ERP guides
Accounts payable in Microsoft Dynamics 365 Business Central
What Business Central checks for you, the reports that show what was paid, and where duplicates and overpayments slip through.
- Duplicate paymentsThe built-in duplicate check, its gaps, and how to find bills already paid twice.
- Duplicate vendorsWhy the same supplier ends up in the vendor list twice, and how merging works.
- Payment terms and discountsHow terms and discounts are held, and the mistakes that lead to overpaying.
Business Central's duplicate bill check
- Turning on Ext. Doc. No. Mandatory in Purchases & Payables Setup means a purchase invoice or credit memo cannot be posted without the vendor's invoice or credit memo number. Source 1 (opens in a new tab)
- Microsoft's documentation notes that Business Central doesn't check whether external document numbers are unique, so making the number required does not by itself catch a duplicate. Source 2 (opens in a new tab)
Checked against the vendor's documentation on Nov 6, 2026. Products change; the vendor's current help is the final word.
Reports for reviewing payables
- The Aged Accounts Payable report (322) shows open vendor balances by age. Source 1 (opens in a new tab)
- The Vendor - Detail Trial Balance report (304) lists each vendor's ledger entries for a period. Source 2 (opens in a new tab)
Checked against the vendor's documentation on Nov 6, 2026. Products change; the vendor's current help is the final word.
Merging duplicate vendors
- On the vendor card, Merge With opens the Merge Duplicate page, where the duplicate can be removed or renamed. It needs the MERGE DUPLICATES permission set and cannot be undone. Source 1 (opens in a new tab)
Checked against the vendor's documentation on Nov 6, 2026. Products change; the vendor's current help is the final word.
Payment terms and discounts
- Payment discounts are calculated from the payment terms when a document is posted, and the same payment terms are used for purchases. Source 1 (opens in a new tab)
Checked against the vendor's documentation on Nov 6, 2026. Products change; the vendor's current help is the final word.
In a paid-bills export from Business Central, the supplier's invoice number is in the External Document No. column. Export paid bills from Microsoft Dynamics 365 Business Central.