How to Enter Vendor Invoice

Last reviewed: June 9, 2026

On this page

Use this workflow to enter a supplier invoice so PAX can track AP, vendor payment status, and PO accrual clearing correctly.

When to use this workflow

Use New Invoice when a vendor invoice has been received and needs to be recorded in PAX.

Use a PO-linked invoice when the invoice relates to a purchase order. Use a non-PO invoice when the payable should be charged directly to selected GL accounts without a purchase order.

Do not enter a vendor invoice before receiving the PO when the invoice is for purchased goods. PAX blocks unreceived PO invoices so receiving, accrued payables, AP, and costing stay in sequence.

Before you start

Confirm:

The vendor exists in PAX.
The vendor invoice number is known.
The invoice date is known.
The due date or vendor payment terms are known.
The invoice currency and exchange rate are correct when the vendor invoice is not USD.
The PO has been received if this is a PO-linked invoice.
The invoice line quantities and prices are ready to review.
Freight and tariff amounts are known when applicable.
GL accounts are known for non-PO invoices and any manually added lines.

Screen paths

Dashboard > Finance > Payables > Vendor Invoices > New Invoice
Dashboard > Purchasing > Vendor Invoices > New Invoice

Steps

Open Vendor Invoices.
Select New Invoice.
In Create Vendor Invoice, select the vendor from Vendor. Search by vendor code or vendor name, then choose the exact vendor option.
Enter Invoice Number.
Enter Invoice Date.
Review Due Date. PAX may calculate it from vendor payment terms after the vendor and invoice date are selected. You can change the due date if needed.
If the invoice relates to a PO, select it in Link to Purchase Order (Optional).
Review Vendor Invoice Currency and Rate: 1 USD =.
Review the line items.
For each line, confirm the description, GL account, vendor quantity, vendor price, stock quantity preview, vendor amount, and USD amount.
Add a line with Add Line Item when a non-PO invoice needs a manual line, or when a PO invoice needs an additional manually coded line.
Enter Freight Amount and Tariff Amount when applicable.
Select the correct Status.
Add Notes when helpful.
Review Vendor Subtotal, Freight + Tariff, Vendor Total, and USD totals.
Select Create Invoice.
Return to the invoice list and confirm the invoice appears with the expected vendor, PO, total, due date, and status.

PO-linked invoices

When a PO is selected, PAX loads PO lines and shows received quantity available to invoice.

For PO lines, use the Received / Available column to avoid over-invoicing. The available quantity is based on PO quantity received minus quantity already invoiced on non-deleted vendor invoices.

If PAX shows an accrued payables warning, review it before continuing. The warning means the invoice amount is less than the available received value, so an amount will remain in accrued payables after the invoice is saved.

If the PO has no received quantity, PAX blocks invoice creation. Receive the PO first from Receiving Overview.

Non-PO invoices

For invoices without a PO, manually add invoice lines and select the correct GL account on each line.

Use this path only when the payable truly does not belong to a purchase order workflow. If a PO exists, linking the invoice to the PO gives PAX the information it needs for PO accrual review and AP clearing.

What happens behind the scenes

When Create Invoice is selected, PAX:

Validates required invoice header fields.
Validates that at least one line item has quantity greater than zero.
Requires description and unit price on invoice lines.
Requires GL accounts for non-PO invoice lines and manual lines.
Converts vendor quantities and vendor prices into stock quantities and USD amounts using the invoice exchange rate and unit conversion factor.
Stores invoice header values and invoice line values.
Prevents PO-linked invoice quantities from exceeding received quantity available to invoice.
Calls the accrual-to-AP posting routine for PO-linked invoices.
Runs invoice price adjustment processing for invoice-to-PO variances.

If the invoice is PO-linked and PO payment activity already exists, PAX may set the saved invoice status according to paid amount against the PO.

Troubleshooting

The PO cannot be selected

Likely cause: A vendor has not been selected, or the PO does not belong to the selected vendor.

Safe fix: Select the vendor first, then choose from the PO list for that vendor.

Contact support if: The PO belongs to the vendor but does not appear.

PAX blocks the invoice because the PO is unreceived

Likely cause: Goods have not been received against the PO in PAX.

Safe fix: Receive the PO first, then return to Vendor Invoices.

Contact support if: Receiving is complete but PAX still blocks the invoice.

A GL account is required

Likely cause: The invoice line is not coming from a PO line, or it was manually added.

Safe fix: Select the correct GL account before saving. Do not choose a temporary account just to pass validation.

Contact support if: The correct account is missing from the list.

The invoice quantity is rejected

Likely cause: The quantity exceeds the PO quantity received and available to invoice.

Safe fix: Review existing vendor invoices and PO receiving before changing the quantity.

Contact support if: Available quantity does not match the actual PO receiving and invoice history.