The coat of arms was adopted in 2008, a year before Sermersooq became a subdivision of Greenland.

[1] The arms show an inuksuk (rock stack or cairn) in dark blue against a golden sun on a light blue field, standing on a white line representing an icesheet over stylized waves of blue and white.

The inuksuk is an historical way of marking the roads in Greenland.

[2] The ice sheet covers most of Greenland, and the waves are for the water beneath it.

[1] The arms are often depicted with a white background instead of a light blue one, as on the Sermersooq municipal website Archived 2018-03-10 at the Wayback Machine.