Firstly, the changes are for the 2015 tax year. The tax due next June is not affected. It will be your declaration in June 2016 where it first affects you.
The changes have not been confirmed yet. You can get more info here
http://www.blevinsfranks.com/News/Blevi ... icleID=643
What that doesn't tell you is that the personal allowances have gone up to €5050 and an additional €1150 over 65 and another €1400 over 75.
The "general allowance, which is currently €4080 - €2562 is changing to €3700 on income below €11250 and between €11250 and €14450 it reduces to zero. That is not good news for the many people who have income above €14450 but there appears to be another allowance introduced of €2000 which goes some way of rectifying the loss of the general allowance.
However, at the moment it is not clear exactly who will benefit from this new allowance. The law refers to it being for "trabadores" and it is not clear exactly what they mean by that. My feeling is that it will apply to everyone except those with just saving income. If not, it would mean that the average Spanish state pensioner would be worse off and I am sure that is not what the government intends.
If you want to get a real headache you could try making your own assessment by looking at the details at
http://www.minhap.gob.es/Documentacion/ ... 20IRPF.pdf
Sid