| $350,000–1 million | SBC CONTRACTING INC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | SBM HOLDING LLC | SAINT LOUIS, MO | U.S. Bank, National Association |
| $1–2 million | SBS CREATIX, LLC | SAINT LOUIS, MO | Busey Bank |
| $2–5 million | SCHAEFER AUTOBODY CENTERS, INC. | SAINT LOUIS, MO | Carrollton Bank |
| $2–5 million | SCHAEFFER MANUFACTURING COMPANY | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | SCHAEFFER MARKETING GROUP INC | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | SCHAUB & SROTE LLC | SAINT LOUIS, MO | Central Bank of St. Louis |
| $350,000–1 million | SCHLICHTER, BOGARD & DENTON, LLP | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | SCHLUETER PERIODONTICS AND IMPLANTS | SAINT LOUIS, MO | PNC Bank, National Association |
| $350,000–1 million | SCHMERSAHL TRELOAR & CO., PC | SAINT LOUIS, MO | Busey Bank |
| $350,000–1 million | SCHMIDT RESTAURANT GROUP LLC | SAINT LOUIS, MO | Triad Bank |
| $1–2 million | SCHNEIDER ELECTRIC OF ST. LOUIS LLC | SAINT LOUIS, MO | The Central Trust Bank |
| $150,000–350,000 | SCHNEIDER INDUSTRIES INC. | SAINT LOUIS, MO | Regions Bank |
| $150,000–350,000 | SCHNELL EXPRESS LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $350,000–1 million | SCHOELLHORN-ALBRECHT MACHINE CO., INC. | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | SCHOEN & SCHMITZ, LLC | SAINT LOUIS, MO | First Community CU |
| $350,000–1 million | SCHOWALTER & JABOURI, PC | SAINT LOUIS, MO | Parkside Financial Bank & Trust |
| $350,000–1 million | SCHROEDER & TREMAYNE INC. | SAINT LOUIS, MO | CIBC Bank USA |
| $150,000–350,000 | SCHROEDER TRUCK REPAIR | SAINT LOUIS, MO | Bank of America, National Association |
| $150,000–350,000 | SCHUCHAT COOK & WERNER | SAINT LOUIS, MO | UMB Bank, National Association |
| $150,000–350,000 | SCI GROUP LLC | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | SCORCH AGENCY LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | SCOTSMAN COIN & JEWELRY, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | SCOTT BROTHERS INVESTMENT CORP | SAINT LOUIS, MO | Sterling Bank |
| $350,000–1 million | SCOTT LEE GUTTERING CO INC | SAINT LOUIS, MO | Commerce Bank |
| $1–2 million | SCOTT LEE HEATING COMPANY | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | SEAFOOD CITY INC | SAINT LOUIS, MO | Bank of America, National Association |
| $150,000–350,000 | SEAL TITE CORPORATION | SAINT LOUIS, MO | Midwest BankCentre |
| $350,000–1 million | SEALING SPECIALISTS, INC. | SAINT LOUIS, MO | Bloomsdale Bank |
| $1–2 million | SECOND STREET MEDIA, INC | SAINT LOUIS, MO | Midwest BankCentre |
| $350,000–1 million | SECOND STREET SANDWICHES, INC. | SAINT LOUIS, MO | Midwest Regional Bank |
| $2–5 million | SEILER INSTRUMENT MANUFACTURING CO INC. | SAINT LOUIS, MO | UMB Bank, National Association |
| $150,000–350,000 | SEILER PLASTICS CORPORATION | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | SELECT ORTHOPEDICS INC. | SAINT LOUIS, MO | St. Louis Bank |
| $2–5 million | SEMCO PLASTIC COMPANY | SAINT LOUIS, MO | Associated Bank, National Association |
| $150,000–350,000 | SEMMELMEYER - CORBY CO | SAINT LOUIS, MO | Busey Bank |
| $350,000–1 million | SENIORS HOME CARE LLC | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | SENSORY SOLUTIONS, LLC | SAINT LOUIS, MO | CNB Bank and Trust, National Association |
| $350,000–1 million | SENTRY SECURITY AGENCY OF ST. LOUIS INC. | SAINT LOUIS, MO | Regions Bank |
| $1–2 million | SERVICES BY DESIGN | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | SESSION FIXTURE CO., INC. | SAINT LOUIS, MO | Midwest BankCentre |
| $350,000–1 million | SFP LANDSCAPING INC | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $350,000–1 million | SFW PARTNERS, LLC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | SHA TIN, LLC | SAINT LOUIS, MO | Meramec Valley Bank |
| $350,000–1 million | SHAARE EMETH CONGREGATION | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | SHACK FRONTENAC | SAINT LOUIS, MO | American Bank of Missouri |
| $150,000–350,000 | SHANDS, ELBERT, GIANOULAKIS & GILJUM, LLP | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | SHANNAHAN CRANE & HOIST, INC. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | SHAPIRO METAL SUPPLY | SAINT LOUIS, MO | U.S. Bank, National Association |
| $2–5 million | SHAPIRO METALS COMPANY | SAINT LOUIS, MO | CIBC Bank USA |
| $350,000–1 million | SHERPA, LLC | SAINT LOUIS, MO | CIBC Bank USA |
| $150,000–350,000 | SHERWOOD FOREST CAMP INC. | SAINT LOUIS, MO | Midwest Regional Bank |
| $150,000–350,000 | SHOW ME INDUSTRIAL SERVICES INC | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | SHRINK TECH SYSTEMS, INC. | SAINT LOUIS, MO | UMB Bank, National Association |
| $150,000–350,000 | SHS HANLEY LODGING LLC | SAINT LOUIS, MO | Simmons Bank |
| $150,000–350,000 | SIBIC TRUCKING, LLC | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | SIDNEY INSULATION INC | SAINT LOUIS, MO | St. Louis Bank |
| $150,000–350,000 | SIDNEY STREET CAFE, LLC | SAINT LOUIS, MO | First Mid Bank & Trust, National Association |
| $150,000–350,000 | SIGNATURE CRAFT | SAINT LOUIS, MO | Bank Star |
| $150,000–350,000 | SILVER MAPLE PET CENTER, INC | SAINT LOUIS, MO | St. Louis Bank |
| $350,000–1 million | SILVERWEST-I CLAYTON HOLDINGS LLC | SAINT LOUIS, MO | Equity Bank |
| $150,000–350,000 | SIMON KATZ, INC | SAINT LOUIS, MO | Central Bank of St. Louis |
| $350,000–1 million | SIMPLY THICK, LLC | SAINT LOUIS, MO | Bank of America, National Association |
| $150,000–350,000 | SIMPTRONICS, LLC | SAINT LOUIS, MO | American Bank of Missouri |
| $2–5 million | SINCLAIR BUICK GMC TRUCK INC | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | SISTER SERVANTS OF THE HOLY GHOST OF PERPETUAL ADORATION | SAINT LOUIS, MO | UMB Bank, National Association |
| $350,000–1 million | SISTERS OF ST. JOSEPH OF CARONDELET, ST. LOUIS PROVINCE | SAINT LOUIS, MO | U.S. Bank, National Association |
| $350,000–1 million | SITEX ENVIRONMENTAL INC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | SKINNER & KENNEDY CO., INC. | SAINT LOUIS, MO | Cass Commercial Bank |
| $1–2 million | SLAH LLC | SAINT LOUIS, MO | Bank of Washington |
| $1–2 million | SLAM LLC | SAINT LOUIS, MO | Bank of Washington |
| $350,000–1 million | SLEEP DENTISTRY-ST LOUIS LLC | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | SLUHH,LLC | SAINT LOUIS, MO | WebBank |
| $150,000–350,000 | SMARTHOUSE HEATING & COOLING LLC | SAINT LOUIS, MO | Peoples National Bank, National Association |
| $350,000–1 million | SMG-II, LLC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | SMITH PATRICK PC | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | SMJM, LLC | SAINT LOUIS, MO | Busey Bank |
| $350,000–1 million | SO HOSPITALITY GROUP LLC | SAINT LOUIS, MO | Bank Star |
| $150,000–350,000 | SOAR MEDICAL, LLC | SAINT LOUIS, MO | UMB Bank, National Association |
| $1–2 million | SOCIETY OF ST. VINCENT DE PAUL ARCHDIOCESAN COUNCIL OF ST. LOUIS | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | SOCIETY OF THE SACRED HEART, UNITED STATES-CANADA PROVINCE, INC. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $350,000–1 million | SOLON GERSHMAN, INC. | SAINT LOUIS, MO | Central Bank of St. Louis |
| $350,000–1 million | SOLUTIONS AEC, LLC | SAINT LOUIS, MO | Carrollton Bank |
| $2–5 million | SOUND HEALTH SERVICES, PC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | SOUTH CITY CATHOLIC ACADAMY | SAINT LOUIS, MO | Peoples National Bank, National Association |
| $150,000–350,000 | SOUTH CITY COMMUNITY SCHOOL | SAINT LOUIS, MO | Cass Commercial Bank |
| $350,000–1 million | SOUTH COUNTY CHRISTIAN CENTER | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | SOUTH COUNTY PEDIATRIC ASSOCIATIES INC | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | SOUTH COUNTY UROLOGICAL,INC | SAINT LOUIS, MO | Newtek Small Business Finance, Inc. |
| $2–5 million | SOUTH SIDE MACHINE WORKS, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | SOUTH ST. LOUIS MEDICAL ASSOCIATES, LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $1–2 million | SOUTHLAND VOLKSWAGEN, INC | SAINT LOUIS, MO | St. Louis Bank |
| $350,000–1 million | SOUTHSIDE EARLY CHILDHOOD CENTER | SAINT LOUIS, MO | Commerce Bank |
| $1–2 million | SOUTHTOWN DODGE INC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | SOUTHWEST PEDIATRICS, INC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | SOUTHWESTERN ELECTRIC CO | SAINT LOUIS, MO | Regions Bank |
| $350,000–1 million | SOUTHWESTERN HEARING AID COMPANY INC | SAINT LOUIS, MO | Bank of America, National Association |
| $350,000–1 million | SOVEREIGN STL, INC. | SAINT LOUIS, MO | Bank of Prairie du Sac |
| $350,000–1 million | SOVEREIGN TECHNOLOGIES LLC | SAINT LOUIS, MO | Meramec Valley Bank |
| $150,000–350,000 | SPANISH SERVICE CENTER LLC | SAINT LOUIS, MO | Bank of America, National Association |