In this work the instrumented indentation response of polycrystalline alumina and alumina-based ceramic multilayers with well known residual stresses have been investigated. Young's modulus and hardness were evaluated as a function of penetration depth with Berkovich and spherical indenters by continuous stiffness measurements. A size effect was observed due to the length scale of the microstructure. Values of hardness and Young's modulus obtained were in good agreement with previous works. No significant differences in the P-h curves were observed for materials with and without residual stress, making, then, difficult to employ the different methodologies derived for estimation of residual stress or crack length evaluation existing in the literature. Crack length had threfore to be measured by direct observation. In this respect, cube corner indentations did not produce well-developed radial cracks but chipping of the material, whereas indentations with Berkovich indenters produce radial cracks suitable for apparent fracture toughness estimation, and, consequently, residual stress.