Thanks @Lightning - I just wasn't sure if deposit interest over a certain amount (e.g. €5K) maybe became categorised as income and assessed as such. Does over €5K of deposit interest cause one to become self-assessed? I presume not.USC - No liability.
Income tax - No liability.
PRSI - you are subject to PRSI if your unearned income exceeds €5,000 in a calendar year. AIB pay interest annually with a 2 year term deposit. The interest is approx 4k per year post DIRT but over 5k gross - so you would be subject to PRSI.
Yeah, so good point, that correct post tax formula is probably: 200000*0.0302*2*(1-.37)