The Single European Sky Area comprises the States included in Performance Scheme of the Single European Sky.
- In RP1 (2012-2014): 27 EU Member States at the start of RP1 plus Norway and Switzerland (29 States in total).
- In RP2 (2015-2019): 28 EU Member States at the start of RP2 plus Norway and Switzerland (30 States in total).
- In RP3 (2020-2024): 27 EU Member States at the start of RP2 plus Norway and Switzerland (29 States in total).