Executive Summary
- Who: A major U.S. airline, 3.5 million invoices audited against $35B+ in spend over 18 months.
- The Problem: Overpayments piling up across suppliers, with airport authorities, one of the largest cost categories, typically excluded from audits as too complex to touch.
- The Fix: apexanalytix ran a full disbursement and supplier statement review and kept airport authorities in scope, applying the same claims process used for every other vendor.
- The Payoff: Nearly $20 million recovered across 1,500+ claims, a rate four times the industry average, led by one airport authority returning over $9 million.
Overview
A major U.S. airline engaged apexanalytix to conduct a comprehensive AP recovery audit covering its global accounts payable operations. The disbursement review spanned an 18-month period, analyzing 3.5 million invoices against $35B+ in auditable expenditures processed through SAP. A concurrent supplier statement review covered aged credits across thousands of supplier accounts.
At this scale, even a small error rate across millions of transactions adds up quickly. Credits go unapplied. Billing adjustments sit unresolved. Supplier accounts accumulate balances that no internal process is specifically tasked with recovering. This engagement was designed to find all of it, including the categories most airlines choose not to look at.
Challenge
For airlines, accounts payable is one of the most complex environments in any industry. Disbursements flow across thousands of suppliers in dozens of categories, from fuel and fleet maintenance to catering, technology, and facilities. The sheer volume and variety of transactions creates significant exposure to overpayments, unapplied credits, and billing errors that standard AP controls are not designed to catch.
Airport authority suppliers present a particular challenge. These are high-volume, multi-faceted relationships covering fees across gates, ground services, terminals, security, telecom infrastructure, and more. Contracts are long-standing, billing structures are complex, and the relationships themselves are often managed outside of AP by operations, facilities, or commercial real estate (CRE) teams. As a result, many airlines exclude airport authorities from recovery audit scope entirely, treating them as too sensitive or too difficult to engage through a standard supplier statement process.
That exclusion is costly. Without a dedicated process to identify and recover open credits, those balances accumulate quietly across fee categories, contract cycles, and years of billing activity, with no clear owner on either side working to resolve them.
Solution
apexanalytix conducted a full disbursement review and supplier statement program across the airline’s global operations, covering an 18-month period.
- Disbursement Review: Analyzed 3.5 million invoices against $35B+ in auditable spend, identifying duplicate payments, overpayments, unapplied credits, and billing discrepancies across six root cause categories.
- Supplier Statement Review: Engaged thousands of suppliers to obtain account statements and identify open credits not yet refunded or applied to future invoices.
- Airport Authority Inclusion: apexanalytix recommended keeping airport authority suppliers in scope, counter to the common industry practice of excluding them. The team applied the same structured outreach and claims process used for all other suppliers and pursued credits with the same depth of analysis.
- Structured Claims Process: All findings were documented, validated with suppliers, and tracked through to resolution, with regular reporting back to the client throughout the engagement.
Results
The audit produced nearly $20 million in finalized statement recoveries across 1,500+ claims.
Recovery rates across the airline and transportation sector average around 0.035% of auditable spend. This airline delivered more than four times that rate, the highest result among its peers.
The top supplier accounting for the largest amount of recoveries in the engagement was an airport authority, responsible for more than $9 million across 100+ credits. Several of those credits spanned 2019 through 2024 and covered reconciliation adjustments across Freedom Agreement fees, Liberty fees, gate boarding and security fees, telecom charges, CHRP true-ups, and ground rent settlements.
None of it would have surfaced under a standard scoping approach. By recommending airport authorities stay in scope and applying dedicated analysis to their complex, multi-fee billing structures, apexanalytix recovered credits that had been accumulating quietly for years with no clear owner on either side working to resolve them.
Conclusion
Airport authorities represent one of the most consistently overlooked recovery opportunities in airline AP. The relationships are complex, the fee structures span multiple internal teams, and the perceived sensitivity around these suppliers has led most carriers to exclude them from audit scope altogether. The result is that credits quietly accumulate, often going back years, with no one on either side working to resolve them.
apexanalytix brought a different perspective: scope decisions should follow the data. apexanalytix is built on the principle that supplier relationships should be respected, not strained. Effective, efficient communication that makes the recovery process easy for suppliers to engage with is what turns dormant credits into resolved claims. That approach produced the largest recovery area in the engagement and a recovery rate more than four times the industry average.
Top 6 Root Causes for Overpayment Recoveries
1. Reconciliation/Debit
Example: Credits left on inactive supplier accounts after a contract ends or a vendor is transitioned.
Recommendation: Require a credit sweep before deactivating any supplier account.
2. Return
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. Overpayment
Example: The company paid more than the correct amount due, often because of tax errors, billing mistakes, incorrect supplier selection, or system issues.
Recommendation: Implement stronger invoice validation checks across tax, supplier selection, and billing accuracy. Require exception review for high-risk or unusual invoice amounts.
4. Cancelled Invoice/Contract/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.
5. 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.
6. Other Duplicate Payments
Example: Duplicate payments identified through the Supplier Statement Review process that are either undetectable in the data or fall outside of the range reviewed in the Disbursement Review.
Recommendation: Establish a regular supplier statement review process to capture duplicate payments that fall outside standard disbursement data or detection ranges.
