Self-reported experiences are often poor indicators of outward expressions. Here we examine social power as a variable that may impact the relationship between self-reported affect and facial expressions. Earlier studies addressing this issue were limited by focusing on a single facial expression (smiling) and by using different, less sensitive methods that yielded mostly null results. Sampling, for the first time, self-reported affect repeatedly in response to different negative, neutral and positive stimuli, and measuring concurrent facial muscle activation via electromyography, we found that high power (vs. baseline) increased the correspondence between self-reported positive affect and smiling. There was also an indication that high power (vs. baseline) bolstered the association between self-reported negative affect and frowning but the effect did not pass more stringent criteria for significance (p ≤.005) and was therefore deemed inconclusive. The prediction that low power (vs. baseline) decreases the correspondence between self-reported affect and smiling and frowning facial expressions was not supported. Taken together, it would appear that (high) power can impact the relationship between self-reported affect and facial expressions, but it remains to be seen whether this effect extends beyond smiling facial expressions.