Where a person who occasionally undertakes transactions involving supply of goods or services or both in the course or furtherance of business, whether as principal, agent or in any other capacity, in a State or a Union territory where he has no fixed place of business then such person is required to obtain Casual GST Registration. i.e. Whenever any registered person undertakes some activities in some different states where he does not have fixed place of business then such registered person is liable for casual GST registration in state where he undertakes any transaction.

Registration process for Casual Registration is same as Normal Registration except the following:

• Advance payment is required to be paid on Net Expected Tax Liability. This payment can be done at the time of registration and without advance payment, registration certificate can not be granted
• Address proof will not be required. A letter from Event organiser, hotel, landlord will be sufficient.
• Registration shall be valid for maximum 90 days from the date of registration. A further 90
  days extension can be granted on request basis.

• As we explained above casual registration can be obtained for maximum 180 days (including extension period of 90 days) hence liability for return filing will be only for such specific period.
• Casual taxable person is also required to file monthly or quarterly returns like other registered person hence GSTR 1 and GSTR 3B has to be filed as per due dates.
• Casual taxable person are not required to file GSTR 10 however such return is required to be filed by other taxpayer after cancellation of GST registration.
• If advance payment of tax falls shorts as compare to actual tax liability then additional tax can be paid through GSTR 3B.