Amex Trendex Reveals the Impact of Payment Inefficiencies on Supplier-Buyer Relationships

Companies spend enormous amounts of time measuring vendor performance but often overlook one of the most important signals they send to vendors. That signal is how accurately and predictably businesses pay their invoices.

Yet payment issues are rarely viewed in that light, and are often treated as accounts payable (AP) exceptions that need fixing. Those might be duplicate invoices are flagged, price variances are investigated, and incorrect payment information is amended. The payment is eventually released, and the issue is considered closed.

But an operational fix doesn’t necessarily repair the damage created along the way, which might include strained business relationships and major errors that impact operations.

New findings from Amex Trendex research show how widespread these problems are. Ninety-percent of financial decision-makers surveyed reported that they have experienced payment errors in the last 12 months. Duplicate invoices, price variances, and incorrect payment information were among the most common payment errors.

For finance teams, those mistakes create added work. For the payer or vendor on the other side of the transaction, they can also raise questions about reliability, responsiveness, and trust.

That’s why payment accuracy is not solely an AP performance issue. It is an important part of the vendor-payer relationship.

 

Every Payment Sends a Message

Vendors are expected to deliver products and services accurately and on time. In return, they expect payers to process invoices and make payments according to the terms of their agreements.

When that process works consistently and as it should, it reinforces confidence between the parties. But the trust between payer and vendor can deteriorate through small frustrations repeated over time, whether that be an invoice that has to be resubmitted, a payment that arrives late without explanation, or an email asking for an update.

Amex Trendex research supports this, finding that 65% of financial decision-makers said inefficiency in their invoice and payment experiences make it more challenging to maintain strong buyer-supplier relationships. A late or inaccurate payment may suggest to a vendor that the customer lacks the processes needed to manage the relationship effectively. Repeated invoice errors from a vendor may prompt similar doubts from the payer. In either case, what begins as a transaction problem can become a trust problem.

This becomes more damaging when vendor relationships require cooperation beyond the original contract, as they often do. Payers may need expedited delivery, flexible order volumes, or help responding to unexpected disruptions. Vendors may need quick answers, clearer remittance information, or greater visibility on when payments will arrive. These additional needs, when layered on top of a broken process, create trouble spots.

 

Manual Work Creates Friction on Both Sides

Per this set of Amex Trendex findings, 82% of financial decision-makers surveyed say manual invoice processes increase the risk of costly human errors.

Manual processing can require invoice data to be entered into multiple systems, documents to be matched separately, and approvals sought through email. Each handoff introduces another opportunity for information to be missed, duplicated or entered incorrectly.

But here’s the decisive factor: the resulting work is rarely confined to AP. Procurement may need to confirm pricing, operations may need to verify delivery, and treasury may need to adjust a payment. That creates internal strife on top of the already existing strain between payer and vendor.

The Amex Trendex research found that 61% of financial decision-makers agree that employees spend too much time resolving such invoice- or payment-related issues. Collectively, respondents reported spending an average of 37 days each year processing and correcting invoices.

That is valuable time lost on both sides of the commercial relationship. Instead of discussing service improvements, future demand, or new opportunities, employees are doing detective work that should not have to happen in the first place.

Nearly one-quarter of financial decision-makers (23%) said improving the accuracy of invoice-based payment processing would have the biggest positive impact on their business, according to the Amex Trendex.

 

Long Processing Cycles Create Uncertainty

Buyers surveyed in the Amex Trendex reported spending an average of 32 business days processing an invoice payment, while suppliers reported an average of 29 business days.

Few business leaders would intentionally design a six-week process for something as fundamental as paying a vendor. Yet for many companies, that is effectively what has happened through years of disconnected systems, manual workarounds, and incremental process changes.

That three-day difference reflects how each side experiences the process. A payer may consider the work complete when an invoice is approved and submitted for payment. A vendor will not consider the transaction complete until the funds arrive and can be matched against the correct invoice, a process that is difficult and time-consuming to perform manually.

Whatever the reason may be for a given organization, a processing cycle of approximately six business weeks can leave vendors uncertain about their cash position and payers sending repeated requests for updates. Neither is an ideal outcome.

Visibility is crucial in these situations. When vendors can’t determine whether an invoice has been received, approved, or scheduled for payment, they often have little choice but to contact the payer, creating additional work on both sides.

Over time, that repeated friction can shape how both parties view the relationship. If it becomes a recurring routine, payers start looking for more reliable vendors that have modernized payment processing, and vendors come to see these payers as headaches.

 

When Relationship Problems Become Business Problems

The consequences of payment inefficiency extend beyond temporary frustration.

More than a third (37%) of financial decision-makers surveyed by the Amex Trendex reported that invoice-based payment challenges lead to higher expenses or missed cost savings. Delays and errors can contribute to additional processing costs, missed early payment discounts, and resources devoted to resolving preventable disputes.

The Amex Trendex also found that 67% of financial decision-makers believe agree payment inefficiencies make it more difficult for their businesses to operate at full potential. That result alone makes invoice and payment modernization more than a cost-reduction initiative. Improving the process can support stronger collaboration with external partners businesses rely on to serve customers, manage supply chains, and execute their strategies, making it an absolute must in 2026 and beyond.

 

A Better Payment Experience Supports Partnership

Payers and vendors agree on the importance of improvement. Ninety-two percent of buyers and 91% of suppliers surveyed said improving the payment experience for the other is increasingly important to their business relationships, according to the Amex Trendex.

Finance teams can respond by reducing manual data entry, standardizing invoice requirements, and connecting invoice, approval, and payment information more effectively. Automating processes shortens cycle times, improves error rates, and helps cut risk. Greater visibility also allows both parties to understand the status of an invoice without relying on email chains or repeated phone calls.

When payments are processed through secure, efficient channels like B2B payments networks, much of this friction disappears. If vendors can automate the delivery of invoices and payers can automate the approval and execution of payments, time savings and decreased frustration are inevitable. That’s why adoption is so crucial.

You can really feel the frustration with the lack of automation in many finance processes in the way financial decision-makers described the upside of fixing payments. For 35% of financial decision-makers surveyed in the Amex Trendex, never having to worry about payment or invoicing delays and errors again would feel like waking up and realizing it’s actually Saturday. One-third (33%) agreed that it would be like receiving a full year of three-day weekends.

These comparisons may be lighthearted, but the underlying message is serious business. Payment problems create stress because they affect employees and their responsibilities as well as business outcomes, not just records inside an accounting system.

When payments are accurate, visible, and predictable, it sends the message that both parties understand the value of the work and the importance of cash flow.  Vendors that gain confidence they will receive payments when they expect to, and with minimal detective work and follow-up are happy vendors. Payers who spend less time revisiting errors and past issues and more time focused on what’s next are happy payers.

In B2B payments, that kind of reliability is the lifeblood of every relationship. It’s one of the clearest ways businesses can show that they count on one another, and one of the most vital areas of improvement for a huge number of organizations.

Methodology

American Express commissioned a 7-minute online survey among n=521 U.S. Business Owners and/or Financial Decision-Makers (DMs) who manage or oversee specific business functions (including invoice-based payments; accounts payable/receivable; accounts reconciliation; business spend; cash flow; and working capital). The survey included n=100 buyers, n=164 suppliers and n=257 respondents who are both buyers and suppliers. Respondents’ organizations were either small (<100 employees, n=134), mid-sized (100-999 employees, n=200) or large (1,000+ employees, n=187). The survey was fielded between June 10-17, 2026.

At the total sample, the margin of error is +/-4 percentage points (ppts) at the 95% confidence interval. By role, the margins of error for the following are: Buyers, +/- 10 ppts; Suppliers, +/- 8 ppts; Both a Buyer and Supplier, +/-6 ppts.