late fee

yes, similar to late fees applicable in case of delayed filling of GSTR3B. 

20per day in case of nil return

50 per day in other case 

 late fees of Rs. 

•  50 per day of delay in normal cases
• Rs. 20 per day of delay for taxpayers having nil tax liability for the month

The GST Council has waived late fees for GSTR-3B for July, August, and September. Any late fees paid for these months will be credited back to the company’s electronic cash ledger under ‘Tax’ and can be utilized to make future GST payments. 

Interest on delayed tax payments is charged at 18 percent per annum on the amount of outstanding tax and is calculated from the day following the missed due date until the actual date of payment.
 

Rs. 50 and 20 is for 3B and 4

For rest GSTR:

late fees of Rs. 100 per day per return will be levied on companies in cases of late filing. This means total late fees of Rs. 200 per day (100 under CGST and 100 under SGST), subject to a maximum of Rs. 5,000 for a particular period. There are no late fees for IGST returns.
 

Yes, i agree with Rs.50 and Rs.20.

The above reduced revised fees is from 7th March 2018.