The Chain Reaction Clause: Why 'Paid When Paid' Is a Cash-Flow Risk You Must Price

A pay-when-paid clause is often presented as a fair way to align a supply chain. In practice, it is a credit decision dressed as a payment term. The supplier does the work, incurs the cost and waits not for a date but for an event: the client receiving money from someone else. That is a very different bargain from payment on an agreed day.

The directory's view is that pay-when-paid terms should be treated as a risk transfer mechanism, not a routine administrative provision. They shift the risk of upstream non-payment or late payment down the chain to the party with the least visibility and usually the least bargaining power. For a UK supplier, the question is not simply whether the clause is lawful. It is whether you can afford to finance the client's customer.

What the clause actually does

A standard payment term says money is due on a specified date or after a specified period. A pay-when-paid term says money is due only if and when the payer receives funds from its own customer. The trigger is receipt, not performance. If the upstream payment is delayed, disputed or never made, the supplier may wait indefinitely unless the contract contains a long-stop date, a notice obligation or some other protection.

The confusion arises because pay-when-paid is sometimes confused with pay-when-certified. Certification can also delay payment, but at least it is a process the client controls and can be required to operate within a timetable. Pay-when-paid is different: it makes the supplier's cash flow dependent on a contract it has never seen and a customer it may not be able to chase.

The wording to look for

Pay-when-paid clauses are not always labelled as such. The warning signs include phrases such as 'payment shall become due only upon receipt by the client of payment from the employer', 'no payment shall be made until funds have cleared from the end customer', 'payment is conditional upon the client being paid' and 'the supplier acknowledges that payment is back-to-back with the main contract'. A clause may also say that the client has no liability until it has been funded, or that the supplier bears the risk of upstream default.

Look beyond the payment clause itself. Check the definitions of 'payment', 'due date' and 'invoice'. Check whether the client has any duty to pursue the upstream debt, to tell you if it has not been paid, or to provide evidence. Check whether you have a right to suspend work or terminate if payment does not arrive. A pay-when-paid clause with no long-stop date and no information obligation is not a payment mechanism; it is an open-ended credit line.

Why it pushes risk down the chain

Every tier in a supply chain has its own margin, overheads and creditors. When payment risk is passed downwards, the smallest supplier often ends up carrying the largest relative burden. That supplier may still have to pay wages, VAT and material costs while waiting for a payment that is conditional on a contract it cannot control. The result is not just inconvenience. It can mean borrowing, delayed payments to sub-suppliers and, in the worst cases, insolvency.

The clause does not create money or resolve the upstream dispute. It simply allocates the delay. If the end customer is a slow payer, pay-when-paid turns that slow payment into a supply-chain problem. The client keeps the benefit of the work while the supplier carries the funding cost.

The UK legal backdrop

In construction contracts, pay-when-paid provisions are generally void under section 113 of the Housing Grants, Construction and Regeneration Act 1996, subject to a limited insolvency exception. That statutory protection is well known in the construction sector, but it does not cover every commercial contract. Outside construction, there is no general prohibition on pay-when-paid wording. General contract law and late payment legislation may still apply, but they do not automatically strike out a clause that makes payment conditional on a third party paying.

This is why the wording matters. A supplier should not assume that because a clause feels unfair it will be unenforceable. Nor should a supplier assume that a statutory right to interest solves the problem. Interest may compensate for late payment once a sum is due, but it does not necessarily create a due date where the contract makes payment conditional on an upstream receipt.

Negotiation scripts that move the conversation

A blunt refusal can end a negotiation. A structured alternative is more likely to work. The aim is to replace an open-ended condition with a defined payment event, a long-stop date or a risk-sharing mechanism.

'We understand that you want to align our payment with your own customer. We can accept a defined period after your certification, but we cannot accept payment being conditional on your receipt of funds. Can we amend the clause so that payment falls due no later than 30 days after certification, whatever happens upstream?'

'If the concern is your own cash flow while you wait for the end customer, we can discuss stage payments or a parent company guarantee. What we cannot do is leave the payment date open-ended.'

'We can accept a notice obligation. If you have not been paid, you must tell us within five working days and provide evidence of the upstream position. After 60 days from our invoice, the amount becomes payable regardless.'

'Our price assumes payment within 30 days of invoice. If the payment date depends on your customer, we will need to price the additional financing cost or move to milestone billing.'

Fallback positions

If the client will not remove the clause, consider a long-stop date. This is the single most useful protection: a fixed date on which payment becomes due whether or not the upstream money has arrived. Add a notice obligation so the supplier knows where it stands. Require evidence of the upstream payment position. Ask for a parent guarantee or a retention mechanism where the risk is material. Preserve a right to suspend work or terminate for non-payment. If the risk remains substantial, reflect it in the price, reduce the credit limit or require payment for each stage before the next begins.

Warning signs that the clause is doing too much work

The strongest warning sign is resistance to a long-stop date. If a client says it wants 'alignment' but refuses a fixed backstop, the clause is not about timing; it is about keeping an open-ended option to delay. Other red flags include no obligation to chase the upstream debt, no duty to provide information, no right to audit the payment position, a confidentiality clause that prevents you from seeing the upstream terms and a purchase order that incorporates pay-when-paid wording by reference. Be wary of a client that cannot explain in plain English when payment becomes due.

A pay-when-paid clause is a commercial risk. It may be acceptable if it is bounded, evidenced and priced. It should not be accepted simply because it appears in the standard terms. Before you sign, decide whether you are supplying goods or services, or lending working capital to a business you cannot see. If it is the latter, the price and the terms should say so.