Because it is represented by relatively complete fossil material, Sebecus has been used to define larger groups of crocodyliforms such as Sebecidae and Sebecosuchia.
The suborder Sebecosuchia was established to group Sebecus with Baurusuchus and has grown to include many other sebecid and baurusuchid members.
While Sebecus and Baurusuchus are well known, other forms are known from only a few fragmentary specimens.

Sebecus has been placed in various positions among metasuchian crocodyliforms.
It has often been placed in a larger sebecosuchian clade.
Carvalho et al. (
2004) used Sebecus in their definition of Sebecidae, considering the clade to include the most recent common ancestor of Sebecus and Libycosuchus and all of its descendants.
Carvalho et al.
also established a sebecisuchian clade that was defined using Sebecus and referred to as Baurusuchoidea.
Sebecus and other sebecosuchians are often contrasted with the smaller-bodied Cretaceous notosuchians.
Turner and Calvo (2005) considered Sebecosuchia to be the sister taxon of Notosuchia and placed Sebecus as a basal member the clade.
Several recent phylogenetic analyses have resulted in a polyphyletic Sebecosuchia, with some members such as Baurusuchus being more closely related to notosuchians and other such as Sebecus forming a clade of metasuchians more distantly related to Notosuchia.
Larsson and Sues (2007) named this clade Sebecia.
The following cladogram simplified after an analysis of notosuchians presented by Pol et al.
in 2012.

*Note: Based on a specimen that was reassigned from Peirosaurus.
Because it is represented by relatively complete fossil material, Sebecus has been used to define larger groups of crocodyliforms such as Sebecidae and Sebecosuchia. The suborder Sebecosuchia was established to group Sebecus with Baurusuchus and has grown to include many other sebecid and baurusuchid members. While Sebecus and Baurusuchus are well known, other forms are known from only a few fragmentary specimens.
Sebecus has been placed in various positions among metasuchian crocodyliforms. It has often been placed in a larger sebecosuchian clade. Carvalho et al. (2004) used Sebecus in their definition of Sebecidae, considering the clade to include the most recent common ancestor of Sebecus and Libycosuchus and all of its descendants. Carvalho et al. also established a sebecisuchian clade that was defined using Sebecus and referred to as Baurusuchoidea. Sebecus and other sebecosuchians are often contrasted with the smaller-bodied Cretaceous notosuchians. Turner and Calvo (2005) considered Sebecosuchia to be the sister taxon of Notosuchia and placed Sebecus as a basal member the clade. Several recent phylogenetic analyses have resulted in a polyphyletic Sebecosuchia, with some members such as Baurusuchus being more closely related to notosuchians and other such as Sebecus forming a clade of metasuchians more distantly related to Notosuchia. Larsson and Sues (2007) named this clade Sebecia. The following cladogram simplified after an analysis of notosuchians presented by Pol et al. in 2012.
*Note: Based on a specimen that was reassigned from Peirosaurus.
Sebecus