Alltru Credit Union is a member-owned, not-for-profit financial cooperative headquartered in Wentzville, Missouri, serving the St. Louis metropolitan area since 1968 (originally as McDonnell Douglas Credit Union, later 1st Financial Federal Credit Union until rebranding in 2020). The credit union operates multiple branches across St. Louis City, St. Louis County, and St. Charles County, with over 39,600 members and approximately $343.8 million in assets. Alltru is a federally insured institution and designated Community Development Financial Institution (CDFI).

Neighbors Credit Union is a federally chartered credit union serving the Saint Louis, Missouri area. The institution provides financial services to members within its defined field of membership. Limited public information is available regarding specific assets or membership size.

St. Louis Community Credit Union is a federally chartered credit union serving the Saint Louis, Missouri area. It provides financial services including savings accounts, loans, and other products to its membership. The institution operates as a member-owned cooperative financial institution regulated by the National Credit Union Administration.

Together Credit Union is a federally chartered credit union based in Saint Louis, Missouri. The institution serves members in the Saint Louis metropolitan area and surrounding regions. Together Credit Union offers standard credit union services including savings accounts, loans, and financial products to its membership base.

Vantage Credit Union is a federally chartered credit union located in Saint Charles, Missouri. It serves members in the St. Louis metropolitan area and surrounding regions. The institution provides standard credit union services including savings accounts, loans, and financial products to its membership base.