Supplier refund, debit note, credit note

Purpose

Use these three adjustment documents when a plain purchase invoice, cash purchase, or payment is the wrong tool.
Advance paid before a bill is Deposit to supplier, not these three.
Screen: Purchase → Purchase Document, then Refund, Debit Note, or Credit Note.
Maintain Knock-Off applies credit notes and payments to invoices.
Credit note in chat: Purchases & money out → Purchase credit note, or Record a purchase credit note. Confirm before posting. You can knock off invoices in the same flow.
Refund and debit note have no live wizard. Ask “how to…” and use the screen.
Do not type “how to record a purchase credit note” if you want the wizard. Use Record a purchase credit note.

The supplier exists.
For refund: a bank or cash account for Payment By on the chart of accounts — the account the supplier pays into.
For a credit note or debit note linked to a self-billed e-Invoice: the original invoice should already be validated if you are adjusting a MyInvois document.
Know whether you still owe them or have already paid.

Return or overcharge, and you still owe less. Use Credit Note.
Extra charge after the invoice (you owe more). Use Debit Note.
You already paid, and they return money. Use Refund. A credit note alone is for when you still owe less, unless you first reduce the bill and then refund.
Paid at the counter with the buy. Use Cash Purchase.
Pay an existing invoice. Use Payment.
Advance before they invoice. Use Deposit to supplier. Payment waits until there are invoices to knock off.

You cannot edit the invoice on MyInvois. Cancel within 72 hours, or issue a credit note, debit note, or refund note.
You may issue both a credit note and a refund note on one original e-invoice. Credit note first (reduces the amount still payable). After you have paid, refund note for the net amount paid.
If the credit note cancelled the invoice, do not also issue a refund note.

Purchase → Purchase Document → Debit Note → New Supplier Debit Note.
Same header and lines idea as a purchase invoice: supplier, date, lines, account, tax.
Click Save. Supplier outstanding increases.
Pay with Payment. Submit E Invoice if you self-bill.

Purchase → Purchase Document → Credit Note → New (file-plus).
Select Supplier. Enter lines (what they credit: return, discount, or overcharge).
Under Knock-Off Invoices/Debit Notes, tick the original bills, or type a partial pay. Same rules as a payment. UnApplied cannot be below zero.
Click Save. Supplier outstanding decreases. Stock (Premium) goes out if you return items.
Submit E Invoice when required.
Assistant: Record a purchase credit note → supplier, lines, then knock-off (oldest first, or choose) → confirm.

Purchase → Purchase Document → Refund → New Refund.
Supplier (required), bank or cash (Payment By — the account the refund is received into), Paid Amount, Date.
Knock off the invoices, debit notes, or payments this refund relates to.
Click Save.
Submit as an e-Invoice refund note when the original was a validated self-billed e-invoice.

Aging still high after a return. You needed a Credit Note and knock-off, not only a remark on the invoice.
Paid supplier wants to send money back. Use Refund. If the invoice is already fully paid, follow the e-Invoice rule above: credit note, then refund note, and skip the refund note if the credit note cancelled the invoice.
Cannot edit a validated e-invoice. Cancel within 72 hours, or issue a credit note, debit note, or refund note.
Unapplied below zero on a credit note. You credited more than the bills you ticked. Reduce the knockout pay, or add bills.
Stock did not come back on a return. Put item codes on the credit note (Premium).