| RCRand-Whitney Container LLC, Waterbury | Waterbury | CT | Paper Manufacturing322211 | 20-99 | ◐ LIKELY ACTIVE |
| RDRD Dynamics Corp | Bloomfield | CT | Transportation Equipment Manufacturing336413 | 100-499 | ◐ LIKELY ACTIVE |
| RDR Dee Winery | Enfield | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
REM Chemicals Inc. RU1 CT | Southington | CT | Fabricated Metal Product Manufacturing332813 | 1-19 | ◐ LIKELY ACTIVE |
| RGRestrictor Group | Westbrook | CT | Fabricated Metal Product Manufacturing332911 | 100-499 | ◐ LIKELY ACTIVE |
| RPRich Products New Britain | New Britain | CT | Food Manufacturing311520 | 100-499 | ◐ LIKELY ACTIVE |
| RERing's End Custom Millwork Division | Milford | CT | Furniture and Related Product Manufacturing337212 | 1-19 | ◐ LIKELY ACTIVE |
| RBRoller Bearing Company of America, INC. | Fairfield | CT | Fabricated Metal Product Manufacturing332991 | — | ◐ LIKELY ACTIVE |
| RBRoller Bearing CO of America, INC | Middlebury | CT | Fabricated Metal Product Manufacturing332999 | — | ◐ LIKELY ACTIVE |
| RRRoll Rite Torrington | Torrington | CT | Transportation Equipment Manufacturing336390 | 1-19 | ◐ LIKELY ACTIVE |
| RVRosedale Vineyards, LLC | Simsbury | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| RVRose Vineyards LLC | North Branford | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| RCR.S.A. Corp. | Danbury | CT | Chemical Manufacturing325199 | 20-99 | ◐ LIKELY ACTIVE |
| RCRtx Corporation | Middletown | CT | Transportation Equipment Manufacturing336412 | — | ◐ LIKELY ACTIVE |
| RBRyder - Birchstone Windsor Lock | Windsor Lock | CT | Wood Product Manufacturing321920 | 1-19 | ◐ LIKELY ACTIVE |
| SFSaltwater Farm Vineyard | Stonington | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
Sassone Labwear LLC | Norwalk | CT | Apparel Manufacturing315990 | — | ◐ LIKELY ACTIVE |
| SVSavino Vineyards | Woodbridge | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| SPSCA Pharma Windsor | Windsor | CT | Chemical Manufacturing325412 | 100-499 | ◐ LIKELY ACTIVE |
| SASchaeffler Aerospace USA - Winsted | Winsted | CT | Fabricated Metal Product Manufacturing332991 | 20-99 | ◐ LIKELY ACTIVE |
| SESchneider Electric EcoFit North Haven | North Haven | CT | Electrical Equipment, Appliance & Component Manufacturing335313 | 20-99 | ◐ LIKELY ACTIVE |
| SCSEK Corporation / Barr | Vernon Rockville | CT | Nonmetallic Mineral Product Manufacturing327390 | 1-19 | ◐ LIKELY ACTIVE |
| SCSentage Corporation | Rocky Hill | CT | Miscellaneous Manufacturing339116 | — | ◐ LIKELY ACTIVE |
| SNSerco - New London, CT | New London | CT | Transportation Equipment Manufacturing336611 | 20-99 | ◐ LIKELY ACTIVE |
| SSSetra Systems, INC. | Plainville | CT | Computer and Electronic Product Manufacturing334513 | — | ◐ LIKELY ACTIVE |
| SLShawn's LLC | Windsor | CT | Petroleum and Coal Products Manufacturing324122 | — | ◐ LIKELY ACTIVE |
Shepard Steel Co., Inc. - Miscellaneous Metals | Newington | CT | Fabricated Metal Product Manufacturing332323 | 20-99 | ◐ LIKELY ACTIVE |
| SMShow Motion, INC. | Milford | CT | Furniture and Related Product Manufacturing337110 | 20-99 | ◐ LIKELY ACTIVE |
| SASigns and Lines - Operations | Stamford | CT | Miscellaneous Manufacturing339950 | 1-19 | ◐ LIKELY ACTIVE |
| SASikorsky Aircraft CORP | North Haven | CT | Transportation Equipment Manufacturing336411 | — | ◐ LIKELY ACTIVE |
| SASikorsky Aircraft Corporation | Main Shelton | CT | Transportation Equipment Manufacturing336411 | — | ◐ LIKELY ACTIVE |
| SDSilgan Dispensing Systems Covit America Corporation, DBA Silgan Aluminum Solutions (Seemar) | Watertown | CT | Fabricated Metal Product Manufacturing332439 | 20-99 | ◐ LIKELY ACTIVE |
| SDSilgan Dispensing Systems Torrington | Torrington | CT | Plastics and Rubber Products Manufacturing326199 | 1-19 | ◐ LIKELY ACTIVE |
| SGSolenoid Group | Westbrook | CT | Fabricated Metal Product Manufacturing332911 | 100-499 | ◐ LIKELY ACTIVE |
| SPSolventum Purification Inc | Stafford Springs | CT | Machinery Manufacturing333999 | 100-499 | ◐ LIKELY ACTIVE |
| S1SoNo 1420 America's Maritime Distillery | Norwalk | CT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
Specialty Steel Treating - CT | East Granby | CT | Fabricated Metal Product Manufacturing332811 | 20-99 | ◐ LIKELY ACTIVE |
| SASpectrum Associates INC. | Milford | CT | Computer and Electronic Product Manufacturing334419 | — | ◐ LIKELY ACTIVE |
Springfield Spring Corporation - CT | Bristol | CT | Fabricated Metal Product Manufacturing332613 | 20-99 | ◐ LIKELY ACTIVE |
| SHSpring Hill Vineyards | New Preston | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| STSpringworks Therapeutics, INC. | Stamford | CT | Chemical Manufacturing325412 | — | ◐ LIKELY ACTIVE |
| SISpv Industries LLC | West Hartford | CT | Fabricated Metal Product Manufacturing332710 | — | ◐ LIKELY ACTIVE |
| SMSSI Mfg | Bristol | CT | Fabricated Metal Product Manufacturing332710 | 20-99 | ◐ LIKELY ACTIVE |
| SFStaehly Farm Winery | E. Haddam | CT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| SStamford | Stamford | CT | Chemical Manufacturing325611 | 1-19 | ◐ LIKELY ACTIVE |
| SSStatic Safe Products CO | Cornwall Bridge | CT | Fabricated Metal Product Manufacturing332999 | — | ◐ LIKELY ACTIVE |
| SMSterling Medical LLC | Milford | CT | Miscellaneous Manufacturing339112 | — | ◐ LIKELY ACTIVE |
| SEStewart EFI CT Warehouse | Thomaston | CT | Fabricated Metal Product Manufacturing332119 | 1-19 | ◐ LIKELY ACTIVE |
| SGStone Gardens Farm | Shelton | CT | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| SCStratford Connecticut | Stratford | CT | Computer and Electronic Product Manufacturing334513 | 100-499 | ◐ LIKELY ACTIVE |