Customer has not paid an invoice on time - what should you do step by step?

If a customer has not paid an invoice on time, simply sending another request for payment is not enough. You need to establish whether the receivable is undisputed, where the payment has stalled, and whether the promised payment date is supported by the customer's internal process. At the same time, it is worth calculating how the missing inflow will affect payroll, taxes, instalments, and supplier payments.

The key is to separate two problems:

• recovering the receivable from the customer
• protecting your own liquidity until payment arrives

Financing can help with the second problem if the gap is temporary, the receivables are confirmed, and the business has identified a realistic source of repayment. It does not replace debt recovery, however, and it cannot turn a disputed invoice into a reliable inflow.

Why can a late invoice quickly become a problem for the entire business?

One overdue invoice does not always mean a crisis. It can, however, trigger a chain reaction if the business has already incurred the costs of delivering the work, has only a small cash buffer, or is heavily dependent on a single customer.

A payment bottleneck begins when one missing inflow makes it harder to pay other obligations and passes the delay on to suppliers, employees, or public authorities.

The scale of the problem is reflected in the work of the Polish Office of Competition and Consumer Protection, Urząd Ochrony Konkurencji i Konsumentów (UOKiK). In 2025, the authority issued 29 decisions concerning payment bottlenecks and imposed fines totalling more than PLN 10 million. By April 9, 2026, it had issued another eight decisions. These concerned payment bottlenecks with a combined value exceeding PLN 200 million, while the fines totalled more than PLN 2.6 million. UOKiK publishes data for 2025 and the beginning of 2026. On July 1, 2026, the authority also announced two further fines for Avon and Neptun, with a combined value of more than PLN 2.3 million, as well as 100 formal interventions addressed to businesses. See the UOKiK announcement from July 1, 2026.

These figures show the scale of systemic payment delays. From the perspective of a small business, however, what matters most is how one specific invoice will affect the next few weeks. Payroll, social security contributions, taxes, lease payments, and supplier invoices all have their own due dates. They do not move automatically just because a customer pays late.

Does one unpaid invoice already constitute a payment bottleneck?

In everyday business language, a payment bottleneck is a situation in which a delayed inflow blocks subsequent payments. Under the rules applied by UOKiK, excessive payment delays are subject to a specific threshold. For an entity other than a public entity, this threshold is reached when, over three consecutive months, the total value of due monetary obligations that were not paid or were paid late amounts to at least PLN 2 million. UOKiK explains the statutory definition of a payment bottleneck and the applicable threshold.

This means that one overdue invoice does not automatically become a UOKiK matter. It remains a due receivable that the business should monitor and recover.

In practice, it is useful to distinguish between three situations:

This distinction matters more than the number of days by which the payment is late. An invoice that is five days overdue, acknowledged by the customer and scheduled for payment, may be less risky than an invoice that is one day overdue if the customer suddenly disputes the entire service.

Step 1. Verify the basis of the receivable and remove any internal process blockers

Before assessing the customer's behaviour, make sure your own business has provided every document required by the agreement and the customer's procurement process. In a larger organisation, payment may be blocked by a missing purchase order number, an amount mismatch, an incorrect description, or a missing acceptance report. This does not remove the obligation to pay, but resolving the issue quickly helps distinguish genuine payment risk from an administrative blocker.

Check in particular:

• the seller's and buyer's details
• the bank account number and payment deadline
• whether the amount matches the agreement or purchase order
• how and when the invoice was delivered
• the acceptance report, proof of delivery, or confirmation that the service was accepted
• any complaints, deductions, or comments raised by the customer
• contractual provisions concerning payment, interest, complaints, and assignment of receivables

The result of this step should be a short, organised evidence pack: the purchase order or other basis for the work, confirmation of delivery or acceptance, a correct invoice, proof of delivery of the invoice, and a record of any objections raised. This allows the person handling the case to confirm clearly that the work was completed, the customer accepted it, the invoice is correct, and the payment deadline has passed.

Step 2. Establish the payment status, case owner, and a firm deadline

The first follow-up after the due date should not be limited to asking when the customer will pay. Its purpose is to establish exactly where the payment has stalled, who can remove the blocker, and whether the customer accepts the obligation without reservation. Only then does a promised payment date become information on which further action can be based.

In a larger organisation, the person who managed the project often has no responsibility for invoice approval or the payment run. It is therefore worth contacting both the business owner of the relationship and someone in finance or accounts payable. The conversation should answer five questions:

• Has the invoice been registered in the system and matched to the correct purchase order or agreement?
• Has it passed substantive and formal approval? If not, who needs what information or document?
• Does the customer confirm that the full amount is undisputed?
• Who is responsible for initiating the transfer and on what schedule does the company make payments?
• What is the exact date on which the transfer will be initiated, rather than an approximate week or month?

If the customer reports a missing document, determine whether it is a genuine procedural obstacle or a new objection raised only after the due date. If the customer requests an extension, ask whether the proposed date is a one-off change or part of a wider liquidity problem. This affects both the escalation route and the reliability of your own cash flow forecast.

Summarise the conversation by email. State the invoice number and amount, the confirmed status of the receivable, any outstanding actions on either side, and the date on which the transfer is to be initiated. It is also worth stating what will happen if the agreed date is missed, such as moving the case to a formal demand for payment. A new promise of payment should not restart the process or erase the escalation that has already taken place.

Step 3. Classify the delay: process issue, dispute, or payment risk

Once you have information from the customer, translate it into a management decision. A statement that payment will arrive later does not tell you whether you are dealing with a brief operational delay, a dispute that requires documentary work, or an increase in the customer's credit risk. Each scenario requires a different case owner, pace of action, and assumption in the cash flow forecast.

What matters most is not the customer's reassurance but facts that can be verified: the invoice status in the system, the name of the approver, specific objections, the customer's record of meeting deadlines, and their willingness to confirm commitments in writing. Based on this evidence, the delay can be assigned to one of three paths.

Administrative delay

The invoice has not entered the system, the responsible person has not approved it, or payments are processed only on specific days. In this situation, the priority is to remove the blocker, identify the person responsible, and obtain a confirmed payment date. If all these elements are known, the risk will usually remain operational. If the customer cannot provide them, the label "administrative issue" should not reassure the creditor by itself.

Dispute concerning the receivable

The customer raises objections concerning the scope of work, quality, acceptance, or amount. The case should no longer be treated solely as a payment delay. Establish when and in what form the objections were raised, what part of the receivable remains undisputed, and which documents confirm performance of the agreement. In this path, the priority is to resolve the dispute and preserve the evidence, not to obtain another promise about the payment date.

Customer's financial problems

The customer asks for another extension, misses previously agreed dates, avoids written commitments, or changes the explanation for the delay. These are signs that the business is no longer managing only a payment date but its exposure to customer risk. In this situation, prepare a formal escalation more quickly, review any further deliveries or work, and do not base your cash plan on the most optimistic payment date.

Step 4. Build an escalation process that actually changes the level of action

Escalation does not mean sending the same message to the same person more often. It should change at least one element of the process: the decision-making level on the customer's side, the formality of the communication, the terms of continued cooperation, or the route used to recover the receivable. If the next reminder does not change the recipient, deadline, or consequences of non-payment, it is usually not an escalation.

Internally, every overdue receivable should have an owner, an exposure value, a next action, and a decision date. The business should also define in advance the warning signs that accelerate the process, such as high concentration on one customer, a second missed promise, refusal to provide written confirmation, or information about problems affecting other suppliers.

An example process might look like this:

This is an example operational process, not a statutory timetable. If the amount is large, the customer has paid late before, or there are signs of insolvency, the response should be faster.

In commercial transactions, a creditor who has performed its obligation and has not received payment on time may be entitled to statutory interest for late payment in commercial transactions. Polish law also provides fixed compensation for recovery costs equivalent to EUR 40, EUR 70, or EUR 100, depending on the value of the monetary obligation. The Polish government portal Biznes.gov.pl explains the rules concerning payment deadlines, interest, and compensation. Before calculating any amount or taking further action, check the current rate and match the action to the specific agreement and facts of the case.

Step 5. Calculate the impact of the delay on cash flow before the business runs short of cash

Once the risk attached to the receivable has been classified, translate it into cash scenarios for the business. It is not enough to know how much is overdue. Management needs to know in which week the shortfall will arise, its maximum value, and which payments will be at risk. An 8 to 13 week forecast, preferably prepared weekly, is designed for this purpose.

Include:

• the available cash balance
• confirmed inflows and their realistic dates
• invoices that are approaching their due date but have not been confirmed for payment
• payroll, social security contributions, taxes, and instalments
• critical supplier payments
• the minimum operating buffer
• scenarios in which the late-paying customer pays one week, two weeks, or one month later

Do not include the overdue invoice in the forecast solely on the basis of a promise made by phone. If the date has not been confirmed or the customer has already missed it once, prepare a more cautious scenario. We explain the difference between accounting performance and available cash in more detail in Cash Flow vs Profit - Why Your Business Looks Profitable on Paper but Has No Cash.

Step 6. Separate recovery of the receivable from financing the liquidity gap

Debt recovery and financing answer two different questions. Debt recovery asks: how can the business recover the money from the customer? Financing asks: how can the business cover justified expenses before the expected funds arrive?

One does not replace the other. If the receivable is disputed or there is a high risk that the customer will not pay, additional financing may only increase the business's liabilities. In that case, first assess the chances of recovering the money and limit any further exposure to that customer.

Financing may make sense when:

• the business is profitable and the problem results from a timing mismatch
• there are other confirmed receivables or contracts that can provide a source of repayment
• the value and duration of the gap have been calculated
• the financing cost fits within the business's margin or budget
• the repayment schedule matches a cautious inflow scenario

Financing should not conceal a situation in which:

• the customer disputes the service or the invoice itself
• the business has no credible source of repayment other than this one uncertain receivable
• cash flow will remain negative in the following months
• the margin on the job does not cover the cost of capital
• the business regularly finances losses rather than a temporary timing mismatch

Can factoring help if the invoice is already overdue?

Do not assume that it can. Factoring most often applies to confirmed invoices with deferred payment terms before they become overdue. The finance provider assesses both the business and the customer, as well as payment history, documents, and whether the receivable can be assigned.

If the customer has already failed to pay, avoids contact, or disputes the receivable, the invoice may not qualify for financing. In addition, recourse factoring does not eliminate the risk of non-payment. If the customer does not settle the invoice, the business may be required to repay the advance in accordance with the agreement.

A sensible scenario may look different. One late invoice creates a gap, but the business also has other undisputed invoices due from reliable customers in 30 to 60 days. Financing one of these healthy receivables can accelerate the inflow and protect current expenditure. It does not fix the overdue invoice, but it helps manage the consequences of the delay.

Example: one overdue invoice and a PLN 48,000 gap

A service business issued an invoice for PLN 120,000 net to a key customer. The due date has passed, and the customer has confirmed that payment will be delayed by at least two weeks.

Over the next 14 days, the business must pay:

• PLN 55,000 in payroll
• PLN 30,000 to subcontractors
• PLN 18,000 in taxes and instalments
• PLN 20,000 in other operating costs

Total expenditure is PLN 123,000. The business has PLN 35,000 in its bank account and PLN 40,000 in other confirmed inflows. It is short by PLN 48,000.

The first mistake would be to assume that the customer will certainly pay in two weeks even though the original due date has already been missed. The second would be to finance the entire PLN 120,000 without checking how much the business actually needs.

The business should:

1. Confirm the new payment date in writing and continue recovering the receivable.
2. Prepare a scenario in which the transfer arrives only after 30 days.
3. Check which expenses are critical and which can be safely postponed or rescheduled.
4. Assess other undisputed receivables. Assume that the business has a net invoice for PLN 80,000 due from a reliable customer in 45 days.
5. Compare the cost of accelerating this healthy receivable with the cost and consequences of a cash shortage.

In this example, the purpose of financing is not to rescue the uncertain PLN 120,000 invoice. It is to close the calculated PLN 48,000 gap using a receivable whose quality and payment date can be assessed reliably.

You can find more criteria for making a prudent decision in When Does Non-Bank Business Financing Make Sense, and When Is It Better to Avoid It?.

Step 7. Reduce the risk of future payment delays

Every material overdue payment should be used as a test of the business's commercial policy and receivables process. Once the current case has been resolved, determine whether the exposure resulted from a failure to verify the customer, an excessive credit limit, an unfavourable payment schedule, delayed invoicing, or the absence of an automatic escalation process. The conclusions should affect the terms of future agreements and the way the entire receivables portfolio is managed, not just the relationship with one customer.

Verify the customer and set an exposure limit

Before accepting a large order, review the customer, the history of the relationship, and the share of this customer's receivables in the entire portfolio. Set a limit on the amount that can remain outstanding before the business stops further delivery.

Use advance payments and milestone billing

If a project requires materials, subcontractors, or several months of work, one payment at the end shifts a large share of the risk to the contractor. An advance and milestone payments align inflows more closely with costs.

Issue invoices without delay

Every day between acceptance of the work and issue of the invoice extends the wait for payment. The agreement should also define clearly which documents are required for acceptance and when the payment period begins.

Automate reminders and status tracking

The process should not depend on one person's memory. A reminder before the due date, a message on the due date, and an escalation after the deadline reduce the risk that an invoice will go unnoticed for two weeks.

When should a business notify UOKiK about payment bottlenecks?

Anyone can notify UOKiK of suspected excessive delays in the performance of monetary obligations. The notification should identify the business, describe the situation, and provide reasonable grounds for believing that the problem is broader in scope. The identity of the person submitting the notification and its contents are not disclosed. UOKiK explains the available methods for submitting a notification.

Two points are important:

• UOKiK initiates payment bottleneck proceedings on its own authority
• a notification does not replace recovery of a specific receivable from the customer

UOKiK investigates systemic excessive payment delays and may impose a fine on the business concerned. If the objective is to recover your own invoice, you still need a separate process involving direct contact, a demand for payment, and potentially further legal recovery action.

Summary - manage the receivable and liquidity in parallel

When a customer does not pay an invoice on time, the worst response is to wait indefinitely. Check the documents, establish the cause, obtain a specific payment date, and plan the escalation. At the same time, calculate the impact of the delay over the coming weeks so that a payment bottleneck does not pass the customer's problem on to your employees, suppliers, and public authorities.

Financing can be a sensible tool if the gap is temporary and supported by reliable receivables or contracts. It should not, however, replace debt recovery or rely solely on the hope that a disputed invoice will be paid.

The simplest rule is this: recover the receivable separately and protect liquidity separately. Both decisions should be based on documents, dates, and a cautious scenario, not merely on a promise of payment.