There will be eight groups of six teams and a ninth group of five teams with 23 sides to join hosts France in the final tournament.
The seedings, decided by UEFA's coefficient system which is different to FIFA's world ranking, will see the Republic of Ireland among the pot of second seeds, Scotland and Wales in the pot of the fourth seeds, and Northern Ireland in the pot of fifth seeds.
The draw will take place in Nice on February 23.
UEFA also announced that the hosts France will play friendly matches against the countries in the five-team ninth group - but these games will not count towards qualifying points.
Organisers are also considering a radical proposal for electronic tickets to be used at the Euro 2016 finals rather than the traditional paper tickets.
Euro 2016 president Jacques Lambert: "We are looking whether to have e-tickets or paper tickets.
"This is a decision that cannot be taken without in-depth study and looking at issues of security. There is still a lot of work to do before the decision is taken."
Lambert said the teams in the finals would have group matches spread all over France rather than based around a single city.
He added: "The idea is to have them rotate among different stadia and this system was very much appreciated in the 1998 World Cup because it allowed foreign fans the possibility to enjoy this event with a tourist aspect to it as well as football, and it allowed for people in France to see all the different teams."
Meanwhile, UEFA president Michel Platini refused to be drawn on fellow Frenchman Jerome Champagne's declaration this week that he will run for FIFA president.
Platini insisted he will not decide himself whether to run before the World Cup and said about Champagne's announcement: "In all honesty I didn't see it or read a great deal about it and all I can say is 'best of luck'.
"I wish the best of luck for all those who will run for FIFA."
The draw will see, for political reasons, Azerbaijan kept apart from Armenia and Spain in a different group from Gibraltar.
There had initially been concerns over Russia and Georgia but both associations have stated they are happy to play against each other.