Portugal residency permits for EU-nationals and their NON-EU families under article 15/37. Register in portugal as an Eu national with the city council of your resident area to obtain a five-year registration certificate.
Further, demonstrate income in Portugal for at least six months to invite non-Eu families in portugal under the EU treaty.

Few steps have been flowing as below.
Step-by-Step Process
STEP-1 Book an appointment with the municipal council
Book an appointment with municipal council Portugal Câmara Municipal competent authority to register for European Union, EEA, ANDORRA, and SWITZERLAND nationals who wish to stay in Portugal for more than 90days. Before collecting a certificate of registration, request an online appointment area of residence.
STEP-2 Prepare needful documents
Carry among yourself during the visit for the collocation of the registration certificate.
European passport identity card
Portuguese tax number
Portuguese accommodation proof
Portuguese bank account
Activity proof subject to demand
STEP-3 Visit for the collection of certificate
The registration certificate will be handover to you physically during the day of the appointment, which will be valid for the next five years. The certificate protects permanent residence of Portugal latter five years being citizenship subject to ensuing certain conditions.
STEP-4 Residence card for families of EU-Nationals
Portugal, followed by EU law, protects families of all EU nationals under article 15/37. Family members are nationals of third-country (NON-EU) and intend to accompany a family member who is an EU/EEA/Switzerland citizen request for a residence card at the SEF office (Immigration Services Portugal).
Spouse
Dependent children
Parents
STEP-5 Establish commercial in Portugal
Before moving visa or residence requests for non-EU families to the competent authority, demonstrate your association & commercial connection with Portugal.
Professionalism
Sufficient financing
STEP-6 Prepare needful documents
Before moving visa or residence requests for non-EU families to the competent authority, collect appropriate documents.
Valid Passport of EU-national
Registration certificate
Valid Passport of non-EU family
Relationship documents
Professionalism documents
Sufficient financing or income
Portuguese tax numbers
Accommodation contract
Criminal record non-EU family
State responsibility form
STEP-7 Apply visa EU-family visit
Request for EU-family visits visa at Portuguese consulate of your non-EU family members resident or home country onward among supporting documents. Perhaps your country is exempt from visa permission, or your family already have a Schengen visa.
STEP-8 Book an appointment with SEF
Book an appointment with (SEF) by telephonic call as per your connivance time and date along with location subject to availability under article 15.
STEP-9 Visit SEF for fingerprints
The applicant obelised to report Portugal immigration authority (SEF) with appropriate documents translate into Portuguese on the appointment day.
STEP-10 Collection of residence card
The residence card will deliver to your Portuguese home address by post, which will be valid for the following five-under articles 15/37 as an EU-family member.
For more information, Download PDF – Registration certificate Step-By-Step procedure

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