Discovering trends and periodicities in the rainfall of a region provides essential information for understanding the climate especially the cyclic, periodic, persistent, or oscillatory patterns in rainfall. However, inadequate literature, lack of detailed research work, and data restriction to the 20th century necessitate the research. The research examines the trends and periodicities of rainfall over the Ibadan region from 1972 to 2020, Nigeria, using the Kendall tau correlation, the Spearman (rho) rank correlation, and the smoothed power spectral analysis. The results revealed upward trends in rainfall in all the stations, but only Idi‐Ayunre showed a significant trend (r = 0.034, 0.045) at p ≤ 0.05. Rainfall periodicities show that prominent short‐term periodicity of between 2.8 and 7.0 years and less prominent periodicity of 14.0 years were discovered in the rainfall series. The result provides a climatic shift toward increased rainfall and a wetter period. Thus, this study explains the trend and cyclic state of rainfall to water management for the Ibadan region and is important for agriculture and water resource planning.