Embodiments herein relate to grill systems. In an embodiment, a grill system is included. The grill system having a grill assembly and a first side assembly. The grill assembly can include a grill cart and a burner box configured to couple to a top portion of the grill cart. The burner box can include a first connection structure. The first side assembly that can include a first side cart and a first top cap configured to couple to a top portion of the first side cart. The first top cap can include a second connection structure. The first connection structure and the second connection structure mate together to couple the grill assembly to the first side assembly. Other embodiments are also included herein.