As a one-time measure to enable taxpayers to clear the backlog of all GSTR-1 which have not been filed from July 2017 to Nov 2019, a late fee waiver till 10.01.2020 (vide NN 74/2019 dt. 26.12.2019) has been provided.
After 10.01.2020 a late fee of Rs. 25 per day(under CGST Act) and Rs.25 per day(under SGST Act) read with vide notification no. 04/2018 Central Tax for non-filing of GSTR-1 up to a maximum of Rs.10,000 under both CGST and SGST Act per statement will be levied as per existing provisions. Therefore, the taxpayers are requested to file all GSTR-1 return on or before 10.01.2020.
Further, the Government plans to take a number of steps if the pending GSTR-1 are not filed by 10.01.2020 such as blocking of E-way bill, etc.
Also, it is beneficial for the recipients to encourage their suppliers to file their GSTR-1 in time as it is important that the credit taken by the recipients in their GSTR-3B matches with the details auto-populated in their GSTR-2A
For your reference:Notification No. 74/2019-Central Tax