Important news: the PP party proposes raising the language requirement to B2 in its programme. Keep in mind that this is a party programme, not a law.
How to apply. You file the application online with the Ministry of Justice. You will need:
- birth certificate;
- criminal record certificates with an apostille and translation;
- valid residence card and padrón;
- exam certificates.
By law, processing takes one year; in practice it takes one year to eighteen months. If you get no answer within a year, the application counts as refused through administrative silence. After a positive decision, you must take the oath within the set deadline, register your citizenship, and only then get your Spanish documents.