With the entry into force of the Withdrawal Agreement (the Agreement on the withdrawal of the United Kingdom of Great Britain and Northern Ireland from the European Union and the European Atomic Energy Community) on 1st February 2020 the transition period started which will last until 31st December 2020. During that period, the rules of residence and work of citizens of the United Kingdom and their family members in Poland remain unchanged. This means that the free movement of persons between the UK and the EU is maintained during that period.
During the transition period United Kingdom nationals may arrive to Poland and start their residence on the same rules as before the date of exit of the of the United Kingdom from the European Union.
In accordance with the Withdrawal Agreement after the end of the transition period citizens of the United Kingdom and their family members will have the right of residence in Poland if they exercised the right of residence in Poland in accordance with the EU law before the conclusion of the transition period and they still live in Poland (the beneficiaries of the Withdrawal Agreement).
United Kingdom nationals arriving to Poland after the end of transition period, i.e. after 31st December 2020 will not be covered by the personal scope of Part II of the Withdrawal Agreement concerning citizens’ rights. They will not be considered as the beneficiaries of the Withdrawal Agreement. They will be covered by Polish legislation concerning third country (non-EU) nationals – the Act of 12 December 2013 on Foreigners (OJ of 2020 item 35).
In accordance with the Act of 12 December 2013 on Foreigners:
Permanent residence permit is granted to the foreigner who i. a. : remains in marriage to Polish citizen, recognized by the law of the Republic of Poland and remained in this marriage for at least 3 years before the date on which the application for granting permanent residence permit was submitted and immediately before submission of this application stayed on the territory of the Republic of Poland within the period not shorter than 2 years, on the basis of temporary residence permit granted in connection with being married to the Polish citizen or as a result of obtaining a refugee status, supplementing protection or permit for residence for humanitarian reasons.
Before applying for permanent residence permit in Poland you will have to obtain a temporary residence permit in Poland on the basis of a marriage to Polish citizen.
You will also be able to be covered by the future Polish legislation concerning third country family members of Polish citizens who return to Poland after having exercised their freedom of movement in another EU member state including the United Kingdom.