Attack on Titan returns with the third season and, as announced during the ''Shingeki no Kyojin 'Reading & Live Event Orchestra' 'Attack Oto Taikan 2'', its premiere comes in July 2018. In addition, it was revealed that the anime will get a compilation film, which will be released on January 13, 2018. The film will be titled "Kakusei no Hōkō" (The Roar of Awakening) and will be a compilation film of the show's second season.

The staff revealed also a visual for the third season: 

The official website of the anime has confirmed that most of the second season's staff and cast are returning for the third season.

The second season of Attack on Titan premiered on April 1 and ended with 12 episodes, while the first 25-episode season was released in April 2014. The first season inspired two compilation films, Attack on Titan Part 1 - Guren no Yumiya and Attack on Titan Part 2 - Jiyuu no Tsubasa, which were released in November 2014 and June 2015, respectively. The second film added new ending footage that linked it to the second season.

Source: animenewsnetwork.com