You have to be a tax resident in Spain to get an 80% mortgage.
However, there is unfortunately no exact amount of time indicated by the banks in which you have to have lived and paid taxes in Spain to get access to a residential mortgage of 80%. In our experience we find that at least six months of provable tax history is necessary to apply for an 80% mortgage.
If you have a Spanish tax return it is obviously better, but a residential mortgage can be granted without being in possession of a Spanish tax return.
The decision to grant a residential mortgage is taken on a case-by-case basis by the banks with other criteria taken in to consideration.
Therefore it is a good idea to contact us if you want to determine whether you are eligible for a residential mortgage of 80% or not.