How to Create a Professional Invoice
A complete walkthrough of creating a professional invoice — from business details and customer information to line items, VAT, payment terms and record keeping.
Creating an invoice for the first time can feel daunting
If you have just started a business or gone self-employed, creating your first invoice can feel overwhelming. What information do you need to include? How do you number it? What should the payment terms say? How do you send it? What records do you need to keep?
Getting it wrong is not just embarrassing — it can delay payment, cause confusion with your customer, and create problems if HMRC ever asks to see your records.
The good news is that a professional invoice follows a clear structure. Once you know what to include and in what order, creating one becomes a two-minute task rather than a twenty-minute struggle.
A step-by-step guide to creating an invoice
A professional invoice includes seven key sections: your business details, the customer details, the invoice number and dates, the line items (what you are charging for), the totals (subtotal, VAT, total), the payment details (how the customer should pay), and any notes or terms.
Start by adding your business name and address at the top. Then add the customer name and billing address. Assign a unique invoice number — sequential is best (INV-001, INV-002). Add the issue date and a due date. List each product or service with a description, quantity and unit price. The subtotal, VAT and total are calculated for you. Finally, add your bank details and any payment terms.
MileageCalendar walks you through each of these steps with a guided invoice creator. You fill in the fields, see a live preview, and download a professional PDF when you are done. You can also add mileage and expenses — something most invoice tools do not support.
Business details
Your business name, address and contact information at the top of the invoice.
Customer details
The name and billing address of the customer you are invoicing.
Invoice numbers
A unique, sequential number for every invoice — so you and HMRC can track them.
Line items and pricing
A clear description of each product or service, with quantity and unit price.
Taxes and totals
Subtotal, VAT and total amount due, calculated automatically.
Payment terms
When payment is due and how the customer should pay — bank details, due date.
Notes
A thank-you message or any additional information the customer needs.
Record keeping
Every invoice is saved and searchable, so you have a complete record for HMRC.
How it works
Add business and customer details
Enter your business name and address, then select or add the customer you are invoicing.
List your line items
Add each product or service with a description, quantity and price. VAT and totals calculate automatically.
Set payment terms and send
Add your bank details, specify when payment is due, then download a PDF or email it to your customer.