The distinction between underlying and excrescent stops in pairs like ‘mints’ and ‘mince’ was convincingly demonstrated by Fourakis and Port (1986). Several subsequent studies have been unable to replicate the result for speakers of American English, or have done so only partially. These studies have largely dealt with the acoustic signal. This study presents an approach to stop excrescence that refers to both the aerodynamics and articulation of the phenomenon. The results confirm and expand on the original findings. Using nasal flow as an indirect measure of velopharyngeal aperture and electropalatography (EPG) to estimate the moment of oral release, the presence of occlusion, as well as the duration of nasal and oral occlusion were measured. Overall contact across the palate was also measured. Disyllabic and monosyllabic tokens with /ns/ and /nts/ in final position were pronounced by four male speakers of American English. Disyllabic tokens could be either stressed or unstressed on the final syllable. In Experiment I, speakers produced tokens in a standard carrier phrase; in Experiment II, they produced one of the items in contrastive focus to its ‘homophonous’ counterpart, e.g., ‘I said mince not mints’. Underlying stops were significantly longer than excrescent stops, including in the contrastive-focus condition. A trading relation between nasal and oral stop duration was demonstrated when the stop was excrescent, but not when it was underlying. This suggests that the nasal–oral occlusion in epenethetic stops is divided proportionally between the underlying nasal and excrescent oral stop, but that the durations of the nasal and underlying oral stops are independent. ► Words like ‘mints’ and ‘mince’ may differ in the presence and length of t. ► Most studies of the pairs have dealt with the acoustic signal. ► This study uses articulation (EPG) and aerodynamics to measure the length of t. ► Underlying stops are shown to be longer than excrescent stops. ► For length of n and t, a trading relation is observed in excrescent stops.