How to attach files to WooCommerce emails

First decide whether the customer truly needs an email attachment. If the file is a purchased digital product, edit the product and enable Downloadable, then add the file under Downloadable files. WooCommerce sends the customer a download link in the order email and can also show it under My account → Downloads. This is usually safer for large files and lets you control download limits and expiry.

Use an actual attachment for documents such as a fixed terms PDF, packing slip or product manual that must arrive with a particular email. WooCommerce does not offer a general core setting for attaching arbitrary files to every order email.

For one fixed file on one standard customer email, add a small PHP snippet with a snippets plugin or a child theme. WooCommerce passes the attachment list, email ID, order and email object through the woocommerce_email_attachments filter.

add_filter( 'woocommerce_email_attachments', 'my_woocommerce_email_attachments', 10, 4 ); function my_woocommerce_email_attachments( $attachments, $email_id, $order, $email ) { if ( 'customer_completed_order' === $email_id ) { $attachments[] = '/absolute/path/to/file.pdf'; } return $attachments; }

Replace the placeholder with the file's absolute server path, not its web URL. For a processing-order message, use the confirmed email ID for that message instead of copying the completed-order ID. The filter and four-argument pattern are commonly used for this task.

Do not attach the file without checking the email ID. Otherwise the same document may be added to admin notifications, customer messages and manual resend emails. Keep the condition inside the filter and target only the customer email that needs the document.

The standard WooCommerce email settings are under WooCommerce → Settings → Emails. Those settings control each email's recipients, subject, heading and content, but an attachment normally comes from an extension or custom code rather than the standard email editor.

If each product, category or order status needs a different PDF, the manual snippet becomes custom development. It must inspect the order's line items, find the related files, convert selected media references into server paths and avoid attaching duplicates when several products use the same document.

This is also where stores commonly break: a file URL is supplied where the mailer needs a local path, the code runs before a generated PDF exists, or a file is attached to every email instead of the intended status. For product attachments, use an extension that can assign files to products or categories and include them in order emails.

Place a low-value test order using the same product and payment method as a real customer. Trigger the exact status that should send the message, then confirm the attachment opens and has the expected filename, size and contents.

Also test an order that should not receive the file. If the email fails or arrives without its attachment, check that the path exists on the server, the web server can read the file, the email ID matches the message being sent and your mail service permits the attachment size. Large files are often better delivered as protected download links.

For a non-technical setup, install and activate WooCommerce Email Attachments, then configure the attachment rules from its settings. This is the quicker route when you need several file types, multiple attachments, product or category rules, order-status conditions or limits without maintaining PHP code.

WooCommerce extensions that handle attachments generally provide an email selector and an upload or media-library control. For example, the WooCommerce Email Attachments documentation describes selecting registered WooCommerce emails and assigning uploaded files to them.