Gross vs Aer for non Dirt pensioner

Hope I'm posting this in the correct place!
As a non dirt paying OAP I'm looking to invest 20000 and am comparing accounts in permanent tsb.
If I leave it in (Term Deposit) for 5 years the gross is 11.75% and the AER is 2.25%.
However the AER is the same for a few other accounts with a shorter term but the gross is much smaller (4.38% for 2 years interest first and 6.9% for a 3 year term deposit)
I know I'm supposed to go for the higher AER but since I'm not paying dirt and can leave it for 5 years should I go for the higher gross.

Thank you so much to anyone who replies
Mollyo

IF all things stay the same, the 5 year term deposit is a better return.

However, you have to consider what might change in the 5 years.

If the DIRT exemption is removed (back in 2008 I recall some politician saying the OAP exemption would be gone within 4 years) you would be taxed on the total interest when received in 5 years time. You don't know what that tax rate would be.

If the interest rate were to increase in the next few years your 5 year term would not look such a good bet.
Mind you, if interest rates continue to fall over the next 5 years, you would be patting yourself on the back.

Thanks for that Gervan
So if I put it in for 2 years at AER 2.5% and reinvest again then do you think it would be better? But the gross is less here so what difference does that make??
mollyo

Thanks for that Gervan
So if I put it in for 2 years at AER 2.5% and reinvest again then do you think it would be better? But the gross is less here so what difference does that make??
mollyo