Bill of supply: A bill of supply is required to be issued in the following cases:
a. Where the supplier is a registered person who has opted for composition of tax under section 10 of the Act (and shall not charge tax on the bill of supply); or
b. Where the goods / services being supplied by any registered person are wholly exempted.
The bill of supply is required to contain all the applicable particulars as are specified in Rule 49 of CGST Rules, 2017