| $150,000–350,000 | J. ZIMMERMAN LLC | SAINT LOUIS, MO | Regions Bank |
| $150,000–350,000 | J.P. COLLIER, INC. | SAINT LOUIS, MO | Bank Star |
| $5–10 million | J.S. LEASING COMPANY, INC. | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | J.S. WEINMANN, INC. DBA KENRICK'S MEATS & CATERING | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | JACKMAN'S INC | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $350,000–1 million | JAMES G STAAT TUCKPOINTING INC | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $150,000–350,000 | JAMES L. SCHMIDT, D.D.S., P.C. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $350,000–1 million | JAMES MULLIGAN PRINTING COMPANY | SAINT LOUIS, MO | FCB Banks |
| $150,000–350,000 | JAMES SURVEYING COMPANY | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | JANET MCAFEE INC. | SAINT LOUIS, MO | CIBC Bank USA |
| $150,000–350,000 | JANITRON MAINTENANCE MANAGEMENT SERVICES | SAINT LOUIS, MO | Royal Banks of Missouri |
| $150,000–350,000 | JAVELIN INC | SAINT LOUIS, MO | Midwest Regional Bank |
| $150,000–350,000 | JAY ELECTRIC CO LLC | SAINT LOUIS, MO | Midland States Bank |
| $1–2 million | JAY F. HAUSER, D.D.S., P.C. | SAINT LOUIS, MO | Bank of America, National Association |
| $150,000–350,000 | JAZZ ST LOUIS | SAINT LOUIS, MO | Busey Bank |
| $1–2 million | JB MARINE SERVICE, INC. | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $150,000–350,000 | JCV PRODUCTIONS INC. | SAINT LOUIS, MO | Midwest Regional Bank |
| $350,000–1 million | JEDMED INSTRUMENT COMPANY | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | JEMA, LLC | SAINT LOUIS, MO | First Bank |
| $350,000–1 million | JENKINS & KLING, P.C. | SAINT LOUIS, MO | 1st Advantage Bank |
| $150,000–350,000 | JEROME L. HOWE, INC. | SAINT LOUIS, MO | Triad Bank |
| $350,000–1 million | JERRY ACKERMAN MOTOR COMPANY, INC. | SAINT LOUIS, MO | St. Louis Bank |
| $2–5 million | JEWISH COMMUNITY CENTER | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $350,000–1 million | JEWISH FAMILY SERVICES OF ST LOUIS | SAINT LOUIS, MO | Busey Bank |
| $1–2 million | JEWISH FEDERATION OF ST. LOUIS | SAINT LOUIS, MO | Royal Banks of Missouri |
| $350,000–1 million | JH BERRA ENGINEERING & SURVEYING CO. INC | SAINT LOUIS, MO | Midwest BankCentre |
| $2–5 million | JH BERRA HOLDING CO INC | SAINT LOUIS, MO | Midwest BankCentre |
| $350,000–1 million | JH BERRA PAVING CO INC | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | JH HORSEMAN GROUP, LLC | SAINT LOUIS, MO | Peoples National Bank, National Association |
| $150,000–350,000 | JIM BUTLER ITALIA LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | JIM'S HEAVY HAULING, LLC | SAINT LOUIS, MO | Community First Bank of the Heartland |
| $150,000–350,000 | JJF & C, LLC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | JK PULLEY CO. INC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | JKC, INC | SAINT LOUIS, MO | Meramec Valley Bank |
| $150,000–350,000 | JL HOCHMAN COMPANY LLC | SAINT LOUIS, MO | Busey Bank |
| $350,000–1 million | JOCOR ENTERPRISES, INC. | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | JOE-K USED CARS | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | JOEY B'S 3 INC. | SAINT LOUIS, MO | Carrollton Bank |
| $1–2 million | JOHN BENDER INCORPORATED | SAINT LOUIS, MO | First Mid Bank & Trust, National Association |
| $350,000–1 million | JOHN D MCGURKS INC | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $2–5 million | JOHN HENRY FOSTER COMPANY OF ST LOUIS INC | SAINT LOUIS, MO | Busey Bank |
| $350,000–1 million | JOHN J. CONNELL | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $2–5 million | JOHN J. SMITH MASONRY COMPANY | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | JOHN S. WALLACH, P.C. | SAINT LOUIS, MO | BMO Harris Bank National Association |
| $150,000–350,000 | JOHN VAN DOREN, LLC | SAINT LOUIS, MO | First Bank |
| $2–5 million | JOHN VOLPI & COMPANY, INC | SAINT LOUIS, MO | Arvest Bank |
| $150,000–350,000 | JOHNNIE BROCK'S GREETING CARDS & GIFT SH | SAINT LOUIS, MO | Bank of Franklin County |
| $350,000–1 million | JOHNSON CLARKE, INC. | SAINT LOUIS, MO | Midwest BankCentre |
| $350,000–1 million | JOINT HEALTH, LLC | SAINT LOUIS, MO | First Bank |
| $350,000–1 million | JON ZURCHER | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | JONATHAN A SHANKER & BRIAN A SCHLUETER DMD MS PC | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $350,000–1 million | JOS WARD PAINTING CO | SAINT LOUIS, MO | Bank of America, National Association |
| $350,000–1 million | JOSEPH CAESAR INC | SAINT LOUIS, MO | Midwest BankCentre |
| $350,000–1 million | JOSEPH H. BEETZ PLUMBING COMPANY INC | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | JOSH NICHOLS ENTERPRISES, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | JOST BUILDERS, LLC | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | JPAM CONSULTING, INC | SAINT LOUIS, MO | Busey Bank |
| $350,000–1 million | JPAM MGMT & CONSULTING, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | JSB TAPAWINGO HOLDINGS LLC | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | JSC INC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | JTOH, INC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | JTW RESTOATION SERVICES, INC | SAINT LOUIS, MO | St. Louis Bank |
| $1–2 million | JUDEVINE, INC. | SAINT LOUIS, MO | First Bank |
| $150,000–350,000 | JUMBY BAY STUDIOS, LLC | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | JUNIPER RESTAURANT, LLC | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | JUNK DOCTORS LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | JURISTEMPS, INC. | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | JUST AROUND THE CORNER, INC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $350,000–1 million | JUSTINE PETERSEN HOUSING & REINVESTMENT CORPORATION | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | JW MECHANICAL LLC | SAINT LOUIS, MO | The Bank of Houston |
| $350,000–1 million | JW SOFTWARE, INC. | SAINT LOUIS, MO | Central Bank of St. Louis |
| $150,000–350,000 | JX. RESTAURANTS, INC | SAINT LOUIS, MO | U.S. Bank, National Association |
| $350,000–1 million | K & S ASSOCIATES, INC. | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | K. HALL STUDIO LLC | SAINT LOUIS, MO | Busey Bank |
| $2–5 million | KAEMMERLEN ELECTRIC CO. | SAINT LOUIS, MO | Cass Commercial Bank |
| $350,000–1 million | KAEMMERLEN PARTS & SERVICE INC | SAINT LOUIS, MO | Citizens Bank |
| $150,000–350,000 | KAF LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $350,000–1 million | KAI / ALLIANCE, LC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | KAI 360 CONSTRUCTION SERVICES LLC | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | KAI BUILD LLC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | KAI DESIGN & BUILD ENTERPRISES LLC | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | KAI ENGINEERING LLC | SAINT LOUIS, MO | Carrollton Bank |
| $1–2 million | KALDI'S, INC. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | KAMYKOWSKI GAVIN & SMITH PC | SAINT LOUIS, MO | PNC Bank, National Association |
| $350,000–1 million | KARPEL COMPUTER SYSTEMS INC | SAINT LOUIS, MO | Bank Star |
| $150,000–350,000 | KARR BICK CONSTRUCTION | SAINT LOUIS, MO | Montgomery Bank |
| $150,000–350,000 | KARR BICK KITCHEN & BATH | SAINT LOUIS, MO | Montgomery Bank |
| $350,000–1 million | KATIE'S PIZZA AND PASTA LLC | SAINT LOUIS, MO | Regions Bank |
| $150,000–350,000 | KAUFMAN BROADCAST SERVICES CORPORATION | SAINT LOUIS, MO | Carrollton Bank |
| $2–5 million | KCI CONSTRUCTION COMPANY | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | KDG REAL ESTATE, LLC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | KDM ENTERPRISES, LLC | SAINT LOUIS, MO | Peoples National Bank, National Association |
| $150,000–350,000 | KEEFE & GRIFFITHS, PC | SAINT LOUIS, MO | UMB Bank, National Association |
| $5–10 million | KELLY MITCHELL GROUP, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | KEMOLLS CHOP HOUSE | SAINT LOUIS, MO | Peoples National Bank, National Association |
| $350,000–1 million | KENNEDY PAINTING LLC | SAINT LOUIS, MO | Bank of America, National Association |
| $1–2 million | KENNELWOOD VILLAGE INC | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | KENNEY DESIGNER RESOURCES, INC. | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | KENRICK DESIGN/CONSTRUCTION SERVICES, INC | SAINT LOUIS, MO | Bank of Franklin County |
| $350,000–1 million | KENT PLUMBING, INC. | SAINT LOUIS, MO | Peoples Savings Bank of Rhineland |