Net-30 is a polite fiction.
Every business selling on credit knows this. The invoice says 30 days. The contract specifies 30 days. The purchase order confirms 30 days. Then the customer pays at 87 days, and accounts receivable treats it as normal.
This isn't isolated behavior from problem customers. It's systematic erosion of agreed payment terms across B2B commerce. Net-30 has quietly become Net-90 without renegotiation, without acknowledgment, and without consequence.
The cost to businesses: £23 billion annually in the UK alone, according to Federation of Small Businesses data. That's working capital tied up in unpaid invoices, financing costs to bridge the gap, and administrative overhead chasing what should have been automatic.
The Mechanics of Payment Term Drift
How does Net-30 become Net-90 without anyone explicitly changing the terms?
By the time payment arrives, it's 190% past the agreed term. The original contract said 30 days. The customer paid when convenient. And the supplier absorbed the cost rather than risk the relationship.
Why Suppliers Don't Enforce
The rational response to consistent late payment is enforcement: apply late fees, report to credit agencies, restrict future credit terms, or engage collections. But most suppliers don't.
Three factors suppress enforcement:
The result: suppliers signal that payment terms are negotiable through their own lack of enforcement. Customers learn that ignoring payment deadlines carries no real cost. Net-30 becomes Net-90 by default.
The Procurement Playbook
Customers aren't accidentally paying late. Many large organizations have explicit AP optimization strategies designed to maximize cash retention.
Common tactics:
None of these tactics violate the contract. They exploit normal business processes to extend payment timelines without explicitly renegotiating terms.
The Real Cost of Extended Terms
When Net-30 becomes Net-90, three costs hit simultaneously:
Add those costs together, and extended payment terms reduce effective margins by 2-4%. For businesses operating on 8-10% net margins, that's 25-50% of profit consumed by payment term drift.
Why Internal Solutions Don't Scale
The instinct is to solve this internally:
These solutions assume the problem is process inefficiency. The actual problem is leverage imbalance. The customer has something you want (payment). You have limited recourse without damaging the relationship. Internal process optimization doesn't fix that.
When External Enforcement Changes Behavior
Customers who routinely pay at Net-90 aren't irrational. They're responding to incentives. When payment delays carry no cost, delay is optimal.
External collections changes the incentive structure:
One industrial distributor with chronic Net-90 payment patterns moved to external collections for invoices past 60 days. Result: average DSO dropped from 82 days to 47 days within six months. Same customers, same products, same commercial relationships — different enforcement.
What Effective Enforcement Looks Like
Fixing payment term drift requires clear escalation protocols:
The key: Day 60 happens automatically, without internal approval required. When customers learn that 60 days triggers external collections, payment patterns change. Net-90 stops being the default.
Why This Isn't About Being Aggressive
Enforcing payment terms isn't hostile. It's honoring the original agreement.
The customer agreed to Net-30 when they signed the contract. Paying at Net-90 is unilateral contract modification. Enforcement simply holds both parties to the terms they negotiated.
Businesses that enforce consistently report better customer relationships, not worse. Customers respect clear boundaries. The suppliers who suffer relationship damage are those who enforce unpredictably — lenient for months, then suddenly aggressive when cash flow tightens.
Consistency is the difference between being difficult and being professional.
The Simple Reality
Net-30 means 30 days when both parties treat it that way. When only one party honors the terms and the other faces no consequence for ignoring them, the terms become meaningless.
If your average DSO is 75+ days and your contracts say Net-30, you don't have a collections problem. You have an enforcement problem. And internal process improvements won't fix it.
External collections isn't admitting failure. It's restoring the original agreement. Customers agreed to pay in 30 days. They should pay in 30 days. Everything else is just expensive fiction.
Sarah Lindberg
International Operations Lead
Sarah coordinates our global partner network across 160+ countries, ensuring seamless cross-border debt recovery.
