MDMB-FUBINACA (aka MDMB(N)-Bz-F), chemical name Methyl (S)-2-(1-(4-fluorobenzyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate, a designer drug or a new psychoactive substance (NPS), was identified in three commercially available e-liquids formulated for electronic cigarette use. The e-liquids were evaluated using direct analysis in real time ion source attached to a time of flight mass spectrometer (DART-MS) and gas chromatograph mass spectrometer (GC–MS) to identify active ingredients/drugs, flavorants, and other possible constituents. The e-liquids were also evaluated for alcohol content by headspace gas chromatography with flame ionization detector (HS-GC–FID). The aerosol produced from the e-liquids by use of an e-cigarette was analyzed by solid phase micro-extraction gas chromatography mass spectrometry (SPME–GC–MS) to ensure delivery of the active ingredient/drug. Propylene glycol, vegetable glycerin, MDMB-FUBINACA, alcohol content and a flavor profile were determined for each of the e-liquids. MDMB-FUBINACA was determined to be the major active ingredient in all three e-liquids and was successfully detected by SPME–GC–MS in the aerosol generated by a KangerTech Aerotank clearomizer/electronic cigarette.