Under the GST regime, an “invoice” or “tax invoice” means the tax invoice referred to in section 31 of the CGST Act, 2017. This section mandates the issuance of an invoice or a bill of supply for every supply of goods or services. It is not necessary that only a person supplying goods or services needs to issue an invoice. The GST law mandates that any registered person buying goods
or services from an unregistered person needs to issue a payment voucher as well as a tax invoice.
The type of invoice to be issued depends upon the category of registered person making the supply. For example, if a registered person is making or receiving supplies (from unregistered persons), then a tax invoice needs to be issued by such registered person. However, if a registered person is dealing only in exempted supplies or is availing the composition scheme (composition
dealer), then such a registered person needs to issue a bill of supply in lieu of invoice. The invoice should contain description, quantity and value & such other prescribed particulars (in case of supply of goods), and the description and value & such other prescribed particulars (in case of supply of services). An invoice or a bill of supply need not be issued if the value of the supply is less than Rs. 200/-, subject to specified conditions.