Shield: From the Provincial Seal of La Union where the Municipality is located.

1886: Year when Tubao was founded.

Scroll: Provincial motto in local dialect --"In Unity There Is Strength"

Upper Design: Boiling cauldron, shaking hand, and native tobacco: Warmth, unity, peace and reconciliation. An ever-burning desire in preserving oneness.

Central Design: Angel who helped St. Isidore, the patron saint of farmers.

Lower Design: Major crop of the town.