The present paper reports the successful detection of NO₂ using the hydrothermally synthesized SnO₂/RGO nanohybrids. The nanohybrids successfully detected NO₂ below its threshold limit value (TLV) with a minimum detection limit of 0.5 ppm. The 3-fold sensor response (R_g/R_a) was obtained towards 3 ppm of NO₂ at an operating temperature of 200 °C. Importantly, the nanohybrids exhibited faster response kinetics. For example, the response and the recovery times of 10 and 40 s, respectively were obtained for 1 ppm NO₂ exposure. In nanohybrids, the particle size of SnO₂ is ~5–7 nm which is comparable to twice of its Debye length (3 nm) and accordingly, benefits the charge transport and the sensor response. NO₂ adsorption on the sensor surface is further studied using the Elovich model. The obtained results were further corroborated with the observations from X-ray photoelectron spectroscopy (XPS) and Kelvin probe studies performed before and after exposure to NO₂. The considerable long-term stability and selectivity indicate that the developed sensor can find a promising application in NO₂ detection.