UK EEA Family Permit
This is a permit applies to the Non-EEA family member or extended family member of EEA Citizen who wants to enter, travel and join in the UK. The EEA family permit is valid for 6 months and holder of this may enter and exit in the UK for such period of time and able to remain in the UK, if you meet the eligibility, criteria and have the permission to do so.
For the EEA national to be eligible, one must be either in the UK for more than 3 months, be qualified person (working, studying, self employed, or looking for work, self employed or self sufficient), or have a permanent right of residence in the UK. The EEA national must also be either travelling with you in the UK within the 6 months from the date of your application.
While for the family member of a British Citizen, as a rule won’t qualify for the EEA family permit, simply because an EEA national cannot exercise his/her free movement rights on their own member State.
However, where an EEA national has exercised a treaty right in another Member State as a worker or self-employed and they wish to return to their own State having exercised that right, certain provisions may apply in order for their non-EEA family members to qualify under the EEA Regulations.
A British national and his / her non-EEA national family members can only benefit from free movement rights if they meet the criteria established in the ECJ case of Surinder Singh. The case stated that nationals of a Member State who are exercising an economic Treaty right (that is, as a worker or self-employed person) in another Member State will, on return to their home state, be entitled to bring their non-EEA family members to join them under EC law.
Example: A British national is exercising an economic Treaty right in Germany and living with his non-EEA national spouse and children. On the British national’s return to the UK, his non-EEA national family members can apply for an EEA family permit to join him under EC law.
Source: Home Office