A water well can last anywhere from 25 to 100 years; however, there is no definitive answer to this question, as the lifespan of a well depends on several factors. Factors include the diameter and depth of the casing, the materials used in the well, the geological makeup of the surrounding soil and rocks, and how well the well has been maintained. Some wells may last for decades without needing any repairs or upgrades, while others may need to be replaced after only a few years. Ultimately, the best way to ensure your well lasts for as long as possible is to invest in regular maintenance and repairs. Additionally, if you live in a high water table area, you may need to replace your well more frequently than those who live in drier regions.