| # | Company | Employees |
|---|---|---|
| 1 | 47,247 | |
| 2 | 38,917 | |
| 3 |
GXO Logistics, Inc.gxo.com
Providing innovative opportunities in logistics through advanced automation, benefiting customers, employees, and investors alike |
36,174 |
| 4 |
Cigna Healthcarecigna.com
Benefits provider, guides customers through healthcare system, empowering them with information and insight to improve health and vitality. |
29,662 |
| 5 |
Stanley Black & Decker, Inc.stanleyblackanddecker.com
Provider of tools, fasteners, and infrastructure systems supporting home repair, automotive security, construction, and energy industries with innovation and safety. |
29,460 |
| 6 |
Gartnergartner.com
A global company providing expert-led research and data-driven insights to help executives make faster, smarter decisions and achieve stronger performance |
22,206 |
| 7 |
The Hartfordthehartford.com
The company goes beyond providing insurance to protect individuals and businesses, making an impact through human achievement and comprehensive protection |
21,627 |
| 8 |
Synchronysynchrony.com
provides consumer financing solutions enabling millions to access essential needs and connects them with small businesses and health providers |
16,106 |
| 9 | 9,330 | |
| 10 |
Eversource Energyeversource.com
A Fortune 500 energy company in New England, prioritizing safety, reliability, environmental leadership, and energy options for millions of customers |
8,353 |
| 11 |
Terex Corporationterex.com
A global manufacturing company focused on building essential machines, improving lives, volunteering, and maintaining a safe, inclusive work environment |
8,109 |
| 12 |
Hubbell Incorporatedhubbell.com
Manufacturer of utility and electrical solutions focused on grid modernization, clean energy, electrification, and energy efficiency worldwide. |
7,655 |
| 13 |
Praxair, Inc - a Linde Companylindeus.com
A global leader in industrial gases and engineering, providing high-quality gases, technologies, and services to diverse markets while promoting sustainability and productivity |
6,549 |
| 14 |
Amphenolamphenol.com
A Fortune 500 manufacturer with 90,000 employees worldwide, providing key components for electronic devices and networks in daily use |
5,559 |
| 15 |
Crane Companycraneco.com
Long-standing ethical business focused on innovation, disciplined management, strategic acquisitions, and creating value for customers, suppliers, and shareholders. |
4,696 |
| 16 |
IMS Healthiqvia.com
Provides healthcare data, analytics, and technology solutions to improve clinical, commercial, and real-world outcomes in the life sciences industry. |
4,675 |
| 17 |
Electronic Data Systemsdxc.com
A global company founded in 1962 offering electronic data processing management personnel and computer hardware, focusing on large corporations and government contracts |
3,809 |
| 18 |
Interactive Brokersinteractivebrokers.com
Provides automated trade execution and custody for diverse financial instruments across global markets, offering advanced tools and research at low cost. |
3,506 |
| 19 |
Hexcel Corporationhexcel.com
Production of carbon fiber reinforcements, resin systems, and honeycomb materials focused on lightweight solutions for commercial aerospace industry. |
3,357 |
| 20 |
EMCOR Group, Inc.emcorgroup.com
Leading in mechanical and electrical construction, EMCOR Group specializes in planning, installing, and maintaining sophisticated facility systems for various sectors with a skilled workforce |
3,333 |
| 21 |
Ethan Allen Global, Inc.ethanallen.com
Innovative furniture retailer with a wide range of styles, offering customization options and environmentally sustainable products, emphasizing excellent service and community involvement |
2,765 |
| 22 |
ISG (Information Services Group)isg-one.com
Global AI-focused technology research and advisory firm helping organizations optimize technology investments and achieve operational excellence and growth. |
2,189 |
| 23 |
Barnesbarnesaero.com
A company known for persistent ingenuity, pushing boundaries to help customers make valuable impacts in global markets |
2,125 |
| 24 |
Cristaltronox.com
A leading producer of titanium dioxide and zircon products, with a global footprint in mining, processing, and sale of mineral sands |
2,050 |
| 25 |
Clipper Logistics plcgxo.com
Specializes in contract logistics services as part of the world's largest pure-play contract logistics company, GXO. |
1,472 |
| 26 |
GeneDxgenedx.com
Specializing in genetic diagnosis, offering exome and genome tests to provide personalized health plans, accelerate drug discovery, and improve health system efficiencies |
1,260 |
| 27 |
BlueTriton Brandsbluetriton.com
A leading provider of responsibly sourced spring and purified water products, promoting sustainability through natural resource management and community engagement |
1,249 |
| 28 |
MannKind Corporationmannkindcorp.com
This company focuses on developing and commercializing therapeutic products and devices for endocrine and orphan lung diseases, aiming to improve patients' lives |
833 |
| 29 | 
Intercontinental Hotel Group
Hospitality company based in Hartford, Connecticut, specializing in hotel services |
778 |
| 30 |
Photronicsphotronics.com
Industry leader in designing, developing, and producing reticles and photomasks for semiconductor and microelectronic applications with nine global manufacturing facilities |
640 |
| 31 |
Ruger Firearmsruger.com
Manufactures rugged, reliable firearms for commercial sporting market with nearly 700 variations across 40 product lines, emphasizing responsibility. |
629 |
| 32 |
ReneSola Ltd.emeren.com
Global solar project developer and operator with operations in over 10 countries, formerly known as ReneSola Power Ltd, now rebranded as Emeren Group Ltd |
580 |
| 33 |
Weeden & Co.pipersandler.com
A trusted institutional trading firm since 1922, offering premier execution services with a focus on client relationships, senior management involvement, and a partnership-based culture |
75 |
| 34 |
The Travelers Companies, Inctravelers.com
A Georgia-based insurance company providing insurance services from their headquarters in Augusta, United States |
19 |
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 24, 2026.
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- Financial services firms in Connecticut 132
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- Critical infrastructure operators in Connecticut 61
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- Venture capital and private equity firms in Connecticut 59
- Manufacturers in Connecticut 49
- Retail chains in Connecticut 48
- Healthcare providers in Connecticut 48
- Education providers in Connecticut 44
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- Aerospace and defence companies in Connecticut 39
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- Contract manufacturers in Connecticut 33
- Energy companies in Connecticut 29
- Manufacturing companies in Connecticut 28
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- Venture Capital and Private Equity Principals companies in Connecticut 27
- IT services companies in Connecticut 26
The same list elsewhere in United States
- Publicly traded companies in the United States 1,661
- Publicly traded companies in California 249
- Publicly traded companies in Texas 188
- Publicly traded companies in New York State 148
- Publicly traded companies in Illinois 89
- Publicly traded companies in Florida 78
- Publicly traded companies in Pennsylvania 64
- Publicly traded companies in Georgia 61
- Publicly traded companies in Ohio 57
- Publicly traded companies in Massachusetts 56
- Publicly traded companies in Virginia 55
- Publicly traded companies in North Carolina 52
- Publicly traded companies in New Jersey 50
- Publicly traded companies in Colorado 38
- Publicly traded companies in Arizona 37
- Publicly traded companies in Washington State 37
- Publicly traded companies in Alabama 34
- Publicly traded companies in Michigan 31
- Publicly traded companies in Tennessee 29
- Publicly traded companies in New York 120
- Publicly traded companies in Houston 71
- Publicly traded companies in Chicago 45
- Publicly traded companies in San Francisco 45
- Publicly traded companies in Atlanta 37