Rainwater collecting is one of the most promising methods for augmenting limited surface and subsurface water resources in places where the current water delivery infrastructure is insufficient to satisfy demand. One of the measures for minimizing the effect of climate change on water supply is rainwater collecting. Rainwater collection is excellent in Abeokuta due to the city's average annual rainfall of 1,156 mm. The intra-annual range was 0.7 to 1.0, whereas the inter-annual variability was 0.2. Each home may collect 74.0 m3 of rainwater each year. Annual water consumption for flushing, washing, and flushing was estimated to be 21.6, 29.4, and 21.6 m3 correspondingly. Except in November, December, January, and February, harvested rainwater in Abeokuta can meet family monthly water needs for toilet flushing and washing. If there is enough storage, the extra rainfall saved in September and October will enough to replace the short fall in the dry months. The opportunity for water conservation is greatest between June and September, which are the two rainiest months in Southwest Nigeria.