The conversion of carbon oxides (CO + CO2) to methanol is promising enough in concomitant decrease in greenhouse effect along with the mitigation of energy crisis. However, the process still confronts low levels of CO2 conversion and development of highly efficient catalyst is a bid challenge. In the present work, a syngas feed rich in CO2 was employed to produce methanol over a streak of La promoted Cu/ZnO/MgO catalysts where a harmonized synergy between the La and active Cu sites as a function of La content is reported. XRD analysis of Cu/ZnO/MgO/La2O3 precursors indicated the relative concentration of aurichalcite or malachite galleries. The optimized catalyst (2.5 mol% La) demonstrated the amplified population of malachite phase whereas suppression in aurichalcite phase. Presence of mixed phase precursor reflected well in Cu dispersion, small sized stable Cu particles and improved methanol synthesis activity with marginal deterioration in catalytic efficiency over 60 h on stream. A thorough investigation revealed that introducing La not only generated the required moderate basic sites but also enriched the catalytic surface with active Cu. XPS results indicated that La regulates interaction between Cu2+ and La3+ species, ultimately modifying the surface Cu/Zn ratio. CZ-M17.5La2.5 catalyst showed the highest carbon conversion with a methanol selectivity of 72.2% at 260 °C. This proves that La plays a crucial role towards methanol synthesis when blend of CO/CO2 is used as a feed.