Continuous technology advancements have forced MOSFET architecture to evolve from bulk to SOI to multigate MOSFETs. BSIM compact models have helped circuit designers to realize their designs first time correct using accurate physical models used in SPICE simulation. BSIM3 and BSIM4 are threshold voltage based bulk MOSFET models while BSIM6 is charge based bulk MOSFET model, which include physical effects such as mobility degradation, current saturation, high frequency models etc. BSIM6 has been developed especially to address symmetry around Vds = 0, thus providing smooth higher order derivatives. BSIM-CMG is a CMC standard surface potential based model for common symmetric double, triple, quadruple and surround gate (nanowire) MOSFETs. Long channel DIBL also called Drain-Induced Threshold Shift (DITS) effect and asymmetric charge weighing factor etc. have been recently included in it. BSIM-IMG is a surface potential based model to simulate ultra-thin body devices such as UTBSOI but also other thin body devices such as MOS2 transistor.