@WizardDr Thank you for seeking and obtaining a response from Revenue. In another thread I said the following, which
@James5 linked to in this thread :
In the meantime I have gone back through my files to see how I came to form this opinion. The explanation is as follows:
In the middle of the last decade, for a number of years I had rental income which required me to complete a Form 11. This was actually completed and submitted by my accountant on my behalf. During that period I had deposit interest (well below the €5,000 threshold) which was declared on the Form 11. When I received the draft Form 11 from my accountant for approval prior to submission I queried the sum due to revenue, as it varied by a small amount from the liability I had calculated based on my rental income. His explanation was that the PRSI due on the deposit income was the cause of the discrepancy. On further querying it with him, he described it as an anomaly, and said that DIRT at the prevailing is treated by Revenue as full and final settlement (with no PRSI charged) where it is charged by the bank or financial institution and where a Form 11 is not otherwise required. However, where a Form 11 is completed, for whatever reason, the deposit interest becomes liable for PRSI.
As is often the case with anomalies it does appear unfair, however it would be impractical for Revenue (and the banks and financial institutions that operate DIRT collection on their behalf) to collect PRSI, unless it were rolled into the basic DIRT rate and applied across the board subject to the same rules as DIRT generally. This would then penalise those under 18 and those over 66 who are liable to DIRT, replacing one anomaly with another.
The position in relation to Form 12 is a lot less clear. Certainly, deposit interest does have to be declared on Form 12 if that is being completed for any reason. Whether or not a Form 12 is required to be completed because of deposit income alone is the question. It appears to me that those who complete the form and declare depots interest will pay the PRSI "penalty", whereas those who don't bother are unlikely to be detected or pursued.