Proprioceptive information makes us able to perceive the position of our joints from an internal point of view. In the certain cases, proprioceptive information has to be stored in short-term memory, for example, during the learning of new motor skills or the assessment of proprioceptive accuracy. However, there are contradictory findings about the modality-specific storage of proprioceptive information in working memory. In this preregistered study, we applied the interference paradigm, assessing proprioceptive memory capacity in the subdominant elbow joint for 35 young individuals in five different experimental conditions: (a) without competing task/interference (baseline condition), (b) with motor interference, (c) with spatial interference, (d) with visual interference, and (e) with verbal interference. Proprioceptive span was lower in the verbal and spatial interference condition than in the baseline condition, whereas no significant differences were found for the motor and visual conditions. These results indicate that individuals use verbal and spatial strategies to encode proprioceptive information in short-term memory, and, in contrast to our expectation, the motor subsystem of working memory is not substantially involved in this process.