What is a Tax Invoice?

A tax invoice is an invoice issued by a registered dealer to the purchaser, showing the amount of tax payable. A retail invoice is an invoice issued by the seller to the buyer for the amount due against the goods sold to him.

Under GST Act-

(1)A registered taxable person supplying taxable goods shall, before or at the time of,-

(a) removal of goods for supply to the recipient, where the supply involves movement of goods, or

(b) delivery of goods or making available thereof to the recipient, in any other case,

issue a tax invoice showing the description, quantity and value of goods, the tax charged thereon and such other particulars as may be prescribed.

(2)A registered taxable person supplying taxable services shall, before or after the provision of service but within a period prescribed in this behalf, issue a tax invoice, showing the description, value, the tax payable thereon and such other particulars as may be prescribed.

PROVIDED that the Central/State Government may, on the recommendation of the Council, by notification, specify the categories of goods and/or supplies and/or services in respect of which the tax invoice shall be issued within such time as may be prescribed.

Sources: https://www.quora.com/What-does-a-tax-invoice-mean