Mortgage Interest Relief (Tax Relief at Source - TRS)

How do you claim Mortgage Interest Relief?

You can only claim Mortgage Interest Relief online. This portal should only be used if you are claiming TRS for the year 2020 for the previous TRS scheme which ceased on 31 December 2020.


A new temporary Mortgage Interest Tax Credit was announced in Budget 2024. For further information, please see Mortgage Interest Tax Credit. The online portal referred to above is for claiming Mortgage Interest Relief for 2020. It should not be used for claiming the new temporary Mortgage Interest Tax Credit.

Before you apply, you will need your Personal Public Service Number (PPSN) and details of all previous loans for this property as provided by your lender.

Once online, you can:

  • make a claim for interest paid in previous years (up to the last four years) on this mortgage
  • apply for relief on a top-up to an existing loan
  • amend details if you have moved lenders or switched loans with the same lender, but have not moved home
  • and
  • consolidate two or more loans into one loan secured on your home.

If you are married or in a civil partnership, you may submit your details on one application. In all other cases of joint borrowings, each individual must submit separate online applications.

Once relief is granted, your lender will continue to apply the relief automatically each year.

What to do if there are changes to your mortgage?

You should notify Revenue of any changes to your mortgage.

Examples of changes are if:

  • you top up your mortgage on your existing property
  • you take out a new mortgage
  • or
  • your loan is no longer valid for Tax Relief at Source (TRS).

You should complete TRS4 and return it to the address on the form.

Next: How do you calculate Mortgage Interest Relief?