Nowadays, there are many methods to predict thefuture value of several things. In this paper, the Holt-Winters Ex-ponential Smoothings applied to forecast the tidal level in Cilacap.Then the Holt-Winters forecasting performance compared withthe ARIMA (Autoregressive Integrated Moving Average), andSARIMA (Seasonal-Autoregressive Integrated Moving Average),in order to see which one that can produce the best forecast. Themethod performance measured by using root mean square error(RMSE) and R-Square. The Holt-Winters Exponential smoothingproduces RMSE and R-Square that are better than ARIMA andSARIMA. The choice of seasonal period significantly affects theforecasting result produced by the Holt-Winters method.