Dunning

What is Dunning?

Dunning is the systematic process of sending escalating communications to customers who owe money for goods or services already provided. The term originates from the 17th-century English verb "to dun," meaning to persistently request payment.

In a business-to-business context, dunning encompasses the entire workflow of reminding, notifying, and escalating contact with accounts that have outstanding invoices. It isn't a single email or phone call. It's a carefully timed sequence of outreach across multiple channels designed to recover payment while preserving the customer relationship.

Dunning sits between routine billing and formal debt collection. When a customer misses a payment deadline, the collection sequence activates. If the sequence fails to recover payment after multiple attempts, the account typically moves to a third-party collections agency or legal action.

How Does the Dunning Process Work?

Most organizations follow a five-stage sequence, with each stage increasing in urgency:

Stage 1: Pre-due reminder (3–5 days before the due date). A brief, friendly notification that an invoice is approaching its deadline. This step alone prevents a significant portion of late payments caused by simple oversight.

Stage 2: First follow-up (1–7 days past due). A polite reminder that the payment deadline has passed. Include the invoice number, exact amount, and a direct payment link. The tone stays collaborative.

Stage 3: Escalation notice (15–30 days past due). A firmer communication referencing the original invoice date, prior outreach, and payment terms. Finance teams typically involve a senior contact at the customer's organization at this point.

Stage 4: Formal notice (30–60 days past due). A structured, formal letter introducing consequences: late fees, credit holds, or service suspension. Companies often send this as both an email and a physical letter for maximum impact.

Stage 5: Final demand (60–90+ days past due). The last internal attempt before escalating to a third-party collections agency, legal action, or writing off the balance. Industry data shows that once an invoice crosses 90 days past due, the chance of full collection drops below 65% [3].

Why Dunning Matters for Finance Teams

Late payments tie up working capital and distort cash flow forecasting. Atradius's 2025 Payment Practices Barometer found that 40% of B2B invoices in North America are now overdue, with 5% ultimately written off as uncollectible [1]. For a company with $10 million in annual credit sales, that 5% represents $500,000 in lost revenue before accounting for the staff time spent chasing it.

The financial impact extends beyond the unpaid amount. Every overdue invoice consumes staff time for follow-up, complicates expense reconciliation, and creates downstream issues for accounts payable teams processing vendor payments on the other side of the same transaction.

Three metrics help finance teams measure collection effectiveness:

Days Sales Outstanding (DSO): The average number of days it takes to collect payment after a sale. Target: below 45 days for most B2B businesses.

Collection Effectiveness Index (CEI): Measures how efficiently the team converts receivables to cash. A CEI of 80–90% is strong; 95%+ indicates excellent performance.

Average Days Delinquent (ADD): Isolates how many days past due invoices are on average. A consistently decreasing ADD confirms the collection sequence is working.

Best Practices for Effective Dunning

Finance teams that consistently recover more from overdue accounts follow these practices:

Automate the sequence, personalize the message. Automated collection tools maintain consistency and help ensure every overdue account receives timely outreach. Generic templates underperform personalized messages that reference the specific invoice, the customer's history, and the relationship context. The most effective approach combines automation for timing with human judgment for tone.

Segment by account value and risk. A Fortune 500 client that's three days late on a $200,000 invoice warrants a different approach than a small account that's chronically 45 days behind. High-value accounts often receive a personal call from a relationship manager alongside the automated email. Chronic late payers may move to prepayment terms after repeated collection cycles.

Align collection workflows with your expense policy. Late fees, credit holds, and service suspension are only effective when they're documented in payment terms the customer agreed to upfront. Finance teams that define consequences clearly in their terms of service are better positioned during escalation stages.

Connect AR data to accounts payable automation. When collection workflows feed into the same system that manages outgoing payments, finance teams can see both sides of the cash flow picture. Expense report automation further reduces manual reconciliation so staff time can shift from data entry to collections strategy.

When Should You Consider Alternatives to Dunning?

Payment recovery sequences work best for accounts with a willingness to pay but a timing or process issue. In several situations, other approaches serve finance teams better:

Disputes. If a customer disputes the invoice amount, service quality, or contract terms, continuing to send reminders creates friction without progress. Pause the collection sequence, route the account to dispute resolution, and resume outreach only after the dispute is settled.

Insolvency risk. When a customer shows signs of financial distress (e.g., multiple bounced payments, public bankruptcy filings), reminder emails won't recover the debt. Move directly to legal review or file a proof of claim if bankruptcy proceedings have begun.

Small-balance write-offs. For invoices below a threshold where the cost of continued collection exceeds the amount owed, writing off the balance is more efficient. Most organizations set this threshold between $50 and $500 depending on their average invoice size.

Prepayment conversion. Customers who repeatedly require payment reminders may be better served by shifting to prepayment or corporate card billing, which eliminates the receivable entirely. This protects cash flow without damaging the relationship through constant follow-up.

Related Terms

• Expense Report: The document employees submit to request reimbursement for business expenses, often the starting point for identifying internal payment delays.
• Credit Card Reconciliation: The process of matching corporate card transactions to receipts and accounting records, a related finance workflow that benefits from the same automation principles as AR collection.

Sources

[1] Atradius, "Payment Practices Barometer for North America," 2025 (as compiled by InvoPilot, "Accounts Receivable Statistics," 2026, invopilot.com/blog/accounts-receivable-statistics/) [2] Resolut AI, "A Finance Leader's Guide to Dunning Letters and AR Control," 2025. resolutai.com/blog/what-are-dunning-letters [3] MSB, "B2B Debt Recovery Rates by Industry: 2026 Benchmark Report," 2026. msbureau.com/blog/b2b-debt-recovery-rates-by-industry-2026/