Revocation of Cancellation/Suspension GST No.

A GST registration can be cancelled by 
*The taxpayer himself
*GST officer
*A legal heir of the taxpayer in case of death of proprietor

Reasons for GST Registration Cancellation
As per Section 29 of the CGST Act, the taxpayer can apply for the cancelled GST registration under the following cases:

1.The business has been discontinued (reason may be the death of the proprietor, transfer of business in form amalgamation, demerger etc.)
2.Change in constitution of business
3.GST Registered person is not mandatorily, liable to get registered under GST (reason may be turnover of business goes below the threshold limit)
4.When GST Registered person contravenes the provisions of the Act
5.When GST Registered person does not file his GST Return
6.When GST Registration has been obtained by means of fraud, willful misstatement or suppression of facts
7.When a person takes Voluntary GST Registration and after registered under GST, does not commence business within 6 months from the date of GST Registration, then GST Officer has the power to cancel the GST Registration

Final Return u/s. 45:
As per section 45, “every registered person who is required to furnish a return under sub-section (1) of section 39 and whose registration has been cancelled shall furnish online on the GST Portal, a final return “within three months” of the date of cancellation or date of order of cancellation, whichever is later, in GST FORM GSTR-10 as specified in Rule 81” otherwise assessee need to pay fine 200 rs. per day after expiry of 3 month.

Revocation of cancellation of registration

If GST Registration of any registered dealer is cancelled by officer by his own motion, the registered person has the option to apply for Revocation of Cancellation 
of registration, which is governed by Sec-30 of CGST Act, 2017. If we want, Revocation of cancellation of registration, then we have to submit our application in 
FORM GST REG-21 to GST Officer within 30 days from the date of service of the cancellation order.

Imp.:.No application for revocation shall be filed, if the registration has been cancelled for the failure of the registered person to furnish returns unless such 
returns are furnished and any taxes due have been paid.

Who All Cannot File the Cancellation of GST Registration?

Taxpayers registered as Tax deductors / Tax collectors
Taxpayers who have been allotted UIN

Forms used to cancel GST registration:

GST REG 16: applicable when the taxpayer himself applies for the cancellation of registration.

GST REG 17: An authorized GST officer can provide the notice of show cause to the registered taxpayer and its business entity by using the REG 17 form. 

GST REG 18: The show cause notice can be replied by the means of furnished GST REG 18 form.

GST REG 19: The GST REG 19 form is for the usage of GST officer for issuing a formal order for the cancellation of GST registration. 

GST REG 20: The show cause notice when satisfied by the GST officer can direct for the revoke of any proceedings towards the cancellation of the registration and he should pass the order in the Form GST REG 20.