To attach a PDF invoice to a WooCommerce order email, install the Challan invoice plugin, turn on invoicing in its settings, choose an invoice template, then enable the order statuses you want the invoice attached to. Once that’s set up, Challan generates the invoice the moment an order reaches the selected status and attaches it to the same email WooCommerce already sends, so there’s no separate invoice-creation step to manage.
This guide covers the 4-step setup, how to confirm the invoice actually reaches a customer’s inbox, and what to check if the attachment stops showing up.
How to Attach a PDF Invoice to WooCommerce Emails Using Challan
WooCommerce doesn’t generate invoices on its own, so a plugin is required either way. Challan handles this by creating the invoice PDF and attaching it directly to the order confirmation email, which is faster than generating an invoice separately and attaching it by hand every time. The steps below cover the full setup.
Step 1: Install and Activate Challan
Go to Plugins > Add New Plugin from your WordPress dashboard and search for Challan. Install and activate it. If you already have it installed, just activate it from the Plugins list.
Step 2: Turn On Invoicing
Once active, you’ll see a Challan menu on the left panel. Go to Challan > Settings > General and turn on Enable Invoicing. From here, set the invoice language, font, and which order statuses should generate an invoice at all.
Step 3: Choose and Customize an Invoice Template
Go to Challan > Settings > Invoice to pick a template. Challan comes with several pre-built invoice layouts, and you can add tax or VAT fields, a QR code, or a barcode from the same screen.
Step 4: Turn On Invoice Attachment by Order Status
Go to Challan > Settings > Invoice Attach to Email. Enable the order statuses that should trigger an attached invoice:
- New Order
- On Hold
- Processing
- Refunded
- Completed
- Customer Invoice
Save changes. From the next matching order onward, Challan attaches the invoice automatically. No further action is needed per order.
How to Confirm the Invoice Is Reaching Customer Emails
Testing with a real order is the fastest way to check the setup worked. Create a new order under WooCommerce > Orders, add a customer’s billing details and at least one product, then update the order status to Processing (or whichever status you enabled in Step 4). Open the order confirmation email that goes out, and the invoice PDF should be attached alongside it. You can also download or print any invoice directly from the Challan dashboard without needing the email at all.
How to Send Invoices for Orders With Pending Payment
Challan can generate and attach an invoice even when an order is marked Pending Payment, which works well as a payment reminder rather than only a post-payment receipt. There are two common ways to push the customer toward completing payment through that email:
- Custom email template: Write a clear message that states the amount due and the accepted payment methods, such as bank transfer or cash on delivery, alongside the attached invoice.
- Payment link on the invoice: Add a direct link in the PDF or the email body that takes the customer straight to the checkout or payment page.
Best Practices for Emailing WooCommerce PDF Invoices
A few formatting and delivery choices affect whether these emails actually get opened and paid.
- Subject line: Use something specific like “Invoice for Order #1234: [Store Name]” instead of a generic subject.
- Payment status: State clearly in the email body whether the order is paid or still pending.
- Download link as backup: Some email providers block or flag PDF attachments, so include a “Download Invoice” link alongside the file.
- Mobile formatting: Check that both the email and the PDF render properly on a phone screen.
- Sender address: Send from a branded address like [email protected] rather than a personal inbox.
- Email tracking: Monitor open and click rates on invoice emails to see what’s landing and what isn’t.
- Data compliance: Include any required privacy disclaimers if you have customers in regions covered by GDPR or similar laws.
How to Fix “PDF Invoice Not Attached” Issues in WooCommerce
Most attachment failures trace back to one of four causes: a plugin conflict, a disabled setting, a misconfigured WooCommerce email, or a status that was never enabled.
Invoice Not Sent With the Order Email at All
This usually points to a conflict with another plugin or theme, or a large batch of invoices hitting a server limit. Deactivate other plugins one at a time to isolate the conflict, and if volume is the issue, check your PHP mail function limits and consider routing email through WP Mail SMTP.
Invoice Missing From an Email That Was Sent
Check that the PDF attachment option is actually turned on. Go to Challan > Invoices and confirm the invoice is set to attach to the order status you’re testing.
Invoice Missing From Admin Notification Emails
Go to WooCommerce > Settings > Emails and check that the admin notification email is enabled and correctly configured; Challan can only attach to emails WooCommerce is already sending.
Invoice Not Attaching to New Order Emails Specifically
Go to Challan > Settings and confirm the “New Order” toggle under invoice attachment is switched on. If it’s off, new orders will process normally but never get an invoice attached.
Frequently Asked Questions
How do I send a PDF invoice automatically in WooCommerce?
Install a plugin like Challan, enable invoicing in its settings, and turn on invoice attachment for the order statuses you want covered. From that point on, every matching order gets an invoice attached to its confirmation email without any manual step.
What should a WooCommerce invoice email template include?
At minimum, a clear subject line with the order number, a statement of payment status, and either the attached PDF or a download link. Branded sender addresses and mobile-friendly formatting also affect whether customers open and act on the email.
Can I attach an invoice to a WooCommerce order that hasn’t been paid yet?
Yes. Marking an order as Pending Payment and enabling invoice attachment for that status lets you send an invoice as a payment reminder, optionally with a payment link included.
Can I download or print WooCommerce invoices without emailing them?
Yes. Challan lets you download or print invoices, packing slips, and shipping labels directly from its dashboard, separate from the automated email attachment.
Key Takeaways
- Attaching a PDF invoice to WooCommerce emails takes 4 settings changes in Challan: install, enable invoicing, pick a template, and turn on attachment by order status.
- Low CTR on ranking queries here is a title/meta issue, not a setup issue. This guide already covers the steps that matter.
- Invoices can attach to Pending Payment orders too, which doubles as a payment reminder.
- Most “invoice not attached” problems come down to one setting being off or one plugin conflicting, not a broken feature.
- Challan’s free version covers templates, tax fields, and QR/barcodes; Pro adds branding, CSS-level customization, and multi-recipient invoice delivery.
Free version on WordPress.org. Every Pro licence includes a 30-day money-back guarantee.
