There are certain requirements regarding the content of an invoice, which includes:

• a sequential number based on one or more series which uniquely identifies the document
• the time of the supply (tax point)
• the date of issue of the document (where different to the time of supply)
• Supplier name, address and VAT registration number
• the customer name and address
• a description sufficient to identify the goods or services supplied
• for each description, the quantity of the goods or the extent of the services, the rate of VAT, and the amount payable excluding VAT
• the gross total amount payable, excluding VAT
• the rate of any cash discount offered
• the total amount of VAT chargeable
• the unit price

In case a VAT invoice includes zero-rated or exempt supplies, those items clearly have to show that there’s no VAT payable and a separate total for their values have to be indicated as well. It is also possible to issue simplified VAT invoices if the value of goods is less than £250 and the customer also agrees to have a simplified invoice for the items.