Case Study

The Deal That Was Too Good to Be True, and Then Wasn’t

A $40 million e commerce retailer lost more than $350,000 over five years to a single line nobody thought to check. Multiple processors had reviewed the account and told them it was one of the best deals they had ever seen.

E Commerce and Online RetailInterchange ManagementReturn ProcessingProcessor Deception

$350K+

Cumulative overcharges over five years

$70K

Annual hidden overcharge

17.5

Basis points added to true cost

Years undetected

The client

A well run business that had done everything right

Our client was a mid size e commerce retailer processing approximately $40 million annually. Not a household name, no outsized brand leverage, no Fortune 500 bargaining power. Just a well run online business that had done everything right when it came to managing payment processing costs.

Or so everyone believed.

The challenge

Everyone said the deal was clean

The client had been diligent. Over the years they shopped the deal with multiple processors, and every time the answer came back the same: you have a great deal, one of the best we have seen. Low discount rate. No add on fees. Clean statements. Nothing to find.

When they heard weAudit Managing Partner Robert Day speak at a conference, they were intrigued enough to reach out, and skeptical enough that they almost did not move forward. Why would a forensic audit find anything that several processors and their own internal reviews had already cleared?

Industry reality check

When a processor reviews a merchant’s statement and says the deal looks great, that is not an audit. It is a sales call. The person reading the statement is usually a sales representative with less than two years in the industry, looking for one thing: can I beat this rate by enough to win the account?

They are not trained forensic auditors. They are not independent. And they have every incentive to miss what is not obvious, because if the deal looks clean they move on to the next prospect. This client had been through that process several times. It missed the problem every single time.

The investigation: fresh eyes find what others miss

weAudit’s forensic team started with no assumptions. At first they reached the same conclusion as everyone else. The deal looked exceptional. The discount rate was genuinely low. There were no junk fees. The statements appeared clean.

Rather than close the file, the team did something that separates a real forensic audit from a sales review. They set it aside. Auditors were moved onto other work, told to reset completely, and brought back to the account later with fresh eyes and nothing carried forward. Start again.

That discipline uncovered what five years and multiple reviews had missed. The processor was retaining the interchange fees on returned transactions. On the surface, easy to overlook. On any single statement, a rounding error. But this was an e commerce retailer with high return volume, and the math was devastating.

What was found

What was found	How it worked	The real cost
Interchange retained on returns	When a customer returns a purchase, the interchange fee paid on the original transaction should be credited back to the merchant. This processor was keeping it.	$70,000+ per year, invisible inside the broader statement because the discount rate itself was legitimately low.
True rate disguised by a low headline rate	The low discount rate created a credible decoy. Every reviewer focused on the rate and saw a clean deal. Nobody tracked the interchange credits on returns across the full statement volume.	17.5 basis points added to true effective cost, turning a great deal into a damaging one.
Five years of cumulative exposure	Because no audit methodology had ever caught it, the practice continued uninterrupted from the day the original contract was signed.	$350,000+ extracted from the merchant over the life of the relationship, before weAudit was engaged.

The outcome

The finding was presented to the client with full documentation. The response was what you would expect from a finance team that had just learned a trusted partner had been quietly taking $70,000 a year out of the bottom line for over five years.

This was not a billing error. It was a structural decision: offer a headline rate attractive enough to stop the merchant from shopping, and recover the margin through a mechanism obscure enough that no ordinary reviewer would find it.

The client switched processors entirely. weAudit managed the transition and confirmed the new agreement contained none of the same traps. The $70,000 annual overcharge stopped the month the switch took effect.

We had been told by everyone, including other processors, that we had one of the best deals they had ever seen. weAudit found what five years and every one of them had missed.

Merchant, $40M e commerce retailer

Why this case matters

A processor does not offer a genuinely exceptional rate out of generosity. When the headline numbers look too good, the right question is not “is this a great deal?” It is “where is the margin they are not showing me?”

For e commerce merchants, return volume is the silent variable most agreements exploit. Interchange credits on returns require cross referencing transaction level data, which is work a sales representative doing a rate review will never perform, and which most internal finance teams are not equipped to catch. If you want to see how these charges appear on a real statement, walk through our annotated merchant statement example.

When everyone else said there was nothing to find, weAudit found $350,000. This engagement also predates our current technology. Today our proprietary auditing system flags this exact category of overcharge automatically, at the transaction level, on the first pass, in minutes rather than through a full methodical reset.

Has anyone actually audited your statements?

A rate review from a processor is a sales call. An independent forensic audit is a different exercise entirely. See how our audit works, or read what it costs.

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Client identity withheld at the client’s request. All figures are drawn from the engagement record.