# Duplicate invoice checks in Dynamics 365 Finance for builders

Dynamics 365 Finance has duplicate invoice checks built in. Subcontractors resend claims when payment is slow. A resent claim with a new invoice number looks like a new bill and can be paid twice.

## Why it matters for builders

- Progress claims are numbered and often look the same except for the claim number and amount. Duplicates hide in the small differences.
- Plant hire and bin companies bill weekly with similar amounts, so a repeat charge is easy to miss.

## For builders in Dynamics 365 Finance

- Set Check the invoice number used on Accounts payable parameters to Reject duplicate. Finance then rejects an invoice number that is already posted for the same vendor.
- A Feature management option can stop an invoice with a repeated number from being submitted to workflow. The submitter sees the alert.
- Claims need a fresh invoice number each time. If a subcontractor reuses the number for claim 2, the check treats it as a repeat of claim 1. Ask for a unique number for each claim.
- The check looks at the number only. A claim re-keyed under a different number is not caught.
- Fill in the Invoice date on every claim. It is blank by default, and the Invoice received date and Posting date default to today. Having all three dates on the record helps you tell a resent claim from a new one.
- If the check raises an alert on a submitted invoice, the submitter can correct the number and resubmit it.

## What Dynamics 365 Finance does on its own

The Check the invoice number used setting on Accounts payable parameters can reject an invoice number that already exists on a posted invoice for the vendor.

The comparison is per vendor against posted invoices, including invoices that arrive through a web service.

What you need and the setup steps: https://www.pulsify.tech/duplicate-invoice-checks-for-dynamics-365-finance/

## Example

Example Formwork Pty Ltd emails claim 5 as INV-0506 for $22,000 ex GST. Two weeks later they email it again as INV-0507 with the same amount and the same job reference.

- Claim 5, formwork level 4: $22,000.00 (Same supplier, amount and job as an earlier bill)
- GST: $2,200.00 (Matches the earlier bill)
- Invoice number INV-0507 (Different from the first number, so a number-only check misses it)

The check flags a likely duplicate on supplier, amount and job. The second bill goes back to the subcontractor instead of the pay run.

## Common mistakes

- Checking only the invoice number, so a resent claim with a new number gets through.
- Paying a final claim without checking it against progress claims already paid.

## Step-by-step guides for Dynamics 365 Finance

- How to stop paying a vendor invoice twice in Dynamics 365 Finance: https://www.pulsify.tech/how-to/stop-paying-a-bill-twice-in-dynamics-365-finance/

## What Pulsify adds

Pulsify checks every invoice for a duplicate, including bills keyed straight into Dynamics 365 Finance, and asks before approval. Pulsify connects to Dynamics 365 Finance. We set up the connection for you. More: https://www.pulsify.tech/duplicate-invoice-checker/

## Common questions

### Will Finance reject a second progress claim with the same invoice number?

Yes, if Check the invoice number used is set to Reject duplicate. It compares the number for the same vendor against posted invoices. Ask the subcontractor to number each claim. A claim keyed under a new number would not be caught by this check.

### Should a final claim be checked against earlier claims?

Yes. A final claim should equal the order value plus approved variations, minus what you have already paid and retention you still hold. Check the running total before you approve.

### Does Finance reject duplicate invoice numbers?

Yes. Set Check the invoice number used to Reject duplicate. It compares the number against posted invoices for the vendor. A warning-only choice also exists.

## Sources

- https://learn.microsoft.com/en-us/dynamics365/finance/accounts-payable/vendor-invoices-overview
- https://learn.microsoft.com/en-us/dynamics365/finance/accounts-payable/vendor-invoice-dates
- https://learn.microsoft.com/en-us/dynamicsax-2012//accounts-payable-parameters-form
- https://www.nsw.gov.au/housing-and-construction/compliance-and-regulation/security-of-payment/responding-to-a-payment-claim

Source: https://www.pulsify.tech/duplicate-invoice-checks-in-dynamics-365-finance-for-builders/ (last checked 2026-10-19)