All businesses registered under GST have to file monthly, quarterly and/or annual GST Returns based on the type of business. A return is a document containing details of income which a taxpayer is required to file with the tax administrative authorities. This is used by tax authorities to calculate tax liability.Under GST, a registered dealer has to file GST returns that include Purchases, Sales, Output GST (On sales), Input tax credit (GST paid on purchases). To file GST returns or GST filing, GST compliant sales and purchase invoices are required. GST Return Filling is a critical activity that acts as a link between the government and the taxpayer. Once the GST Registration is done, it is the responsibility of the taxpayer to file the GST Return.