This work presents an in-depth wide-frequency band assessment of 28 nm FDSOI MOSFETs for analogue and RF applications.The focus is mainly on such figures of merit (FoM) as the transconductance g(m), the output conductance g(d), the intrinsic gain A(v), and the cut-off frequencies f(T) and f(max). Firstly, 28 nm FDSOI MOSFETs are compared with other advanced devices and are shown to outperform them. Secondly, g(m)-A(v), analogue metric is demonstrated to be affected by operation frequency. Small-signal parameters variation is limited and dominated by self-heating effect. This is in contrast to the first generation of ultra-thin body and BOX devices without a ground plane where coupling through the substrate has a considerable effect. Thirdly, the self-heating effect is analysed and shown to be smaller than previously predicted by simulations for such devices. Fourthly, it is shown that f(T) of similar to 280 GHz and f(max) of similar to 250 GHz are reachable in the shortest devices. These values are compared to those of the first generation of UTBB devices through the effect of parasitic elements. (C) 2015 Elsevier Ltd. All rights reserved.