Papers in order
If you don’t have a VAT receipt, you’re not supposed to claim the VAT on an expense, even if it’s a proper business cost. The rule is there because HMRC want to be confident that the supplier has paid the VAT over to them – they want to see a bit of paper with the supplier’s VAT number on it, so they are sure they’re registered and can follow it up if necessary.
What if you are sure that the supplier is registered, but they won’t give you a VAT receipt? Some big businesses which deal mainly with the public don’t like issuing full invoices, so they try to brush people off – mobile phone networks and utility companies are examples. Sometimes the supplier has a point – if you’re a business customer, you may have to pay a higher tariff, so it might be better to keep quiet and not worry about the VAT.
Someone discovered recently that Amazon won’t issue a VAT invoice for a Kindle, because your agreement on buying the Kindle (who reads those before ticking them?) says that you won’t use it for business purposes. The law says that they have to issue a VAT invoice to a VAT registered person who asks for one, and it’s then up to the customer to claim or not according to business use – but it’s hard to have an argument with such a big company.
In some circumstances, it’s legal to claim input tax without a VAT invoice if you can show HMRC that the supplier was registered and you definitely incurred the expense – they can accept alternative evidence, and they shouldn’t refuse unreasonably. But bear in mind that your files of VAT invoices are one of the first things that a visiting officer will look through – claiming without the right paperwork risks an argument at best, and a cost at worst.