In this pre-registered study, we investigated whether emotional inner speech influences heart rate. Participants were asked to engage in 3-minute sessions of: positive inner speech, negative inner speech, or inner counting while their heart rate was monitored. Participants were lying on a bed and asked to remain still. Motion tracking was applied to control for body movement. Median heart rate across each inner speech session was analyzed and a significant difference was found between emotional inner speech and inner counting. No difference between positive and negative inner speech was observed. Post-hoc analyses investigated the relationship between movement and heart rate and found an effect with a peak lag of approximately 14 seconds. Removing these effects did not change the effect of emotional inner speech. Additional analyses showed that heart rate and respiration rate were linked. Including respiration rate as a covariate did not alter the effect of emotion.