How to Send an Invoice by Email (With Free Templates)

Creating the invoice is only half the job—you still have to get it into the right inbox with a clear ask. This guide shows how to send an invoice by email the right way: who to send it to, what to attach, subject lines that get opened, and free templates you can paste today. When you need a polished PDF first, FreeInvoiceOnline.com can generate it in minutes.

Key Takeaways

• Email the invoice as a PDF to the person who approves payment (and CC AP when asked).
• Put invoice number, amount, and due date in the subject and the first lines of the body.
• Attach one clear PDF; do not rely on an editable Word file as the official bill.
• Send promptly after delivery—waiting a week quietly delays payment.

Before you hit send: checklist

1. Invoice is complete (number, dates, line items, total, terms).
2. PDF filename is clear: Invoice-INV-2026-014-Acme.pdf.
3. You have the right recipient (approver + AP email if required).
4. PO number is included when the client issued one.
5. Payment methods and due date are visible on the invoice and mentioned in the email.

what every invoice needs

Step-by-step: send an invoice by email

Step 1: Create and export a PDF

Use your template or create a professional invoice online for free → on FreeInvoiceOnline.com, then download the PDF.

Step 2: Write a specific subject line

Weak: Invoice
Strong: Invoice INV-2026-014 from BrightPath — $720 due July 28

Step 3: Keep the email short

Lead with amount, due date, and what the invoice covers. Attach the PDF. Offer one payment path.

Step 4: Send to the right people

If your contact is not Accounts Payable, ask who should be CC’d. Large companies often ignore invoices sent only to a personal inbox.

Step 5: Log the send date

Note when you sent it so reminders are timely, not random.

Free invoice email templates

1) First invoice (standard)

Subject: Invoice {{InvoiceNumber}} — {{Amount}} due {{DueDate}}

Hi {{Name}},

Please find invoice {{InvoiceNumber}} attached for {{ProjectOrService}}.

Amount due: {{Amount}}
Due date: {{DueDate}}
Payment methods: {{PaymentMethods}}

Let me know if you need any changes to the billing details.

Thanks,
{{YourName}}

2) Invoice with PO reference

Subject: Invoice {{InvoiceNumber}} for PO {{PONumber}} — {{Amount}}

Hi {{Name}},

Attached is invoice {{InvoiceNumber}} referencing PO {{PONumber}} for {{Description}}.

Total due: {{Amount}} by {{DueDate}}.

Thanks,
{{YourName}}

3) Deposit invoice

Subject: Deposit invoice {{InvoiceNumber}} to start {{Project}}

Hi {{Name}},

Attached is the deposit invoice ({{Amount}}) to begin {{Project}}. Once payment clears, we’ll confirm the start date.

Thanks,
{{YourName}}

4) Recurring monthly invoice

Subject: {{Month}} invoice {{InvoiceNumber}} — {{Amount}}

Hi {{Name}},

Attached is this month’s invoice for {{Service}}. Amount due is {{Amount}} by {{DueDate}}.

Thanks,
{{YourName}}

5) Soft reminder (3–5 days before due)

Subject: Reminder: Invoice {{InvoiceNumber}} due {{DueDate}}

Hi {{Name}},

Friendly reminder that invoice {{InvoiceNumber}} for {{Amount}} is due on {{DueDate}}. I’ve reattached it for convenience.

Thanks,
{{YourName}}

For a larger library of reminder and overdue wording, see our full email template collection. more invoice email templates

Attachment and professionalism tips

• Prefer PDF over DOCX/XLSX for the client-facing bill.
• Avoid huge image scans; keep files small.
• Do not put bank passwords or full card numbers in email.
• If you include a payment link, place it near the amount due.
• Match tone to the relationship: clear beats clever.

Common mistakes when emailing invoices

Burying the amount

If the total is at the bottom of a long story, payments slow down.

Sending from a personal nickname email with no signature

Use a signature with company name, phone, and billing email.

Forgetting the attachment

It happens. Double-check before send—or use a tool workflow that attaches the PDF for you. free invoice generator

FAQs

How do I send an invoice by email professionally?

Attach a PDF, state invoice number, amount, and due date in the subject and opening lines, and tell the client how to pay.

What should I name the invoice file?

Use a clear pattern like Invoice-INV-2026-014-ClientName.pdf so it is searchable in both inboxes.

Should I paste invoice details in the email body?

Yes—key details in the body plus a full PDF attachment. Some clients need the PDF for AP; others approve from the email.

Is it OK to send invoices through Google Drive or Dropbox links only?

Risky. Many AP teams want an attached PDF. Links can break or get blocked. Attach the file unless the client requests otherwise.

How soon should I email an invoice after finishing work?

Same day or next business day whenever possible. Prompt invoices get paid faster.

Final thoughts

Sending an invoice by email is simple when the subject is specific, the PDF is attached, and the ask is obvious. Use the templates above, CC the right people, and follow up before the due date if needed.

Create a professional invoice online for free → on FreeInvoiceOnline.com, download the PDF, and email it with confidence.