Invoice fundamentals
To send an invoice, review every field, export a clear PDF, write a short message, use the agreed delivery channel, confirm receipt and track the due date.
Create and download an invoice
Review the Invoice Before Sending
Read the finished document as the customer will see it. Confirm it matches the agreement and contains no private notes or unfinished placeholders.
Verify Customer Details
Check the legal or trading name, billing address, contact person, accounts-payable email and purchase-order reference where applicable.
Check Invoice Number and Dates
Confirm the identifier is unique and the invoice date, terms and due date agree.
Check Calculations
Recalculate quantities, rates, subtotal, discount, applicable tax, payments already received and balance due.
Pre-Send Checklist
- Seller and customer details checked
- Invoice number is unique
- Dates and terms agree
- Line items and totals checked
- Currency and payment method stated
- PDF opens and filename is clear
- Recipient and attachment checked
Export the Invoice
PDF is useful for preserving layout. Use a descriptive fictional filename such as invoice-INV-0042-northstar-studio.pdf and open the export before sending.
How to Email an Invoice
Attach the correct file, address the right person and keep the message brief. Do not place unnecessary confidential information in the subject line.
Invoice Email Subject Line
Fictional example: Invoice INV-0042 from Northstar Studio, due 2 September 2026.
Invoice Email Message Example
Hello Alex,
Please find attached invoice INV-0042 for the fictional August design project. The balance is USD 1,250 and the due date is 2 September 2026. Payment instructions are on the invoice.
Please let me know if the attachment does not open or if your accounts team needs another reference.
Thank you,
Sam
Northstar Studio
This example is fictional. Replace every detail and verify the message before sending.
Email vs Client Portal
Email is direct and familiar. A portal can provide structured submission and delivery records. Use the channel the customer approved, including mandated e-invoicing where applicable.
Confirming Delivery
Watch for bounced email or portal rejection. For an important invoice, request a simple acknowledgement without repeatedly contacting the customer.
Record Keeping
Keep the final invoice, delivery record and relevant correspondence according to your business and local retention requirements.
Tracking the Due Date
Add the invoice number, customer, amount, sent date, due date and status to a register or calendar.
Following Up
Send a polite reminder that identifies the invoice, amount and due date. First check that it was received and that no correction is pending.
Correcting an Invoice After Sending
Tell the customer promptly. Preserve the original record and issue the appropriate corrected or replacement document under your local rules.
Frequently Asked Questions
Should I send an invoice as a PDF?
PDF is often practical because it preserves layout, but use any format or channel the customer and applicable rules require.
What should an invoice email say?
Identify the invoice, amount, due date and attachment, then invite questions.
How do I know the invoice arrived?
Check for delivery failures or portal status and ask for acknowledgement when appropriate.