An invoice query is easier to explain when the disputed line is separated into quantity and rate. This checker compares the billed figures with the figures supported by your records and shows an arithmetic breakdown of the difference. Use it to prepare a focused question for the supplier rather than treating an unexplained difference as proof that the whole invoice is wrong.
Invoice line variance checker
Compare a billed line with the quantity and rate in your records.
Use matching units and prices excluding tax. The output identifies an arithmetic variance for investigation.
What the result shows
The checker calculates the billed line as billed quantity multiplied by billed rate and compares it with the supported quantity multiplied by the agreed rate. It then separates the difference into a quantity effect at the agreed rate and a rate effect on the billed quantity. Those two components reconcile to the overall difference, making the arithmetic easier to explain in a supplier query.
Prepare the information for this review
The labels in the tool describe the measurement or record needed for each input. The following checks help keep the entered information consistent with the case you intend to review.
- Invoice or line reference: Use a clear name, reference or description that can be matched to your records. Expand abbreviations where the person receiving the result may not know how your business uses them.
- Billed quantity: Enter a plain number in the unit shown, without a currency symbol or thousands separators. Keep the same measurement basis throughout the comparison and retain the source figure for checking.
- Quantity supported by your records: Enter a plain number in the unit shown, without a currency symbol or thousands separators. Keep the same measurement basis throughout the comparison and retain the source figure for checking.
- Billed rate (£ per unit): Enter a plain number in the unit shown, without a currency symbol or thousands separators. Keep the same measurement basis throughout the comparison and retain the source figure for checking.
- Agreed rate (£ per unit): Enter a plain number in the unit shown, without a currency symbol or thousands separators. Keep the same measurement basis throughout the comparison and retain the source figure for checking.
Check the result against the source records
Use matching units and prices excluding tax. The output identifies an arithmetic variance for investigation.
Start with one case whose inputs you can trace back to the original records. Run the tool and compare its labels, units and dates with that example before preparing a wider review. If a value is uncertain, record the uncertainty in your working notes and resolve it with the person who holds the source information. A neatly presented result is useful only when the assumptions behind it are also clear.
Keep a copy and agree the next action
Use Download report to keep the written result and Download results CSV when you want to work with its records in a spreadsheet. Save inputs keeps a JSON file that can be restored into this same tool later. Editing an input hides the old result until you run the tool again, which helps avoid sharing an output that belongs to an earlier set of assumptions.
Where report emailing has been configured, Email my results lets you request a copy and send the same inputs and result to this site for follow-up about your request. The form explains who receives the copy and requires a completed security check. Check the recipient address carefully before sending. The email request uses the current result, so review the entered information before choosing that option.
For help with the next step, Explore specialist support.