As a VAT registered business you must provide a valid VAT invoice to your customer (or a till receipt with your VAT number).  This enables your customer, if they are a business, to reclaim the VAT on the purchase they have made.  The VAT invoice is the primary evidence to support the reclaim of VAT.

Valid VAT invoice

A valid VAT invoice must be issued within 30 days of the date of supply and must:

  • have a unique sequential number 
  • show the time of supply
  • have the date of issue of the invoice (if different to the time of supply)
  • have the name, address and VAT registration number of the supplier
  • have the name and address of the person to whom the goods or services are supplied
  • have a description sufficient to identify the goods or services supplied
  • for each description, show the quantity of the goods or the extent of the services, and the rate of VAT and the amount payable, excluding VAT, expressed in any currency
  • have the gross total amount payable, excluding VAT, expressed in any currency
  • the rate of any cash discount offered
  • the total amount of VAT chargeable, expressed in sterling
  • the unit price
  • the reason for any zero rate or exemption

If you are issuing an invoice to a business outside of the UK you must precede your VAT number on your invoice with GB.

If you are providing an invoice to a non VAT registered business then your invoice does not have to include all of the above, however, as a newly VAT registered business can reclaim VAT on stock they purchased within the four years prior to VAT registration which they still hold, it would make sense to always provide an invoice in the same format.  

Non valid documents

As a VAT registered business, if you have an invoice which doesn't contain your business name, your address and the supplier's VAT number, as well as the detail of the purchase, you cannot reclaim VAT on that invoice.  You also cannot reclaim VAT on a proforma invoice, an order, a delivery note or a statement.  So it is really important to always check that you have been given a valid VAT invoice (or till receipt) whether you are VAT registered or not.

If the invoice you have been given is incorrect and you have paid less than the invoice amount you can only claim VAT on the amount you have paid.

HMRC VAT Enquiry

You are required to store all your documents supporting your VAT claim in a way that you can access them easily if requested to do so by HMRC during a VAT inspection.  if HMRC open an enquiry into a particular VAT return (usually a repayment claim that is unusual or soon after becoming VAT registered) they will request 5 documents with the largest VAT element to be sent to them.  At this point you may find that you have claimed VAT on a purchase which doesn't have a valid VAT invoice.  Your VAT claim will be rejected unless, of course, you have sufficient time to request a replacement from your supplier and they are willing to provide you with it.  If it is too long ago they may not be able to.  You may receive a penalty for claiming VAT in error.

Summary

There is a lot of information about VAT on HMRC website which will provide further information and guidance.