Single-point incremental forming is a versatile process. It is being studied by many researchers and industries because of its ability to form various geometric shapes without the need for specific tooling. In the current research work, numerical and experimental investigation on thinning in parts formed using the incremental forming process is done. The influence of three-process parameters specifically pitch, tool diameter, and feed on thinning (minimum thickness) is investigated. A hemispherical-ended forming tool with an 8 mm tool diameter made of high-speed steel and aluminum blank Al-6061 with 0.8 mm thickness is used for experimental work. Results show that all the process parameters have a major influence on the minimum sheet thickness of formed surfaces. It is observed that small tool and high feed result in improved thickness, whereas the medium value of pitch results in less thinning.