GSTR 3A is not a return form, but a notice form issued by the government to taxpayers who have failed to file their GST returns on time. It is a system-generated notice that is issued to taxpayers who have failed to file their return in Form GSTR-3B or any other returns within the due date. The notice is issued to taxpayers who have not filed their GST returns, including monthly, quarterly, and annual returns, as notified by the Central Board of Indirect Taxes and Customs (CBIC) . The notice is issued to taxpayers who have not filed returns such as GSTR-3B (Regular dealer), GSTR-4 (Composition dealer), GSTR-5 (Non-resident Taxpayers), GSTR-6 (Input Service Distributor), GSTR-7 (TDS Deductor), GSTR-8 (TCS collector), GSTR-9 (Annual return), and GSTR-10 (Final return) . Upon receiving the notice, the defaulter has to file the return within 15 days from the date of notice along with penalty and late fees.