If there’s one rule of the road we learn long before driver’s ed, it’s this: Red means stop. Even a toddler can tell you the right shade of a stop sign. Since roughly the 1950s, all government-issued stop signs in the United States have been red. That’s why you might be surprised to see a blue stop sign. Blue stop signs aren’t issued by the Department of Transportation and are not permitted on public roads. They are, however, permitted on private properties like large estates, ranches, private golf courses, and country clubs. Essentially, if a property owner feels it’s necessary to warn drivers of any potential hazards that could require a stop, they install a blue stop sign at their own cost. Blue stop signs are a traffic feature primarily reserved for Hawaii. There's also some ambiguity as to whether blue stop signs can be enforced, but regardless of their legal status, if you encounter a blue stop sign in the U.S., it’s always best to stop and ensure the area is clear before proceeding.
