Resource
Vendor Overbilling
Vendor overbilling can come from rate drift, missed credits, duplicate payments, incorrect surcharges, statement mismatches, or contract terms that were not applied after renewal or expansion.
- Compare line items against contract terms, rate sheets, POs, approved change orders, and renewal language.
- Look for recurring fee changes, surcharges, minimums, and tier changes that were never approved or never reconciled.
- Track claim status separately from future savings opportunities so recovery totals stay credible.
Where overbilling usually appears
- A vendor keeps billing an old rate after a renegotiated agreement starts.
- A temporary surcharge becomes recurring but never appears in the contract or approval trail.
- A contract includes volume pricing, but invoices continue using the higher tier after volume thresholds are met.
- A credit memo exists, but the credit was applied to the wrong entity, location, or account.
Evidence needed before outreach
- The invoice line or statement balance at issue.
- The contract clause, rate sheet, PO, or credit memo that contradicts the charge.
- The payment record showing the customer paid or remains exposed to the disputed amount.
- A plain-language explanation of the requested refund, credit, offset, or correction.