As electronic cigarettes (e-cigarettes) have become more popular, research labs have begun to propose standardized vaping protocols to produce machine-generated aerosols from e-cigarette products. Investigations have largely focused on the effects of puff volume and duration on total particulate matter (TPM) deliveries, but little has been done to investigate the effects of the interpuff interval when testing these products. In this study, disposable, rechargeable, and tank systems were evaluated on a puff-by-puff basis using direct gas chromatography-mass spectrometry (GC-MS) analysis of each puff. A 55-mL puff volume and 3-second puff duration was used for each puff, which was captured in individual sample loops for direct GC-MS analysis. The relative abundance of nicotine was evaluated for each puff at increasing interpuff intervals (30 sec to 5 min) to determine the relative nicotine emissions, as well as to evaluate e-cigarette performance over the vaping session. The e-cigarette aerosol was also evaluated using traditional methods in which TPM is collected on a Cambridge filter pad, and nicotine extracted and measured using GC- flame ionization detection (FID). For all products tested, the largest nicotine delivery was observed in the first few puffs, with a rapid decrease as the number of puffs increased. When interpuff intervals were extended beyond 30 seconds, the relative nicotine delivery increased with increasing time interval until a plateau was observed after four minutes. These results suggest that the interpuff interval may significantly influence the delivery of nicotine for e-cigarette products. E-cigarettes may require a “recovery period” in order to produce more consistent puff-to-puff nicotine delivery during machine testing.