Province : Ontario
Arms : Or a fess wavy Azure voided Argent above a base enarched paly Sable and Argent in dexter chief a lymphad Gules sails Argent and in sinister chief a garb Or fimbriated Azure.
Crest: A mural crown of three towers Argent masoned Azure charged with twelve Guernsey lily (Nerine sarniensis) proper six visible.
Motto: SARNIA SEMPER
The arms were officially granted on July 20, 1993.
The ship in the upper left hand corner depicts the historical significance of shipping to Sarnia as well as the current traffic and recreational boating for which Sarnia is well known. The golden sprig of broom is a component taken from the arms of the former Town of Clearwater and recognizes the rural area which remains an important part of the new city.
The blue line represents the St Clair River while the black and white tip in base, represents the railway line through Sarnia and the St Clair Railway Tunnel which joins Sarnia with Port Huron, Michigan.
The three tiered coronet represents civic government. It is charged with Guernsey Lilies (Nerine sarniensis) which is the national flower of the Isle of Guernsey from which the City of Sarnia derives its name. The national colours of red and white are represented in the flowers as well.
The motto means Always Sarnia.