Invoice verification

Invoice verification is the line-level check that every outgoing and incoming invoice matches the underlying contract, the delivered performance, and the applicable tariffs, indexations, and periods. Unlike total-based checks, line-level invoice verification also detects the structural errors that stay invisible in invoice totals: duplicate lines, underbilling, unbilled additional work, incorrectly applied indexation, or tariffs that deviate from the contractually prescribed values at that date. Effective invoice verification links every invoice line to the authorising contract clause and the corresponding execution data, and verifies the result through a four-eyes principle. See also: Solution — Invoice control.