Customize Xero invoices with code

Use these examples to change how WooCommerce Xero builds invoices and handles refunds. Add custom PHP through a small site-specific plugin or a code-snippet manager, test it on a staging site with a separate Xero app, and keep a way to disable the code if an error prevents access to WordPress.

Use the current date for invoices and due dates

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WooCommerce Xero normally uses the order date for the invoice date and uses the connected Xero organization’s payment terms to calculate the due date. This example replaces both values with the date on which the invoice is sent. Priority 20 ensures the due-date callback runs after the extension’s payment-terms callback.

/**
 * Use today's date for Xero invoice and due dates.
 *
 * @return string
 */
function your_prefix_xero_use_current_date() {
	return wp_date( 'Y-m-d' );
}

add_filter( 'woocommerce_xero_invoice_date', 'your_prefix_xero_use_current_date', 20, 0 );
add_filter( 'woocommerce_xero_invoice_due_date', 'your_prefix_xero_use_current_date', 20, 0 );

Disable automatic voiding after a full refund

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By default, the extension attempts to void the associated Xero invoice when an order becomes fully refunded. Use this filter when another accounting workflow will handle the invoice. Paid invoices still need to be adjusted in Xero.

add_filter( 'woocommerce_xero_disable_auto_void_invoices', '__return_true' );

Send invoices to Xero as drafts

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The extension sends invoices with an AUTHORISED status. This example changes only the invoice status element to DRAFT.

/**
 * Send WooCommerce Xero invoices as drafts.
 *
 * @param string $xml Invoice XML.
 * @return string
 */
function your_prefix_xero_use_draft_status( $xml ) {
	return str_replace(
		'<Status>AUTHORISED</Status>',
		'<Status>DRAFT</Status>',
		$xml
	);
}

add_filter( 'woocommerce_xero_invoice_to_xml', 'your_prefix_xero_use_draft_status' );

Let Xero generate the invoice number

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Returning null from the invoice-number filter omits InvoiceNumber from the request, allowing Xero to assign the next number in its sequence. Test this with your invoice prefix and reconciliation process before using it on live orders.

add_filter( 'woocommerce_xero_invoice_invoice_number', '__return_null' );

Understand account-code customization limits

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The woocommerce_xero_line_item_account_code filter can replace an account code, and its line-item object exposes the associated order. It does not expose the original WooCommerce order item or product. A reliable product- or category-based mapping therefore needs additional custom code that preserves that relationship earlier in the invoice-building process. Do not infer a product from the line description because names are not guaranteed to be unique.

Filter reference

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• woocommerce_xero_invoice_date — Filters the invoice date string. Also receives the WC_XR_Invoice object.
• woocommerce_xero_invoice_due_date — Filters the due date string. Also receives the WC_XR_Invoice object.
• woocommerce_xero_invoice_invoice_number — Filters the invoice number. Return null to omit it. Also receives the WC_XR_Invoice object.
• woocommerce_xero_invoice_to_xml — Filters the complete invoice XML string. Also receives the WC_XR_Invoice object.
• woocommerce_xero_invoice_request_settings — Filters the WC_XR_Settings object used for the request. Also receives the WC_XR_Invoice object.
• woocommerce_xero_disable_auto_void_invoices — Filters whether the extension attempts to void an invoice after a full refund.
• woocommerce_xero_line_item_account_code — Filters the account-code string. Also receives the WC_XR_Line_Item object.
• woocommerce_xero_line_item_description — Filters the description string. Also receives the WC_XR_Line_Item object.
• woocommerce_xero_create_unique_tax_label — Filters whether the tax percentage is appended to make a tax label unique.
• woocommerce_xero_payment_invoice_id — Filters the Xero invoice ID associated with a payment. Also receives the WC_XR_Payment object.
• woocommerce_xero_payment_date — Filters the payment date string. Also receives the WC_XR_Payment object.