Embodiments disclosed herein are directed to integrated combustion assemblies including a perforated flame holder, combustion systems that include one or more integrated combustion assemblies, and related methods. For example, an integrated combustion assembly may be placed into service (e.g., integrated into a combustion system) as a complete and/or replaceable unit, such that elements and/or components of the combustion assembly are preassembled and no further assembly is required at the installation site.