When is the due date for filing it return for ay2018-19(fy2017-18) , is it 31july or 31 august 2018?

when is the due date for filing IT returns for AY2018-19(FY2017-18) , is it 31 july or 31 august 2018 ? as per income tax website the due date is extended to 31-August-2018 , is it applicable to me ? I have income only from bank interests ( no other income) Please suggest whether I need to file IT returns by today (31 July) or can file by 31-August ?

Thanks

Josh