Overview
A global energy company with major upstream operations across North America has partnered with apexanalytix on AP recovery auditing since 2004. Over that time, the program has delivered more than $20 million in audit recoveries and continued to grow in scope and results with each engagement.
The most recent audit was the strongest the partnership has produced. Supplier response rates reached an all-time high, and one supplier returned more than $750,000, driving the largest single-year recovery in the program’s history.
Challenge
At this company’s scale, processing nearly 750,000 invoices in a single year leaves little room for manual detection of overpayments. With billions in disbursements flowing through SAP, errors do not surface on their own. They accumulate across vendor transitions, cancelled contracts, coding inconsistencies, and supplier-side mistakes that go unreported.
No internal review process catches all of it reliably, and suppliers do not always proactively flag credits owed to the customer. The challenge is not just identifying what went wrong. It is building a recovery program that suppliers engage with consistently, so that findings get resolved rather than disputed or delayed.
Solution
apexanalytix conducted a full disbursement review covering a full calendar year, analyzing approximately 750,000 invoices against more than $14 billion in auditable spend processed through SAP across North American operations. A supplier statement review ran concurrently, covering aged credits across thousands of supplier accounts.
- Disbursement Review: Analyzed the full population of invoices to identify duplicate payments, unapplied credits, and billing errors.
- Supplier Statement Review: Contacted thousands of suppliers to obtain account statements and identify credits that had not been applied or refunded.
- Supplier Engagement: Worked directly with suppliers to validate findings and resolve claims, achieving the highest supplier response rates in the program’s history.
- Trend Analysis: Tracked recovery reasons across audit cycles to identify patterns, prioritize high-value claim types, and surface process improvement opportunities for the client.
Results
The audit resulted in a multimillion-dollar recoveryacross hundreds of claims, the largest total the program has produced in its 20-year history.
Supplier engagement was the defining factor. When suppliers respond to findings, claims get resolved. This audit saw the highest response rates on record, and two suppliers in particular drove a significant share of the outcome.
One supplier alone accounted for more than $750,000 in recoveries, representing the largest single-supplier contribution in the program’s history. That total was driven by over 150 individual credits stemming from joint buybacks in 2024 that had not been applied back to the customer’s account.
A second supplier had a single credit of approximately $165,000 tied to a platform migration. During the transition to a new invoicing system, three invoices were voided and reissued on the supplier’s end after they had already been submitted to and paid by the customer. The overpayment sat unresolved until the audit identified it and the supplier engaged to confirm the facts.
Top 5 Root Causes for Overpayment Recoveries
1. Cancelled Invoice, Contract, or Service
Example: Unprocessed credits often occur when lines of business do not communicate cancellations or changes quickly, even though they typically know about these adjustments first.
Recommendation: Process or accrue expected credits as soon as they are identified and reduce blanket POs by adjusting available PO funds when changes occur.
2. Returns
Example: When goods returned to the supplier for which a credit was not properly communicated to Accounts Payable.
Recommendation: Strengthen communication between operations and AP so returns are shared immediately and require suppliers to issue credit memos promptly for all returned items.
3. Payment in Error
Example: When a payment is made to an incorrect supplier or payment of an incorrect invoice
Recommendation: Confirm supplier and invoice details before releasing any payment, and flag transactions that don’t match an approved PO or vendor record.
4. Inconsistent Invoice Coding
Example: Invoices are coded incorrectly or differently than expected, which can cause them to be routed, recorded, or paid incorrectly.
Recommendation: Be consistent through clearer processes, better personnel training, and stronger system checks.
5. Supplier Coding Error
Example: An invoice from a supplier was coded to the wrong vendor record due to similar supplier names in the vendor master file, resulting in payment being issued to the incorrect supplier.
Recommendation: Use clear supplier names and simple checks when entering invoices so payments go to the correct supplier.
Conclusion
Long-term audit partnerships compound in value. Over 20 years, the institutional knowledge, supplier relationships, and audit methodology built through this program have all strengthened together.
The 2024 audit reflects that. Record supplier response rates produced record recoveries, including two standout findings that together accounted for nearly $1 million recovered across hundreds of claims. It was the strongest year the program has seen, and with more than $20 million recovered since the partnership began, the results speak to what consistent, structured AP auditing produces over time.
