The cost of building a pool can depend on various factors, such as the size, depth, materials used, site preparation, and additional features. However, in general, a rectangular or square-shaped pool is usually the cheapest shape to build.Rectangular and square-shaped pools are straightforward in terms of design and require less labor and materials than custom or irregular-shaped pools. They also allow for easier installation of pool covers, automatic cleaners, and safety features such as fencing.Circular pools are also a popular and relatively affordable option, but they can be less efficient in terms of space utilization and may require more water to fill than a rectangular or square pool.It’s important to keep in mind that the overall cost of a pool can vary greatly depending on the specific design and materials used, as well as other factors such as site preparation and pool equipment. Consulting with a professional pool builder and getting multiple quotes can help you determine the most cost-effective pool design for your specific needs and budget.