Zillah is a city in Yakima County, Washington, United States, with a population of 3,179 as of the 2020 census.

Walter Granger, superintendent of the canal company, chose the town site in 1892.

She was the youngest member of an expedition to scout possible townsites; allegedly, the town was named for Zillah after she had fallen into a stream with the party's wagon and had to be consoled by her father.

[6] Granger housed the headquarters of the Washington Irrigation Company in Zillah, giving it economical advantages for a time.

He also made his residency in Zillah, becoming its mayor after retiring from the irrigation company.

[7] Zillah is located on Interstate 82 approximately 15 miles (24 km) southeast of Yakima.

According to the United States Census Bureau, the city has a total area of 1.78 square miles (4.61 km2), all of it land.

Its four schools are: Zillah is one of Yakima County's smallest districts by area, at an estimated 44 square miles.