Ask the owner of a small engineering firm what threatens the business and the answer is rarely competition or demand. It is the ninety days between delivering work and being paid for it, and the quiet certainty that a large customer will take longer than agreed and face no consequence for doing so.
Late payment is the most under-discussed structural problem in British business. It transfers working capital from firms that cannot easily borrow to firms that can, it destroys otherwise viable companies, and it has survived every attempt at reform because the incentives favouring it are strong and the enforcement is weak.
Why the practice persists
For a large company, stretching payment terms improves reported cash conversion and costs nothing. For a small supplier, chasing payment risks the relationship that sustains the business. That asymmetry is the whole story. No amount of moral suasion changes a negotiation in which one side can walk away and the other cannot.
The Small Business Commissioner was created to shift that balance through transparency and complaint handling, and has recovered meaningful sums. But the office relies substantially on reputational pressure, and reputational pressure works only on firms that consider themselves reputable.
The cash conversion arithmetic
Consider a firm with a ten per cent net margin invoicing 50,000 pounds a month. If payment slips from 30 days to 75, it must fund an extra 75,000 pounds of working capital indefinitely. That is more than a year of profit tied up in a customer balance sheet. If the bank will not fund it, the firm either declines new work or fails, and both outcomes look from the outside like a lack of ambition.
Insolvency statistics published by the Insolvency Service show creditor-driven failures clustering in sectors with long payment cycles, particularly construction and specialist manufacturing. These are not businesses with weak products. They are businesses with strong order books and no working capital.
Why construction is the extreme case
Construction combines long chains of subcontracting with retentions, a practice in which a percentage of each payment is withheld against defects and frequently never returned. A subcontractor may complete work, wait months for payment, and then wait years for the retention, occasionally losing it entirely when the tier above becomes insolvent.
Reform proposals have circulated for two decades, most involving statutory retention deposit schemes similar to those protecting tenancy deposits. Industry bodies including the Federation of Master Builders have campaigned for them consistently. The obstacle is not principle but the transitional cost to main contractors whose balance sheets already depend on the float.
What actually works
Three interventions have measurable effect. Mandatory reporting of payment performance creates a public record that procurement teams can act on. Making prompt payment a condition of eligibility for public contracts gives the state leverage that no individual supplier has. And a statutory right to interest that is automatic rather than claimable removes the need for a small firm to pick a fight.
Digital invoicing and open banking payment initiation reduce the administrative excuses, which matter more than they should. A surprising share of late payment is not strategic at all but the result of approval workflows designed in the era of posted invoices.
The advice that actually helps
Practical defences exist. Credit-check customers before the first order rather than after the first default. Invoice on milestones rather than completion. Make interest and recovery costs explicit in terms and charge them once, early, so the expectation is established. And treat concentration risk seriously: a single customer worth forty per cent of revenue is a strategic vulnerability regardless of how reliable they seem.
Why voluntary codes keep failing
Britain has tried the voluntary route for late payment for the better part of thirty years, through successive iterations of prompt payment charters, reporting duties and named commissioners. The results have been modest, and the reason is not mysterious. A voluntary code asks a large buyer to give up free working capital in favour of a supplier who has no realistic power to walk away. Reputational pressure works only where the reputation is at risk, and in most business-to-business supply chains it simply is not.
The reporting regime that requires large companies to publish payment performance was a genuine improvement, because it created a public record where none existed. But publication without consequence produces disclosure, not behaviour change. Firms have learned to report accurately while continuing to run standard terms of sixty days or longer, and to use the gap between agreed terms and actual settlement as an internal funding source.
The interventions that have actually shifted behaviour elsewhere share one feature: automatic financial consequence. Statutory interest that accrues without the supplier having to claim it, applied by default rather than on request, changes the arithmetic for the buyer without requiring the smaller party to pick a fight. So does making payment performance a hard qualifying condition for public procurement rather than a scored criterion that can be offset by price.
For a small firm reading this, the practical defences remain unglamorous but effective: invoice immediately rather than monthly, state interest terms on the face of the invoice, chase at day one rather than day thirty, and treat a customer who consistently pays late as a credit risk rather than a relationship to be preserved. Cash flow, not turnover, is what closes businesses.
