Demand for cement increases sharply with urbanisation and industrialization. Limestone calcined clay cement (LC3) offers similar strength, better durability and is environmentally friendly compared to OPC. However, this ternary cement presents a few concerns, such as early setting time and higher water requirement, which leads to higher admixture dosage. To determine the effects of low clinker cement in concrete, this study analyses the effects of water content, w/c ratio and coarse aggregate to total aggregate ratio (c/a) on LC3 and OPC concrete mixes. The mixes were prepared using crushed sand as the fine aggregate and a modified polycarboxylate polymer-based superplasticizer. Then, SP dosage was optimised for each mix to achieve a maximum slump of 120 mm without bleeding and segregation. A reference mix was selected for comparative analysis based on workability and compressive strength results after 28 days at different water contents and c/a ratios. It was found that a stiff mix was produced at a low c/a ratio in the reference mix as the fines content and water demand increased. The details of the reference mix are a w/c ratio of 0.4, a c/a ratio of 0.66 and cement and water contents of 450 kg/m3 and 180 kg/m3, respectively. Finally, the mechanical properties of the mixes were evaluated after 7 days and 28 days for different w/c ratios of OPC and LC3 concrete. The work carried out in this study will be useful for the development of concrete mixes with LC3.