How to create an invoice

As an entrepreneur just starting out, it’s important to understand the right way to raise an invoice when it comes time to bill your customer. This article includes all the details about when, how and why invoices are used, and outlines the information needed to create legal, professional invoices.

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What is an invoice?

To put it simply: an invoice is the document required for you to get paid. In other words, when you finish a job and it’s time for your customers to pay, the invoice lays out the goods or services provided.

It’s a commercial document that must meet a series of requirements to be considered a legal invoice. And it’s a pillar of the sales process: a ‘must’ if you’re in the business of selling goods or services of any kind.

Accurate invoices are not only important for helping you get paid promptly, but they’re also pivotal for proper record-keeping, maintaining the financial health of your business and filing accurate tax returns.

How to write an invoice

If you’re reading this, it’s likely that you need to create invoices to send to customers. Whether it’s your first sale or your thousandth, each invoice you create needs to meet the same set of requirements.

While sitting down with a paper and pen might seem the obvious and fast way to write an invoice, we suggest a more modern approach that can save you time, tedious calculations, as well as ensure your invoice meets the most recent regulations. The classics most turn to are Word and Excel, but in fact, these are missing some crucial features.

Invoicing software such as SumUp Invoices makes it easy to create compliant invoices in a few simple clicks. All of the necessary fields are included on your premade invoice template, meaning you will never neglect crucial information. 

In order for your invoice to be valid in the UK, it must meet a certain set of requirements. Each and every invoice you create should include:

  • The name and contact details of your business

  • The name and contact details of your customer

  • A unique invoice number that fits in your invoice number sequence

  • The issue date of the invoice

  • A description of each product or service you’re providing

  • The costs of each product or service

  • Your VAT details, if applicable

  • The date the goods or service were provided

  • The total amount due

This basic set of requirements is common for most countries. However, if you’re located outside the UK, either double-check that your invoices don’t require any extra details or simply use invoicing software that is localised to your country.

Types of invoices

It’s important to understand that there are different types of invoices. Here are the most common types of invoice:

  • Standard invoice: This is your everyday invoice, which is the legal document that accompanies a sale.

  • VAT invoice: A VAT invoice is also a standard invoice, but one that includes VAT details for business to business transactions when both businesses are VAT registered.

  • Proforma invoice: A proforma invoice is essentially a draft invoice that is often used in place of a sale before the full details of the sale have been finalised.

  • Electronic invoice: Also known as an e-invoice, this is an invoice created and sent online that meets a series of security clearances.

  • Amending invoice: We’re all human, and sometimes mistakes are made. An amending invoice corrects a mistake made on a previous invoice.

In addition, HMRC distinguishes between three different types of accepted invoices: full invoices, simplified invoices and modified invoices. Full invoices include standard and VAT invoices. A simplified invoice is for any retail supplies with a value under £250, while a modified invoice can be used for retail supplies over £250.

Who can issue an invoice?

In order to issue an invoice, you must be legally allowed to work under sole trader status before or within 90 days after you begin issuing invoices. In many cases, must register as self-employed.

If your business falls above the current VAT threshold, or if you choose to voluntarily register for VAT, your invoices should always reflect this by including your VAT details, and the appropriate VAT rate should be added to your products or services.

Tips for creating invoices

Here are a couple of closing tips for when it comes to raising invoices:

  • Good organisation is often synonymous with success, so the more organised your invoices are, the more easily you’ll be able to stay on top of your business.

  • Each new invoice should always be reviewed before it’s sent out to your customer, reducing the chance of errors.

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