Refunds and cancellations

A finalized invoice cannot be edited. Corrections are made with credit notes, which are negative documents linked to the invoice.

Which one to use

Situation	Use
The whole invoice is void	Cancel the invoice
Part of the invoice is refunded or adjusted	Create a credit note
The invoice is still a `draft`	Nothing to cancel: the draft has no number and no effect on balances. Create a new one if needed.

Apply the same rules to the sales invoice and to the matching purchase invoice lines of an order, so both sides stay consistent.

Cancel an invoice

curl https://api.nocotax.app/invoices/inv_123/cancel \
  -X POST \
  -u ${ACCOUNT_ID}:${YOUR_API_KEY}

Only a finalized invoice can be cancelled. Nocotax sets its status to cancelled and creates a credit note with the same items. order_reference and period are copied from the invoice and its lines to the credit note.

Partial correction

Create a credit note that references the invoice, and repeat the order_reference and period of the line you correct:

curl https://api.nocotax.app/credit_notes \
  -X POST \
  -u ${ACCOUNT_ID}:${YOUR_API_KEY} \
  -H "Content-Type: application/json" \
  -d '{
    "flow": "sales",
    "customer_id": "org_customer_123",
    "currency": "EUR",
    "invoice_id": "inv_123",
    "items": [
      {
        "title": "Partial refund - order ORD-12345",
        "order_reference": "ORD-12345",
        "period": { "start": "2025-12-15T00:00:00Z", "end": "2025-12-15T00:00:00Z" },
        "extratax_amount": 2500,
        "product": { "tax_code": "S10000000" }
      }
    ]
  }'

# Then finalize it
curl https://api.nocotax.app/credit_notes/cn_123/finalize \
  -X POST \
  -u ${ACCOUNT_ID}:${YOUR_API_KEY}

For a purchase invoice, use "flow": "purchases" and supplier_id. Amounts are positive: the document type gives the sign, and exports show credit notes as negative.

Why the references matter

The credit note has its own invoice date (the day you finalize it). If it only carried that date, a December correction finalized in January would be attributed to January.
order_reference ties the correction to the original order, so margin per order is net of refunds.
period tells which service period the correction relates to. See Accounting periods.

Refunding the money

Once a credit note is finalized, attach the money movement to it:

curl https://api.nocotax.app/credit_notes/cn_123/attach_credit \
  -X POST \
  -u ${ACCOUNT_ID}:${YOUR_API_KEY} \
  -H "Content-Type: application/json" \
  -d '{
    "transaction_data": {
      "amount": 2500,
      "currency": "EUR",
      "transaction_type": "refund",
      "reference": "re_abc123"
    }
  }'

transaction_type is refund, transfer_reversal or balance_adjustment. Without transaction_data, the full remaining amount is credited.

Getting started

Billing and invoicing

Implementation guides

Which one to use

Cancel an invoice

Partial correction

Why the references matter

Refunding the money

​Which one to use

​Cancel an invoice

​Partial correction

​Why the references matter

​Refunding the money

Which one to use

Cancel an invoice

Partial correction

Why the references matter

Refunding the money