Titania represents an important compound for property modifications in the widespread family of soda lime silicate glasses. In particular, such titania-containing glasses offer interesting optical and mechanical properties, for example, for substituting lead-bearing consumer glasses. Here, we provide a systematic study of the effect of TiO₂ on the structural, thermal, and mechanical properties for three series of quaternary Na₂O–CaO–TiO₂–SiO₂ glasses with TiO₂ concentrations up to 12 mol% and variable Na₂O, CaO, and SiO₂ contents. Structural analyses by Raman and magic-angle spinning ²⁹Si NMR spectroscopy reveal the presence of predominantly four-fold coordinated Ti^[4] atoms in glasses of low and moderate TiO₂ concentrations, where Si–O–Si bonds are replaced by Si–O–Ti^[4] bonds that form a network of interconnected TiO₄ and SiO₄ tetrahedra, with a majority of the non-bridging oxygen ions likely being located at the SiO₄ tetrahedra. At higher TiO₂ contents, TiO₅ polyhedra are also formed. Incorporation of TiO₂ strongly affects the titanosilicate network connectivity, especially when its addition is accompanied by a decrease of the CaO content. However, except for the thermal expansion coefficient, these silicate-network modifications seem to have no impact on the thermal and mechanical stability. Instead, the compositional dependence of the thermal and mechanical properties on the TiO₂ content stems from its effect on the network energy and packing efficiency.