Here are the titles for the last episodes of Supernatural. From Spoiler TV.
Supernatural - Episode 15.14 - Last Holiday
Supernatural - Episode 15.15 - Gimme Shelter
Supernatural - Episode 15.16 - Drag Me Away (From You)
Supernatural - Episode 15.17 - Unity
Supernatural - Episode 15.18 - Originally announced as Despair now said to be The Truth
Supernatural - Episode 15.19 - Inherit the Earth
Supernatural - Episode 15.20 - Carry On