In this paper, a miniaturized ultra-wide stop-band frequency selective surface (FSS) with angular stability and polarization insensitivity is presented. The FSS is composed of four symmetric square loops connected to each other using a small metallic strip. The proposed FSS shows good band rejection over the entire ultra-wideband (UWB), where <−10 dB and <−20 dB fractional bandwidths (FBW) are 143.71% (2.8–17.1 GHz) and 73.68% (6–13 GHz), respectively. The structure was made of a single side single layer FR4, which has one of the smallest size (0.074λ0 × 0.074λ0 × 0.014λ0) in this class of FSS. © 2021 Elsevier GmbH