How to Send an Invoice PDF

The most common ways to deliver an invoice to your client.

Updated March 9, 2026 by invoice.Now.

Why PDF?

PDF is the standard format for invoices because it preserves your layout across every device and operating system. It cannot be accidentally edited by the recipient, it prints cleanly, and it is easy to archive. Most clients and accounting departments expect invoices as PDF attachments.

Method 1: Email Attachment

The most common approach. Create your invoice, export it as a PDF, and attach it to an email. This works for freelancers, small businesses, and most B2B transactions.

Subject Line Best Practices

Your subject line should be clear and scannable. Include the invoice number and your name or business name so the client can find it later.

Good subject lines:

  • Invoice #MC-2026-003 from Maria Chen
  • Invoice #INV-0042 - Web Design Services - March 2026
  • Payment Request: Invoice #2026-0015 from Bright Studio

Avoid: "Invoice" (too vague), "URGENT - Please Pay" (unprofessional), or no subject at all.

Example Email

Subject: Invoice #MC-2026-003 from Maria Chen

Hi Sarah,

Please find attached invoice #MC-2026-003 for the website redesign project completed in March 2026.

Amount due: $3,100
Due date: April 4, 2026

Payment can be made via bank transfer using the details on the invoice. Please let me know if you have any questions.

Thank you,
Maria Chen

Tips for Email Delivery

Method 2: Cloud Sharing

Upload the PDF to a cloud storage service (Google Drive, Dropbox, OneDrive) and share the link with your client. This is useful when email attachment size limits are a concern or when you want to keep a shared folder of invoices for an ongoing project.

Method 3: Accounting Software or Client Portal

If you use accounting software (QuickBooks, Xero, FreshBooks, etc.), you can send invoices directly through the platform. The client receives an email with a link to view and pay the invoice online. Many of these tools also let you download the invoice as a PDF for your records.

For clients who use their own procurement systems, you may need to upload your PDF invoice to their vendor portal. Ask your client for instructions if they use this approach.

After You Send

Use the invoice PDF generator to create and export your invoice, or start from scratch in the invoice editor.

Create and download your invoice PDF