Transition metals exemplify correlated electronic systems, where electron-electron (e−e) scattering often results in a quadratic temperature dependence of the electrical resistivity, p(𝑇) ∝T². In SrVO₃ (SVO), a material with a V−3d¹⁢ electronic configuration that ensures metallicity through narrow 3d-t_2g bands, a p(𝑇) ∝T² dependence has been reported. While traditionally attributed to e−e scattering, recent studies suggest that electron-phonon (e-ph) interactions may play a significant role. To unravel the influence of phonon interactions on carrier transport in SVO, we present a comparative study of the transport and optical properties of SVO films with partial substitution of ¹⁶O ions by their heavier isotope, ¹⁸O. Our findings reveal that ¹⁸O substitution induces a change in the slope of dp(T)/dT at nominal fixed carrier density, highlighting the dominant contribution of e-ph coupling over e−e scattering in determining p(T). Furthermore, it is found that the ¹⁸O substitution softens the phonon lattice and promotes a reduction in plasma frequency and an increase in the carrier effective mass. These results indicate that the e-ph coupling strength increases upon ¹⁸O  substitution. Our findings suggest that e-ph interactions may surpass e−e scattering in governing the resistivity of metallic ionic lattices.