There are reduced frequency for filing tax returns and paying tax for smaller businesses.
You can pay and file VAT returns twice a year or three times a year instead of normal six times a year if your VAT payments are withing treshold.
You can pay and file P30 returns four times a year instead of twelve times a year if your PAYE/PRSI payments are less than €28,800.
You can pay and file RCT returns four times a year instead of twelve times a year if your RCT payments are less than €28,800.