This paper presents a comprehensive multicriteria performance index analysis to find the most suitable screed composite to be used in flooring applications. The mechanical and durability properties and the economic and environmental impact of various screed mixes were considered. The screed composites were prepared by varying the mix design parameters, including the binder (cementitious and geopolymeric), fine aggregates (crushed sand or dune sand), solution-to-binder ratio, and binder-to-aggregate ratio. Compared to cementitious mixes, geopolymer screeds demonstrated higher production costs but remained competitive in terms of cost per unit strength and durability–cost relationship. Geopolymer screeds also exhibited lower global warming potential values, highlighting their environmental advantage over cementitious counterparts. Upon synergic consideration of the examined response criteria, the multicriteria performance index analysis showed that geopolymer screeds produced with crushed sand demonstrated superior performance among the different screed mixes for category A types of screeds. At the same time, cement-based mix produced with crushed limestone performed the best as a category B type of screed. However, the geopolymer screed produced with a binder-to-crushed sand ratio of 1:7 was superior to all category B screed mixes when cost and environmental impact were considered solely.