Antunes, C., 2011. Monitoring sea level change at Cascais tide gauge. Journal of Coastal Research, SI 64 (Proceedings of the 11th International Coastal Symposium), 870 - 874. Szczecin, Poland, ISSN 0749-0208 Sea level change (SLC) real-time monitoring has being developed and improved for the Portuguese tide gauge, based in FTP access to the internet server of the Portuguese geographical institute. A software application, named MareVB and in development since 2008, gets a 3 minute stream input of sea level height and a 10 minute stream input of air-pressure. Based on a predicted tide model, the sea level height is compared and analyzed, and storm-surge amplitude is determined, as well as the high frequency oscillation (seichas) due to the storm and tsunami waves. Using such real-time SLC data analysis, the application is now running as a coastal hazard warning system, emailing automatic warnings in real-time to national authorities and to other institutions and coworkers, where the levels of coastal hazards of SLC are considered. A post-processing monitoring of SLC is also performed and a time series is evaluated and actualized. Such SLC time series enables the statistics of storm-surges and the determination of the sea level rise rate associated to the global climate change and other regional phenomena. The computational methodology, the application for real-time monitoring and the statistics of storm-surges at Cascais for the period of last 10 years are presented here.