Your Employer Annual Reconciliation Declaration (EMP501) for the period 1 March 2018 to 28 February 2019 is due on or before 31 May. This relates to your monthly EMP201 declarations and IRP5s, IT3(a)s etc generated.
Secondly the Department of Labour has extended the date for the submission of your 2018 Return of Earnings to the Compensation Commissioner to 31 May.
As it is important to get both returns totally accurate, ask your accountant for help in any doubt.
Disclaimer: The information provided herein should not be used or relied on as professional advice. No liability can be accepted for any errors or omissions nor for any loss or damage arising from reliance upon any information herein. Always contact your professional adviser for specific and detailed advice.