Invoice - What is invoicing?

An invoice is a document that a business sends to a buyer. It lists the products and services that the business has provided the client. When an invoice is sent to a customer, it acts as an official request for payment for these products or services. 

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Invoices establish an obligation for the customer to pay the business within a certain time frame. An invoice should contain payment terms that specify how long the buyer has to send payment to the seller, and how that payment should be received.

Invoicing is essential for small businesses. These documents enable companies to get paid by their customers and keep track of their sales. Invoices also help clients  to document their expenses in itemised lists and keep records of what they have paid for. 

Invoicing software makes it easy for businesses to create and send invoices. With online invoice templates, a business can invoice a client in a matter of seconds, without needing to repopulate the same information each time. Creating invoices with invoicing software makes it even easier to notify customers that a payment is due.  

What an invoice should include

An invoice provides a detailed account of the products or services, along with other mandatory information. These mandatory invoice fields can vary depending on the requirements in the country the invoice is issued and the type of product or service being sold.

To be considered an official document in the UK, the invoice should include: 

  • The word ‘Invoice’

  • The name and contact details of the seller

  • The name and contact details of the buyer

  • A unique reference number, commonly known as an invoice number

  • The date the invoice was sent

  • The date the product was sent or delivered (or the date the service was rendered)

  • A line detailing the product/service

  • The cost per unit of the product (if this applies)

  • The terms of payment (detailing the means of payment, when the sum should be received, any cash discount details for early payment, late payment fees, etc.)

  • The total amount that is owed

Invoicing in SumUp Invoices

With SumUp Invoices, you can create, send and enter payment on your invoices from your computer, smartphone or tablet.

Our easy-to-use invoice templates make it simple to create professional invoices in just a few clicks. Add your company logo to customise your invoice and promote your unique brand. 

Read more about invoicing with SumUp Invoices: “Getting started with SumUp Invoices”. 

Why invoicing is important

Invoices are a fundamental part of communicating with a client during the sales process. It’s the main document that serves as a bill for the service or products your business has provided. Issuing invoices helps to speed up the payment process by notifying the client that a payment is due and setting a deadline. 

A finalized invoice establishes an obligation that the client pays the business for products or services that have been rendered. Therefore, invoices can be used in the event that a payment is overdue or missing. As a formal request for payment, an invoice can support the formal actions that can be taken against a debtor to demand payment. 

Explore the different ways of managing overdue payments: “How to manage overdue invoices”.

Invoices also help clients organise their expenses. In B2B sales, the invoice provides an organised record of their expenses with itemised details and VAT (if applicable). It therefore helps them with their own record keeping.  

Sales vs. purchase invoice

Invoices detail what a buyer owes to a seller. From a seller’s point of view, an invoice for the sale of goods and/or services is referred to as a sales invoice

From a buyer’s point of view, an invoice for the cost of goods and/or services rendered is referred to as a purchase invoice.

Invoicing online

Today, there are many types of online invoice software that make it easy to create and send invoices. Cloud-based online software like SumUp Invoices is available at any time, anywhere you have an internet connection and smartphone, tablet or computer.

Good invoicing software provides invoice templates that adhere to the legal requirements as well as VAT for an invoice in the country in which your business is based, meaning that there are no concerns about whether you've included all the details your invoice needs.

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