http://www.eyeonspain.com/blogs/costaluz/1451/legal-tip-69-claims-against-ibi-tax-amount.aspx
If your IBI receipt (Local property tax) over-rises after a Cadastre review, there are two possible avenues of legal action:
A) Before or against the body of cadastral revision.
I. Submitting a Request for review to the Cadastre management organ which corresponds territorially.
The document you will receive with the revision of the Cadastre value needs to mention the address of the office for the claim and the possibility of the claim itself.
II. Directly to the pertinent Court with judicial power on economic acts of the Administration.
In both cases (I and II), the earlier deadline for filing an appeal is 30 working days (it includes working Saturdays and excludes Sundays and public holidays) from receipt of notification of cadastral revision. You need to receive that document by registered mail.
You are obliged to pay the IBI receipt you are challenging even if you are claiming against it.
B) Before the Local Council
The Local Council applies an index to the cadastral value; this determined the IBI tax amount. It is also possible to submit a claim against that index.
Maria