Great Western Bank (previously known as Great Western Savings & Loan) was a large consumer bank that operated primarily in the Western United States. Great Western's headquarters were in Chatsworth, California. The bank was acquired by Washington Mutual in 1997 for $6.8 billion.

Great Western Bank was held by Great Western Financial Corporation ("GWFC"), a corporation organized under the laws of the state of Delaware.

The Forum, an arena in Inglewood, California, famous as the former home of the Los Angeles Lakers and Los Angeles Kings, was known as the "Great Western Forum" for several years. This name came from Great Western S&L, which paid for the naming rights on the arena in 1988. The name still remained for several years though Great Western ceased to exist. The 15-year naming rights contract expired in 2003, and the Great Western name was finally removed in 2006.

Over ten years after the takeover, Great Western's logo is still visible in several places at their former headquarters in Northridge.