Different form factors of wearable technology provide unique opportunities for output based on how they are connected to the human body. In this work, we investigate the idea of delivering notifications through devices worn on the underside of a user’s clothing. A wearable worn in such a manner is in direct contact with the user’s skin. We leverage this proximity to test the performance of 10 on-skin sensations (Press, Poke, Pinch, Heat, Cool, Blow, Suck, Vibrate, Moisture and Brush) as methods of notification delivery. We developed prototypes for each stimulus and conducted a user study to evaluate them across 6 locations commonly covered by upper body clothing. Results indicate significant differences in reaction time, error rates and comfort which may influence the design of future under-clothing wearables.