The present research evaluates the physical properties and microstructure of no-cement mrtar specimens, which were developed using three waste materials, rice husk ash (RHA), ground granulated blast furnace slag (GGBFS), and circulating fluidized bed combustion fly ash (CFA), as binders. Various weight ratios of GGBFS/RHA were used (100/0, 15/85, 30/70, and 45/55), and CFA was added at ratios of 10, 15, and 20% of total binder weight. Slump flow and unit weight were used to evaluate the fresh properties of the no-cement mortar samples, while hardened properties of the mortar samples were evaluated through compressive strength (CS) and drying shrinkage tests. In addition, scanning electron microscopy/energy dispersive spectrometer and X-ray diffraction patterns were used to analyze the microstructure of the samples, while visual examination and loss CS tests were used to estimate sulfate resistance. As a result, the inclusion of RHA required a higher amount of superplasticizer in order to achieve a similar flowability with RHA-free mortar and remarkably reduced the fresh unit weight of the mortar mixture. In addition, the partial replacement of GGBFS with RHA up to 30% improved the 120-day CS of mortar specimens with 10, 15, and 20% CFA content by 8.8, 10.4, and 10.1%, respectively. Moreover, the developed no-cement mortars exhibited excellent performance against sulfate attack. Higher CFA content in the mixtures also generated higher volumes of hydration products and ettringite gel, which further increased mortar strength.