A $40,000 invoice that is paid 60 days late is not just an overdue invoice. It is $40,000 of working capital sitting somewhere else while the business that earned it waits. For a finance team managing 100 or 1,000 invoices, those delays become a cash flow problem very fast.

That is where dunning comes in.

Dunning is the process businesses use to follow up on unpaid invoices, from pre-due reminders to overdue collections, payment commitments and escalation. But effective dunning is not about sending the most reminders possible. It is about knowing when to chase, when to stop and what should happen next when a customer has responded, disputed an invoice or promised to pay.

In this guide, we explain what dunning is, how the collections process works, the difference between manual and automated dunning and how businesses can build a process that helps move cash forward without turning every customer interaction into a chase.

How Does the Dunning Process Work?

The dunning process usually begins before an invoice becomes overdue and continues until the payment is received, matched and the outstanding balance is closed. The exact cadence varies by business, customer and payment terms but most dunning processes contain the same core stages.

1. The Invoice Is Issued

Dunning starts with a clear record of what is owed, who owes it and when payment is expected. The invoice amount, due date, payment terms and payment instructions create the foundation for everything that follows. If the invoice contains an error, missing purchase order or unclear information, payment may be delayed before the collections process has even started.

2. Pre-Due Reminders Create An Opportunity To Pay

A payment reminder before the due date gives the customer a chance to act without the interaction feeling like a collections escalation. For businesses with Net 15, Net 30, Net 45 or Net 60 terms, pre-due communication can help keep upcoming obligations visible and surface questions before the invoice becomes overdue.

3. The Due Date Creates A Decision Point

When the due date arrives, the business needs to know whether the invoice has been paid, is being processed or requires follow-up. A reminder at this stage can be useful, but it should not assume that every unpaid invoice has the same story. The customer may have paid through a method that has not yet been reconciled, or the invoice may be waiting for internal approval.

4. Overdue Invoices Enter The Collections Process

Once an invoice is overdue, the business needs to decide what happens next. Some customers may simply need a reminder. Others may have a genuine blocker. The longer an invoice remains unpaid, the more important it becomes to understand the reason behind the delay and assign the right next action.

5. The Customer Responds, Disputes or Makes A Commitment

This is where a basic reminder sequence often stops being enough. The customer may say that the amount is incorrect, confirm that payment will be made on Friday or explain that the invoice is waiting for approval. Each response changes the situation. A promise to pay creates a commitment with its own date. A dispute creates a resolution process. A payment confirmation may mean that chasing should stop while the payment is verified.

6. The Process Escalates When Judgement Is Needed

Not every collection action should be automated. A high-value overdue invoice, unresolved dispute or missed promise to pay may need a finance team member, account owner or senior stakeholder to review the situation. Effective dunning automation should create a clear handoff instead of continuing to send increasingly aggressive messages forever.

7. Payment Is Received and The Invoice Is Closed

The collection process does not end when money arrives. The payment needs to be identified, matched to the correct invoice and recorded. Remittance information, payment evidence, partial payments, adjustments and write-offs may need to be reviewed before the invoice is fully settled.

What is a Dunning Schedule?

A dunning schedule is a planned sequence of reminders and collection actions based on an invoice's lifecycle. A business might send a reminder seven days before the due date, another on the due date, and follow up at defined intervals after the invoice becomes overdue.

The schedule provides consistency. Without one, follow-up often depends on memory. One customer receives several reminders because someone is actively watching the account, while another invoice is forgotten because it is buried in a spreadsheet or inbox.

However, a dunning schedule should not be treated as an instruction to send a message regardless of what has happened since the last action. A customer who has promised to pay on Friday should not receive the same generic reminder on Thursday. An invoice under dispute should not continue through the same sequence as an invoice that has simply been overlooked.

Dunning and Collections: What is The Difference?

Dunning and collections are closely connected, but dunning is usually one part of the wider accounts receivable collections process. Dunning generally refers to communicating with customers about unpaid invoices. Collections can include those reminders, but also dispute resolution, promise-to-pay tracking, escalation, payment evidence, reconciliation and recovery activity.

A payment reminder answers one question: has the customer been asked to pay? A complete collections process asks much more. Why is the invoice unpaid? Has the customer responded? Is there a dispute? Has a payment date been promised? Who owns the next action? Has the cash arrived but not yet been matched?

The distinction is important because sending a reminder is only one possible action. Sometimes the right next step is to resolve an invoice error. Sometimes it is to follow up on a missed commitment. Sometimes it is to stop chasing because payment is already being verified.

Why Do Businesses Use Dunning?

Businesses use dunning to create a consistent way to follow up on outstanding invoices. The alternative is often a collection process spread across individual inboxes, spreadsheets, accounting systems and personal memory. That makes it difficult to know which invoices have been contacted, what customers have said and what should happen next.

A structured dunning process helps finance teams create a reliable cadence without requiring someone to manually remember every follow-up. It can also surface problems earlier. A customer who cannot pay because of a dispute needs a different response from a customer who simply missed the invoice. A missed promise to pay needs a different action from an invoice awaiting payment verification.

The value of dunning is therefore not just the reminder itself. It is the visibility and consistency around the outstanding invoice.

The Problem With Basic Automated Dunning

Basic automated dunning usually works from a calendar. The invoice reaches a certain date, so the system sends a reminder. This solves a real problem: someone no longer has to remember to send the message.

But the harder question is what happens when the invoice changes.

A customer replies and says payment will be made next Friday. The invoice is now no longer a simple overdue invoice. A customer raises a dispute. The next step is resolution, not another generic chase. A payment arrives and is being verified. Sending another reminder at that point creates confusion rather than progress.

This is why the most useful automation is not necessarily the automation that sends the most reminders. It is the automation that understands when the next action needs to change. A strong process should ask more than, "Is this invoice overdue?' It should also ask, 'What has happened since the last action and what should happen now?."

When Should A Dunning Sequence Stop?

A dunning sequence should stop, pause or change when the context around the invoice changes. Common examples include a customer response, a promise to pay, an open dispute, payment confirmation or a human taking ownership of the next action.

This is important for customer relationships. The reminders that create the most friction are often not the reminders themselves. They are the reminders that arrive after the customer has already explained the situation. A customer who has said, "We will pay on Friday" should not need to explain the same thing again because an automated workflow ignored the conversation.

The principle is: the collection process should follow the state of the invoice, not blindly follow the calendar.

How Dunning Affects Customer Relationships

Collections communication can feel uncomfortable for both sides. The business is asking for money that is already owed, while the customer may be dealing with internal approvals, cash flow pressure, an invoice error or a genuine disagreement about what is due.

A clear dunning process can actually make that interaction easier. A professional reminder gives the customer a straightforward opportunity to pay or explain what is blocking payment. It also means the business does not need to rely on a founder or account manager personally chasing every invoice.

The important part is knowing when to move from chasing to resolution. A customer with a genuine dispute needs an answer. A customer who has made a payment commitment needs a commitment follow-up. A customer who has already paid needs payment verification. Treating all three situations as overdue invoices creates unnecessary friction.

What Should A Dunning Process Track?

A useful dunning process needs to preserve the story of the invoice. The date a reminder was sent is important, but it is only one part of the record. Finance teams also need to understand what the customer said, what was promised and what is blocking payment.

• Invoice amount, due date and payment terms.
• Payment reminders and collection communications.
• Customer responses and conversations.
• Promises to pay, including the committed date and amount.
• Disputes, reasons and resolution activity.
• Payment evidence and remittance information.
• Payments received and remaining balances.
• Adjustments, write-offs or other settlement activity.
• The owner and next action for the invoice.

Keeping this history together is also important when an account needs to be escalated. A finance team may need to understand what was communicated, when it was communicated and how the customer responded. That information should not depend on finding an old email thread or asking one person to remember what happened.

Manual Dunning vs Automated Dunning

Manual dunning gives finance teams flexibility but it requires people to review outstanding invoices, decide who needs attention and send the right communication. As invoice volume grows, this becomes difficult to manage consistently.

Automated dunning reduces repetitive work by triggering reminders and follow-up actions based on timing or invoice status. It can create a more consistent process and reduce the risk of forgotten invoices. The limitation is that poorly designed automation can become too rigid, continuing to chase customers after they have already responded or made a payment commitment.

For most businesses, the strongest approach uses both. Automation handles predictable, repetitive work. People handle judgement, disputes, important relationships and situations where the next action cannot be determined by a simple date.

How To Build An Effective Dunning Process

Here's how you can build an effective dunning process:

Start Before The Invoice Is Overdue

Use clear payment terms and consider pre-due reminders. The earlier a customer can identify a question or payment blocker, the less likely it is to become an overdue invoice.

Define The Collection Stages

Set out what happens before the due date, on the due date, after the invoice becomes overdue and when a promise to pay is missed. A defined process creates consistency.

Create Stopping Rules

Decide which events pause or stop automated chasing. Customer responses, disputes, promises to pay and payment verification should change the next action.

Track Promises To Pay As Commitments

A promise to pay has an amount, a date and an expected outcome. Treating it as a first-class commitment makes missed promises easier to identify.

Use Human Escalation Points

Automation should handle repetitive communication, but it should also know when to create a task for a person. The aim is not to automate judgement.

Keep The Invoice History Together

When conversations, disputes, commitments, reminders and payment activity stay connected to the invoice, the finance team spends less time searching for context.

Close The Loop

Match received payments to invoices and record the outcome. A collection process is complete when the cash is accounted for, not just when a reminder has been sent.

Dunning Metrics To Monitor

The right metrics depend on the business model, customer base and payment terms. The common metrics used to understand dunning and accounts receivable performance include DSO, average days to payment, percentage of invoices paid on time, overdue receivables, aging by customer, collection effectiveness, promise-to-pay fulfilment and dispute resolution time.

The purpose of these metrics is not to create another report. They should help finance teams understand why cash is delayed. If DSO is increasing, the useful question is not only how much is overdue. It is whether disputes, approvals, missed commitments, ineffective follow-up or another recurring blocker cause the delay.

Conclusion

Dunning is often reduced to a series of payment reminders. The most effective dunning process is consistent without being robotic. It creates a clear path from invoice issued to payment received, while giving finance teams visibility into what is blocking cash and what action is needed next.

As an accounts receivable workspace built for the invoice-to-cash process, Bruvora Receivables keeps invoices, customer conversations, reminders, commitments, disputes, payment evidence and settlement activity connected around the invoice. The result is a collections process that can automate repetitive follow-up, recognise when chasing should stop and bring a person into the process when judgement is needed.

Because getting paid should not depend on another reminder sitting in someone's inbox. It should be a process the finance team can see, understand and move forward.

Start a free trialor book a 15-minute walkthrough directly with the founder to see how Bruvora Receivables fits your current dunning process.