The UK government website is recommending that UK citizens resident in Spain apply for their TIE card immediately.
While it is not a legal requirement, in that the green certificate is recognised as proof of residency, it does mean your right to reside is easily recognised and will make your administrative live much easier.
There is also evidence that the legality of the green residency certificate has not filtered down to everyone and administrative offices, immigration officials and even banks are refusing to accept it.
It is a simple procedure and everyone with the green residency certificate is advised to change it for a TIE without delay.
Non-residents in Spain, who are subject to the 90 day rule, are advised to get their passport stamped when entering and leaving Spain. Failing to do so may result in immigration officials refusing to allow you to enter or even attempting to fine you as an over stayer when you leave Spain.
