What is the maximum speed limit on most interstate highways in Washington State?

The maximum speed limit on most interstate highways in Washington State is 70 mph. This speed limit is established to ensure safe and efficient traffic flow, allowing vehicles to maintain a pace that is suited for a major transportation route while balancing safety considerations.

The 70 mph limit also reflects the design of interstate highways, which are engineered for higher speeds with features such as multiple lanes, gentle turns, and reduced access points that contribute to a safer driving environment. It's important to note that certain areas, such as urban zones or sections with heavy traffic or construction, may have lower speed limits to accommodate increased vehicle density and safety concerns.