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Epitaxial VO2/TiO2thin film heterostructures were grown on (100) (m-cut) Al2O3substrates via pulsed laser deposition. We have demonstrated the ability to reduce the semiconductor–metal transition (SMT) temperature of VO2to ∼44 °C while retaining a 4 order of magnitude SMT using the TiO2buffer layer. A combination of electrical transport and X-ray diffraction reciprocal space mapping studies help examine the specific strain states of VO2/TiO2/Al2O3heterostructures as a function of TiO2film growth temperatures. Atomic force microscopy and transmission electron microscopy analyses show that the columnar microstructure present in TiO2buffer films is responsible for the partially strained VO2film behavior and subsequently favorable transport characteristics with a lower SMT temperature. Such findings are of crucial importance for both the technological implementation of the VO2system, where reduction of its SMT temperature is widely sought, as well as the broader complex oxide community, where greater understanding of the evolution of microstructure, strain, and functional properties is a high priority.