We demonstrated the feasibility of CaCuP thin film growth by reactive sputtering and evaluated its potential as a p-type transparent conductor. The electrical properties of CaCuP films generally confirm the theoretical expectations: CaCuP is a degenerate p-type semiconductor with a high hole mobility, even in non-epitaxial, polycrystalline films. The Cu-P hexagonal sheets throughout the crystal structure enable delocalisation of the hole generated by low energy copper vacancies, leading to large hole mobility in two directions. Ionised impurity scattering is predicted to be the dominant scattering mechanism at the carrier concentrations achieved experimentally in this study (1 × 10 20 cm -3 ), and the experimental temperature dependence of the mobility is qualitatively reproduced by the calculations. P content in the films was found to have a strong influence on crystal quality, which in turn determined the opto-electronic properties. Lower crystallinity is correlated with lower electrical conductivity, but also with higher absorption coefficients in the spectral region where indirect transitions dominate. Regardless of film composition, the absorption coefficient of CaCuP films was unexpectedly high. Hence, the maximum figure of merit of CaCuP as a trans-parent conductor was substantially lower than in the best n-type TCMs and somewhat lower than the highest values achieved by the state-of-the-art p-type TCM CuI.