For VAT reg business you will need to provide ONE of the following: a Vat certificate with company name and VAT number CLEARLY VISIBLE on the document OR a business invoice with VAT number CLEARLY VISIBLE on the document. For NON-VAT business, please provide ANY of these documents: Business invoice (recent up to 3 month) with Business Name and address, or Tax registration certificate, or Sole trader/Self employed registration certificate. The document must clearly display your company name and business address. If you are concerned about sharing your client's details when sending a business invoice, you can block out their details leaving only your Company Name, Address and VAT number clearly visible to us.