A system, and computer program product for matching systems with power and thermal domains are provided in the illustrative embodiments. A subset of the set of systems is sorted according to size to form a sorted list of systems. The smallest remaining system in the sorted list of systems is selected. The smallest remaining system is allocated to a domain responsive to a determination that the domain can service the smallest remaining system. A system from a second subset is allocated to a plurality of domains such that the plurality of domains includes a smallest number of domains from the set of domains.