This article presents a miniaturized antenna operating on ultra-wideband (UWB) spectrum having two reconfigurable notch bands. Initially, an antenna is designed for UWB applications, offering a 3.3–14.5 GHz impedance bandwidth. Subsequently, a semicircular stub and an arc-shaped slot are etched to achieve two distinguish notch bands at 3.7 and 8.1 GHz. PIN diodes are loaded onto the antenna to enable on-demand switching between notch bands. The final geometry of the antenna offers compact size of 15 mm × 20 mm × 1.6 mm and is designed using commercially available substrate material FR-4. The structure of antenna consists of a rectangular stub loaded into a circular patch, while an additional semicircular stub and arc-shaped slot are utilized to achieve notch bands. The antenna provides a moderate value of gain surpassing 2.5 dBi in the operational region. The antenna has the capability to operate between the UWB mode or the UWB mode having single or dual notch bands using two PIN diodes. To validate the simulated results, a hardware prototype of the design is fabricated and tested, yielding similar results obtained from software-based antenna. Finally, the antenna performance is compared with recently reported similar work in literature, demonstrating advantages such as miniaturization, wideband, moderate gain, and high efficiency along with on-demand switching characteristics while maintaining simple geometrical configuration. These characteristics highlight the scientific contribution of the proposed work along with making it a potential candidate for targeted applications.