A guide to self-assessment

Pay and file system - how does it work?

By 31 October in a tax year, you must:

  • pay your preliminary tax for that year
  • file your tax return and self-assessment for the previous tax year
  • pay any balance of tax due for the previous year.

For example, by 31 October 2021 you must:

  • pay your preliminary tax for 2021
  • file your 2020 self-assessment tax return
  • pay any Income Tax (IT) balance for 2020.

When you pay and file through the Revenue Online Service (ROS), the 31 October deadline is extended to mid November. The due dates for Capital Gains Tax (CGT) are different to those for IT. To avoid interest charges, please ensure you file by the correct due date.

You can amend any errors on your tax return through ROS. If you have filed a paper copy, please contact your Revenue Office to make any necessary amendments to your return.

You will have to pay a surcharge if you send your tax return after the deadline, as follows:

  • within two months of the filing date: 5% of your tax due, up to €12,695
  • over two months: 10% of your tax, up to €63,485.

Note that even if you pay and file on time for IT, a 10% surcharge may apply if your Local Property Tax (LPT) obligations are not met.

Next: What forms do you need to complete?