As per Notification 36/2020 CT Last Date to file May -20 GSTR 3B :
Taxpayer Turnover more than 5 crore : 27/6/2020
Taxpayer Turnover less than 5 crore & principal place of Business is in state of Chhattisgarh, MP, Gujarat, Maharashtra, Karnataka,goa,keral,TN, Telangana,AP,Puducherry,andman,UT of Daman & Diu & Dadar & Nagar haveli is 12 /7/2020
As per Notification No. 36/2020 - Central Tax, dated 03rd April 2020, the last date to file FORM GSTR-3B for the month of May 2020 without Late Fees and Interest for the Taxpayers having Aggregate Turnover more than Rs. 5 crore is "27th June 2020."