Smart Financial Credit Union is a federally chartered credit union based in Houston, Texas, serving members across the state. The institution provides a full range of financial services including savings accounts, loans, and investment products to its membership base.

Soarion Credit Union (formerly Air Force Federal Credit Union) is a San Antonio-based federal credit union founded in 1952 by airmen at Lackland Air Force Base. It serves approximately 55,000 members across San Antonio, Del Rio, Texas, and Columbus, Mississippi, with a heritage rooted in military service but open to the general public. The credit union offers checking, savings, auto loans, mortgages, credit cards, and other financial products.

Solarity Credit Union is a federally chartered credit union headquartered in Yakima, Washington, serving members across Washington state and beyond. The institution provides comprehensive financial services including savings, lending, and investment products to its membership base.

Sound Credit Union is a federally chartered credit union based in Tacoma, Washington, serving members in the Puget Sound region. The institution provides traditional banking services including savings accounts, loans, and financial products to its membership base.

South Carolina FCU is a federally chartered credit union headquartered in North Charleston, South Carolina. The institution serves members across South Carolina and surrounding regions. It offers standard credit union services including savings accounts, loans, and financial products to its membership base.

Southern Energy Credit Union, headquartered in Birmingham, Alabama, is the second-largest credit union in Alabama and the largest state-chartered credit union in the state. Founded in 1953 as APCO Employees Credit Union, it rebranded in 2025 following mergers with Powerco Federal Credit Union and Mutual Savings Credit Union. The institution serves over 90,000 members through 28 branches across Alabama, Georgia, and Mississippi, with over $3.5 billion in assets.

Southland Credit Union is a federally chartered credit union headquartered in Los Alamitos, California, serving members in Southern California. The institution provides traditional credit union services including savings accounts, loans, and financial products to its membership base.

Southwest Airlines Federal Credit Union is a credit union based in Dallas, Texas, primarily serving employees and members affiliated with Southwest Airlines. It is a federally chartered institution that provides financial services to its membership base. The credit union operates as a member-owned cooperative financial institution.

Sovita Credit Union is a federally chartered credit union serving the Flint, Michigan area. The institution provides financial services to its membership base in the region. Limited publicly available information is available about this credit union.

Space Coast Credit Union is a federally chartered credit union headquartered in Melbourne, Florida, serving the Space Coast region. The institution provides financial services including savings accounts, loans, and other member products to eligible individuals in Brevard County and surrounding areas.