The annual variability of runoff has not been analysed in the maritime Antarctic. Thus, we simulated and analysed rain, snow and glacier contributions to runoff related to climate variability in a small catchment over 11 years. The majority of the runoff came from snowmelt. Inter-annual variability in total runoff was associated with large variability in glacier runoff. Between October and May, 92 % of the runoff occurred, with significant runoff events outside the usual measurement season.