A wealth of evidence indicates the existence of a consolidationphase, triggered by and following a practice session, wherein newmemory traces relevant to task performance are transformed andhoned to represent new knowledge. But, the role of consolidation isnot well-understood in category learning and has not been studied atall under incidental category learning conditions. Here, weexamined the acquisition, consolidation and retention phases in avisuomotor task wherein auditory category information wasavailable, but not required, to guide detection of an above-thresholdvisual target across one of four spatial locations. We compared twotraining conditions: (1) Constant, whereby repeated instances of oneexemplar from an auditory category preceded a visual target,predicting its upcoming location; (2) Variable, whereby five distinctcategory exemplars predicted the visual target. Visual detectionspeed and accuracy, as well as the performance cost of randomizingthe association of auditory category to visual target location, wereassessed during online performance, again after a 24-hour delay toassess the expression of delayed gains, and after 10 days to assessretention. Results revealed delayed gains associated with incidentalauditory category learning and retention effects for both trainingconditions. Offline processes can be triggered even for incidentalauditory input and lead to category learning; variability of input canenhance the generation of incidental auditory category learning.