/resources/guides/how-to-collect-overdue-invoices)

## Related terms

- [AR aging Grouping open receivables by how long they've been outstanding, to show how much is current and how much is late.](https://www.rex.inc/resources/glossary/accounts-receivable-aging)
- [Delinquent account A customer account with invoices significantly past due, usually flagged for closer follow-up, a credit hold or escalation.](https://www.rex.inc/glossary/delinquent-account)
- [Dunning The structured sequence of reminders sent as invoices approach and pass their due date, escalating in tone and channel.](https://www.rex.inc/resources/glossary/what-is-dunning)

Next step

Accelerate your receivables operation with Rex

A short walkthrough of agents working your accounts under your guardrails, with your team on the exceptions.

[Learn more](https://www.rex.inc/learn-more)

[Back to the glossary](https://www.rex.inc/glossary)