As the header on a document file, the header of an invoice is the space at the top of the invoice. In many cases, you want to have the word ‘invoice’ written boldly on the header of an invoice. This technique allows anyone that comes across the document to know that the material is an invoice. As such, it simplifies document filing and general procurement processes.

Create Invoice Header Web API provides nice templates for your invoices, and converts from HTML to PDF!

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You may want to include your company’s information alongside the word ‘invoice’ on the header. Nowadays, almost all companies use specialized software to edit and create unique headers as preferred. As such, it is wise if you can use such a type of software.

The header of an invoice is created in several different formats. These formats are given as follows.

Type 1

For this type, you would write the word ‘invoice’ within the header. You will immediately write the name of your company below with its various addresses, telephone numbers, fax, email address, and other contact information. A wide range of companies commonly uses this format. Usually, you would center your company’s information in the middle of the invoice. Depending on your preference, you may choose to include your company logo.

Type 2

The type 2 header usually contains the logo and the company’s information on the header of the invoice. You would often input your company’s logo to the left, while its information is aligned to the right. You would usually find the word ‘invoice’ written in the middle. The company information typically includes company name, address, and contact details.

Type 3

The type 3 header is similar to the type 2 invoice. The main difference between the two is that you input the logo to the right, while the company’s information is written to the left. As usual, the word ‘invoice’ is written at the center.

Invoice Header Details

Irrespective of the header format you choose, the data and information you include in the header must be accurate. A third party should be able to read and understand it easily and be able to verify it if necessary.

In that regard, here is an overview of the details commonly included in the invoice header.

Invoice Number

An invoice number is a unique number on the invoice header, often matched with a purchase order. You can use it to identify an invoice that you have issued to your customers, as well as for accounting purposes.

You can generate it automatically using invoicing software such as ours, or generate it manually. What is important is that no two invoices from your business should have identical invoice numbers.

External Reference Number

This can be a number that a customer sent you when ordering a product or service. This number is often important when you contact the customer about issues related to that invoice.

It can be manually generated or automatically generated. Some invoices will have an external reference number, in addition to the Purchase Order number. You cannot change this number.

Invoice Date and Time

This is the date and time that you generated the invoice, and it’s best practice not to change. Instead, you can create an updated invoice with a new date, and add a description of the changes made, in the body of the invoice.

Last Print Version

You can have a “Last Print Version”, to indicate the date that you sent a manual copy of that invoice.

Invoice Type

An invoice can be created by the supplier or by the customer. If the business creates it, its type is just “invoice”. However, if the customer creates it, it becomes a “Self-billing” type of invoice.

As a business, a customer can only send you a “Self-billing” invoice, if you have agreed to such a business arrangement.


You can group your invoices into group categories for easy management. If you do, then you can specify the invoice’s group in the header. Group the invoices helps to sort and invoices, especially for large businesses, that handle millions of sales daily.

Acceptance Status

Often a customer may reject or accept an invoice, at any point of the invoice status. The acceptance status is indicated as either “Accepted” or “Rejected”.

Invoice Status

The status of the invoice indicates the accounting stage of that invoice. This can be as simple as “Viewed”, “Partial”, or “Paid”. If the customer has paid for the goods or services, the invoice status is “Paid.”

“Viewed” is when the customer has only viewed the invoice but hasn’t paid for it, while “Partial” is when the customer has paid in part for the invoice. You can use automated invoicing tools such as ours, to create invoice status.


You can have a validation status on the invoice header. It’s best practice to have an invoice validation mechanism. That protects your customers from receiving invalid invoices from scammers.

Having that information on the header also helps your fraud department to stop invoicing fraud in its early stages. Web API converts from HTML to PDF, and provides nice templates for your invoices!

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