Automate duplicate bill checks in Xero
Duplicates slip in through forwards, resends and statements. Modern checks every new bill in Xero against recent bills from the same supplier and flags likely duplicates in Slack before anyone pays them.
TriggerWhen a bill is created in Xero
Steps4 steps, from trigger to sign-off
ControlAP lead approves before any bill is voided
Free to start. No card needed.
The instruction
“When a bill is created or edited in Xero, compare it with bills from the same supplier over the last 12 months. Flag it if the invoice number matches after removing spaces and prefixes, or if the amount matches within 1% inside 30 days. Post flagged bills to #ap in Slack with both bills linked, and void the duplicate only if the AP lead approves.”
Works with every major ERP






- +100 more
How it runs
4 steps from trigger to sign-off
- 01
Watch new bills
Picks up every bill as it is created or edited in Xero, including drafts.
Xero
- 02
Compare with history
Checks invoice numbers, amounts, dates and PDFs against 12 months of bills from the supplier.
Modern
- 03
Flag the match
Posts both bills side by side in #ap with the reason they look like duplicates.
Slack
- 04
Approve the fix
The AP lead confirms in Slack, then Modern voids the extra bill in Xero.
Xero
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FAQs
Flag duplicate bills before they are paid: FAQs
Can’t find what you’re looking for? Send us a message and a person on the team will answer.
By default, the same supplier with a matching invoice number, or the same amount within 30 days. You can tighten or loosen the rules in the instruction.
No. It flags likely duplicates and only voids a bill after the AP lead approves.
Yes. Modern runs the same checks on bills in QuickBooks, NetSuite, Sage or Xero.