NEM relay is a promising class of device to overcome the power crisis of CMOS circuits. To design these devices and predict their scaling properties, an analytical model highlighting the fundamental physics of the relay operation is highly desired. This work presents a new 2D analytical model for the study of NEM relay scaling. The model retains the physical insights for NEM relays and yet has the simplicity close to the commonly used 1D model. The error as compared to a finite element model is reduced from ∼25% (1D model) to ∼3% (this work) by introducing a ratio R(a) to account for 2D effects in the 1D formulation. Besides the fundamental mechanical and electrical properties, the model also takes into account surface forces in the operation of NEM relay devices. The impact of surface forces on the operation voltage as devices are scaled down is discussed.