Siats (/see-ats/) is an extinct genus of large theropod dinosaurs known from the Late Cretaceous Cedar Mountain Formation (Mussentuchit Member) of Utah, United States.

It was collected between 2008 and 2010 from the Mussentuchit Member of the Cedar Mountain Formation in Emery County of Utah, dating to the early Cenomanian stage of the Late Cretaceous, approximately 94.5 million years ago.

[1][2][3] The Siats holotype specimen consists of material from a single individual that is considered skeletally immature based on the incomplete fusion of neural arches to the centra of the dorsal vertebrae.

[6] Naish and Cau (2022) recovered the taxon as the basalmost megaraptoran, with this clade diverging after Xiongguanlong, and supported Siats and Chilantaisaurus as representing a wave of gigantism in tyrannosauroids preceding the Tyrannosauridae.

[7] In their 2025 analysis of allosauroid phylogenetics, Kellermann, Cuesta & Rauhut consistently recovered Siats as a megaraptoran, noting that it shares a specific position of pneumatic fossa with this clade.