Each family member files their own Form 149. There is no joint application, and a family member can only apply the regime if the primary taxpayer does too.
Deadline: six months from the family member's date of entry into Spain, or the primary's deadline if later (art. 116 PIT Regulations). Keep evidence of the entry date: tickets, passport stamps or rental contract.
Documents per member: passport and NIE, marriage certificate or children's birth certificates, tax residence certificates for the five preceding years and proof of entry date. AEAT issues the document confirming the election within ten working days.