Madeira is a volcanic island whose economy is highly dependent on groundwater. Previous studies suggest that, besides precipitation, cloud water interception con- tributes to groundwater recharge. As such, the isotopic characterization of the sources of recharge is useful for the hydrogeological framework of the island. The δ18O and δ2H content of rain and cloud water was analyzed during three campaigns. Rain plots over a local meteoric water line (LMWL) whose equation is δ2H = 7.92 δ18O + 10.49 (R2 = 0.97, n = 43). The volume-weighted average meteoric line (WLMWL) is given by δ2H = 7.97 δ18O + 10.57 (R2 = 0.98, n = 20). Both are similar to the global meteoric water line which indicates, along with the d-excess values (10.8 and 11 ‰ for the LMWL and WLMWL, respectively), that rain originates, essentially in the Atlantic. Seasonal variations were also observed and rain in Campaign II was isotopically enriched and had a higher d-excess (δ18Omean -3.63 ‰; δ2Hmean -16.3 ‰; d-excess 12.7 ‰), than rain in Campaign III (δ18Omean -7.01 ‰; δ2Hmean -46.5 ‰; d-excess 9.5 ‰). Campaign I stood in between. These variations were probably the result of differences in temperature, water vapor source areas and rain forming processes. Rain was found to become increasingly depleted with altitude (δ18O), at a rate of -0.15 ‰/100 m and -0.11 ‰/100 m in the windward and leeward sides, respectively. Cloud water was always isotopically enriched when compared with rain at the same altitude. This was related to constant water vapor replen- ishment of orographic clouds, to the fact that it usually represents an early stage condensation from air moisture and to the smaller size of cloud water droplets when compared to rain droplets. These results will be useful to refine Madeira’s hydrogeological conceptual model. Future extended sampling during more years, with smaller sam- pling periods and single rainfall events should be useful to support the conclusions of this study.