We report on a measurement made of cosmic ray electrons and positrons between 20-300 MeV with the balloon-borne spectrometer AESOP-Lite, which was flown from Esrange, Sweden to Ellesmere Island, Canada in May 2018, at an average altitude of ∼3 g cm−2 of residual atmosphere. The maiden AESOP-Lite flight took place in May 2018, accumulating roughly 130 hours of exposure above 130,000 feet. This paper gives an overview of AESOP-Lite’s science goals, instrumentation and the 2018 balloon campaign. We describe the selection criteria for particle identification, the methodology of the analysis, and very preliminary results of the electron spectrum in the energy regime of 20 to 300 MeV obtained on this flight.