Projecting continued 58-percent asylum application approval rate so far this year and in 2015, the NGO said up to 968,000 people could be granted protection in the European Union based on applications received in 2015 and the first quarter of this year.
In 2016, 147,000 outstanding applications remain after decisions have been handed down in 199,000 out of 346,000 cases, MigrationWatch UK tallied.
It estimated that roughly 729,000 undecided applications remained from last year and 2014.
"Those granted refugee status in the EU have the legal right to citizenship as the Refugee Convention confers a responsibility on all signatories to facilitate access to naturalization," the NGO reminded.
"Once those granted refugee status are granted citizenship they will have full free movement rights across the EU and therefore the right to live and work in the UK, as will their family members."
In contrast to Britain, the European Union received over 1.25 third-country asylum applications in 2015, the same year that saw 1.85 million illegal border crossings into the bloc.
The think-tank estimated two weeks ago that migration from the European Union into the United Kingdom cost the British government up to $4.3 million per day based on benefits and public services.
