Index

Index (Lushootseed: x̌əx̌aʔusalʔtxʷ) is a town in Snohomish County, Washington, United States. The population was 155 at the 2020 census, making it the smallest municipality in the county. Index lies at an elevation of 541 feet (165 m) along the North Fork Skykomish River in the Cascade Mountains. It is connected to surrounding communities by U.S. Route 2.

The town was established in 1889 by Amos Gunn and his family after they purchased an existing claim to build a home and hotel. It was named for Mount Index (now Baring Mountain), which resembled an index finger. Index became a stop on the Great Northern Railway in 1893 and was platted the same year amid a boom in mineral exploration in the area. The town reached its peak population of 1,000 residents by 1900 and was incorporated as a municipality on October 11, 1907.