This study aims to determine mechanical and thermal properties of Saint-Maximin limestone, similar to the Lutetian stone found in the vaults of the Notre-Dame de Paris cathedral, and their variations after heating–cooling cycles at temperatures up to 800 °C. An extensive experimental campaign, including both destructive and non-destructive testing, was carried out. The results indicate that the samples can be considered to be isotropic, and the effect of temperature on Poisson's ratio, static modulus of elasticity, compressive and tensile strengths were measured. Non-destructive testing revealed that the usual correlation equations between ultrasonic measurements and mechanical properties are not valid for heated stone samples, particularly when estimating Poisson's ratio. An alternative measurement method using impulse modal analysis was proposed to overcome this issue. Uniaxial compressive tests on specimens of different geometries were used for the estimation of shape factors specific to Saint-Maximin stone. Some of these shape factors contradict the current European standard for stone, which seems to overestimate the effect of slenderness. The study also suggests shape factors after heating at 300 °C and 600 °C to account for the effect of heating on the compressive strength. The results demonstrate that, while the correlations established for stones at room temperature remain valid, they are not necessarily accurate after a heating–cooling cycle. This study provides important information for the numerical modelling of this material from mechanical and thermal perspectives.