The Mw 5.3 Sulphur Peak earthquake in Idaho occurred on September 2, 2017. The epicenter was located in the east of Soda Springs in Idaho. The earthquake caused moderate shaking in southeastern Idaho, northern Utah, and western Wyoming. There were no reports of damage or death following the main shock. An active sequence of smaller aftershocks followed the main shock. This was very uncommon for an earthquake magnitude of this scale. The region is known to have moderate-to-high seismic hazard. Following the main shock, the United States Geological Surveying (USGS) had a scenario where it was likely that an earthquake of Mw 7.0 could happen in the region. The area’s seismicity and vulnerability of civil infrastructure in the nearby cities as well as potential for liquefaction, have not been studied in detail. This paper presents available data on seismicity of southeast Idaho. It uses ground motion records from the Sulphur Peak earthquake sequence to build the response spectra in accordance with ASCE 7-16. Preliminary findings from the response spectra and lessons learned from past earthquakes are discussed.