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The Queen Elizabeth Islands, Canada, possess environments typical of the Arctic region. Polar deserts are the most extensive. The water budget of its basins is dominated by snowfall and snowmelt-generated runoff, giving rise to a nival regime of streamflow. Polar oases are warmer areas with enhanced evaporation and more variable flow than the deserts. Glaciers and late-lying snow cover provide late season high flows but experience low evaporation, though ice accumulation and melt constitute important storage changes. Wetlands have high flows similar to the polar desert, but evaporation reduces summer runoff, producing the distinctive wetland streamflow regime. Runoff ratios are high for polar deserts and glacierized basins, but the vegetated polar oases and wetlands exhibit ratios more comparable to the Low Arctic. A recent attempt to model a circumpolar water budget does not yield quantities that match field results, and further research is needed to refine the regional water balance.