Walla Walla is a city located in Walla Walla County, Washington. Walla Walla has a 2026 population of 33,901. It is also the county seat of Walla Walla County. Walla Walla is currently growing at a rate of 0.45% annually but its population has decreased by -1.09% since the most recent census, which recorded a population of 34,275 in 2020.