How to audit a Cintas invoice without guessing.

A useful invoice audit starts with objective reconciliation. Before deciding that a charge is wrong, identify the exact line, amount, date and type of change.

Step 1: preserve the original digital PDFs

Original PDFs usually contain selectable text and structured coordinates. They are easier to compare reliably than screenshots or phone photos.

Step 2: normalize recurring lines

Compare recurring items using stable identifiers where possible, such as material codes and normalized descriptions. Repeated employee-level rows may need to be grouped before totals are compared.

Step 3: separate price, quantity and fee changes

• Price change: same recurring item, different unit price.
• Quantity change: same recurring item, different billable quantity.
• Fee change: recurring service or surcharge amount changes.
• New item: charge appears only on the newer invoice.
• Removed item: charge appears only on the older invoice.

Step 4: verify the printed totals

Automated extraction should be checked against the printed invoice total. If the source PDF cannot be read confidently, the software should ask for review rather than inventing a value.

Step 5: only then review the contract

Invoice comparison can tell you what changed. It cannot by itself determine whether that change was allowed under a service agreement. Contract review is a separate step and may require amendments, notices and service-change records.