The flag of the state of Washington consists of the state seal (which bears an image of George Washington) on a field of dark green with gold fringe being optional. It is the only U.S. state flag with a field of green as well as the only state flag with the image of an American president. Because the seal must be stitched on both sides, the flag is the most costly state flag in the United States.
WA flag proposal "Bulgaria" by Dean Thomas. Tricolor colors represent snow, flora, and ocean. The full arms of George Washington sits in the white stripe at extreme left.
WA flag proposal #2 by Dean Thomas. Blue stripe for Pacific Ocean, Green stripe for the state flora, White stripe for the snowy peaks. The Shield from George Washington's COA are in the center of the flag.
My version of "Hoofer 7." The flag is broadly an abstraction of the original flag adopted in 1923 containing the state seal. The new center icon is blue for the Pacific Ocean and Puget Sound, gold for the fertile soil and valleys of eastern Washington, and white for the snow-capped Cascade Mountains. The star has eight points like a ship’s compass, alluding to the state’s maritime history. The white star on the blue round also looks like a topographic map of Mt. Rainier. The green field nods to the state’s nickname “The Evergreen State.” Posted by Preston Knapp 
WA Flag Proposal "apollohawkridge 1"
WA Flag Proposal "apollohawkridge 2"
WA Flag Proposal "apollohawkridge 3"
Proposal "Rainier" for a flag for the state of Washington, showing Washington's head in yellow and mount rainier in white on a green background. By Qaz Dec 2019 (details)
Washington State flag redesign by Luismanuel1995. November 2019
Green represents the state's lush forests. Blue represents the waters of the puget sound and columbia river. White represents the eternal blanket of clouds that cover the state. The orca is a popular symbol for the native tribes and is a native mammal to the area
flag by rr2701
Current Seal, Pacific NW Colors, and Salish Thunder Bird
A large number of proposed flags of Washington use or allude to George Washington's coat of arms as an alternative way to commemorate the state's namesake. Since the District of Columbia already uses a banner of Washington's arms as its official flag, most designs make changes to it, often in a way that adds additional symbolism.
Eastern Washington is a unique region within Washington. Separated from the rest of the state by the Cascade Range, the climate is generally much drier, and the population is much smaller and more spread out. Reflecting this uniqueness, a separate regional flag (such as the one below) may serve as an informal source of pride.