| # | Company | Employees |
|---|---|---|
| 1 | 64,159 | |
| 2 | 41,860 | |
| 3 | 33,277 | |
| 4 |
Wabtec Corporationwabteccorp.com
Provider of equipment, systems, digital solutions, and services for freight rail, transit, mining, industrial, and marine transportation sectors. |
27,000 |
| 5 |
American Eagle Outfitters Inc.aeo-inc.com
Global omni-channel retailer offering high-quality apparel, intimates, activewear, and personal care products through diverse brands focused on optimistic self-expression and social responsibility. |
22,832 |
| 6 |
University of Pittsburghpitt.edu
Top-ranked public institution in Pennsylvania, member of leading research universities Known for innovative discoveries and shaping future paths |
19,349 |
| 7 |
Viatrisviatris.com
Global healthcare company providing extensive medicine portfolio and supply chain to deliver high-quality medicines addressing diverse health needs worldwide. |
17,886 |
| 8 | 17,780 | |
| 9 |
Highmark Healthhighmarkhealth.org
Provides health insurance, care delivery, population health management, dental solutions, reinsurance, and innovative technology to millions of customers across the nation. |
15,876 |
| 10 | 12,502 | |
| 11 |
Allegheny Health Networkahn.org
Integrated healthcare delivery system with hospitals, medical centers, wellness pavilions, and numerous physician practices serving Western Pennsylvania. |
11,676 |
| 12 |
Carnegie Mellon Universitycmu.edu
University providing education that develops problem solvers, innovators, and pioneers in technology and the arts, ready for careers. |
11,021 |
| 13 | 10,422 | |
| 14 |
Howard Hanna Real Estate Serviceshowardhanna.com
Provider of real estate, title, insurance, and mortgage services in 13 states with over 480 offices and 15,000 sales associates |
8,768 |
| 15 |
F.N.B. Corporationfnb-online.com
Diversified financial services company offering commercial banking, consumer banking, wealth management, and insurance solutions across multiple U.S. states. |
7,832 |
| 16 |
Highmarkhighmark.com
A leading health insurance organization delivering high-quality, accessible, and affordable solutions to 68 million members in multiple states |
7,672 |
| 17 |
Howmet Aerospacehowmet.com
A global provider of advanced engineered solutions for aerospace and transportation industries, specializing in jet engine components, aerospace fastening systems, and titanium structural parts |
7,402 |
| 18 |
United States Steel Corporationussteel.com
Developing and delivering profitable, next-generation steel solutions focused on safety and meeting current and future customer needs. |
6,794 |
| 19 |
Kennametalkennametal.com
A global industrial technology leader specializing in advanced materials innovation, tooling, and wear-resistant solutions to enhance productivity for various industries |
6,659 |
| 20 |
K&L Gatesklgates.com
Global law firm providing expert legal counsel across corporate, regulatory, and litigation matters for diverse industries and public sector clients. |
4,682 |
| 21 |
Aerie by AEO, Inc.ae.com
Designing intimates, apparel, activewear, and swimwear with a focus on empowering women through inclusivity, confidence, and embracing the natural self |
4,682 |
| 22 |
Arconicarconic.com
A leading provider of aluminum products for automotive, aerospace, transportation, industrial, packaging, and construction markets, committed to innovation and advancement |
4,672 |
| 23 |
NEP Group, Inc.nepgroup.com
Worldwide live sports and entertainment production services using advanced technology and expert teams to deliver reliable, innovative media solutions for major events. |
4,569 |
| 24 |
UPMC Health Planupmchealthplan.com
A leading health insurer offering quality health insurance plans for individuals, families, and businesses, with a focus on providing top-ranked care and innovative wellness programs |
4,550 |
| 25 |
Michael Baker Internationalmbakerintl.com
Comprehensive engineering, consulting, and technology services for infrastructure projects including design, planning, environmental, and program management across multiple sectors. |
4,466 |
| 26 | 3,969 | |
| 27 |
Anixteranixter.com
A global provider of distribution, logistics, and supply chain solutions, offering electrical, communications, security, and safety services to businesses worldwide |
3,757 |
| 28 |
UPMC Children's Hospital of Pittsburghchp.edu
A leader in treating childhood conditions, developing therapies, educating pediatricians, and advancing research with strong community support since 1890 |
3,489 |
| 29 |
Duquesne Universityduq.edu
A top Catholic university since 1878, preparing 8,000 students through award-winning faculty, horizon-expanding education, and commitment to equity |
3,431 |
| 30 |
Allegheny Countyalleghenycounty.us
Regional economic development focusing on advanced manufacturing, technology, healthcare, finance, education, and environmental solutions supporting thriving businesses and entrepreneurs. |
3,419 |
| 31 |
Excelitas Technologies Corp.excelitas.com
Provider of advanced photonic technologies specializing in sensing, detection, imaging, optics, and specialty illumination for diverse global industries. |
3,129 |
| 32 |
Pittsburgh Public Schoolspghschools.org
A school district in Pittsburgh serving 25,000 students from Pre-K to Grade 12, emphasizing on academic excellence and preparing students for future success |
2,972 |
| 33 |
Duolingoduolingo.com
The company is dedicated to providing free language education through a popular app, using data insights to improve learning effectiveness |
2,845 |
| 34 |
FOREVERforever.com
Digitize and preserve physical memories forever with secure storage, photo organization software, printing services, and personalized photo gifts for generations to enjoy |
2,807 |
| 35 |
Leading light It
The company offers digital marketing services to help businesses grow and succeed online |
2,709 |
| 36 |
Auroraaurora.tech
Aurora provides self-driving technology for transportation, making it safer, more accessible, and efficient for various vehicle types and industries |
2,568 |
| 37 |
Matthews Internationalmatw.com
Global provider of precision industrial technologies and memorialization products, serving industries and funeral homes with innovative, efficient solutions. |
2,226 |
| 38 |
University of Pittsburgh School of Medicinemedschool.pitt.edu
Training physician leaders and scientists to improve health, advance research, promote equity, and collaborate internationally in medicine and education. |
2,199 |
| 39 |
City of Pittsburghpittsburghpa.gov
City with rich industrial history, now thriving in healthcare, education, technology, and financial services, featuring diverse neighborhoods and vibrant culture. |
2,011 |
| 40 |
Industrial Coatingsppg.com
Global provider of advanced coatings, paints, and specialty materials focused on protecting and enhancing industrial products and landmarks. |
1,830 |
| 41 | 1,816 | |
| 42 |
Federated Hermesfederatedhermes.com
Global investment management firm providing equity, international, fixed income, alternative, and money market investment strategies since 1955. |
1,813 |
| 43 | 1,776 | |
| 44 |
St. Moritz Security Services, Inc.smssi.com
A veteran-owned security company founded in 1982, providing proactive security solutions with a dedicated staff of professionals to government and industry clients |
1,583 |
| 45 | 1,512 | |
| 46 |
System Onesystemone.com
Specialized provider of outsourced services and workforce solutions for critical infrastructure, technology, life sciences, and government sectors Offering staffing and technical expertise |
1,507 |
| 47 |
IMCimcdocs.com
Provider of productivity management services for employers, specializing in resolving health-related issues impacting workforce productivity through physician-to-physician approach |
1,497 |
| 48 |
Dollar Bankdollar.bank
An inclusive community bank investing in customers, empowering employees, and strengthening communities while prioritizing customer privacy and data protection |
1,442 |
| 49 |
Duquesne Light Companyduquesnelight.com
Providing safe, reliable electric service to over 600,000 customers in southwestern Pennsylvania with a focus on clean energy transition. |
1,428 |
| 50 |
St. Clair Healthstclair.org
An independent acute-care medical center in southwestern Pennsylvania, offering a wide range of high-quality health care services to the community |
1,408 |
| 51 |
Point Park Universitypointpark.edu
Urban university in Downtown Pittsburgh offering over 100 undergraduate and graduate programs in arts, business, communication, and performing arts Integrally linked with the city |
1,301 |
| 52 |
Buchanan Ingersoll & Rooney PCbipc.com
National law firm providing legal, business, regulatory, and government relations advice to clients in energy, finance, healthcare, and life sciences industries |
1,272 |
| 53 |
Automated Health Systemsautomated-health.com
Leading provider of health care services for low-income families & communities Specializing in administration of public health programs and career opportunities in the eastern US |
1,228 |
| 54 |
Instagram Marketing
Specializing in social media management, the expert helps businesses grow on Instagram by providing organic marketing strategies and targeted audience engagement |
1,206 |
| 55 |
Inctureincture.com
A digital systems company delivering intelligent applications and services to enhance lives and address complex business challenges at scale using SAP technology |
1,159 |
| 56 |
TMS International LLCtmsinternational.com
A global leader in providing on-site steel mill services, focused on safety, innovation, environmental protection, and creating value for customers through expertise and unrivaled service |
1,146 |
| 57 |
Community College of Allegheny Countyccac.edu
A nationally renowned two-year college offering a wide range of academic and career-based programs, serving over 25,000 students annually Graduates excel in various industries worldwide |
1,126 |
| 58 | 1,118 | |
| 59 |
Koppers Inc.koppers.com
A global wood preservation technology company creating environmentally responsible solutions for various industries, with a focus on safety and sustainability |
1,080 |
| 60 |
Software Engineering Institute | Carnegie Mellon Universitysei.cmu.edu
The company conducts research on software engineering, cybersecurity, and AI, creating and testing innovative technologies for government and private industry since 1984 |
1,061 |
| 61 |
CLGalula.clg.com
A consulting firm specializing in behavior-based strategy execution, performance improvement, and leader-led change for Fortune 500 companies Applied Behavioral Science principles drive results |
1,042 |
| 62 |
Chatham Universitychatham.edu
An educational institution offering over 40 majors focused on health, sustainability, arts, sciences, and business, with a dedication to environmental studies |
1,037 |
| 63 |
Talogytalogy.com
Experts in talent management crafting solutions for screening, selecting, developing, and engaging talent worldwide using psychology and technology for data-driven decisions |
1,036 |
| 64 | 1,028 | |
| 65 |
UPMC Hillman Cancer Centerhillmanresearch.upmc.edu
An NCI-designated cancer center affiliated with a university, providing high-level clinical care, research, and education to cancer patients and professionals |
1,028 |
| 66 |
PITT OHIOpittohio.com
Transportation and logistics services including LTL freight, expedite, truckload, warehousing, distribution, and sustainable supply chain solutions. |
1,018 |
| 67 |
Pittsburgh Piratespirates.com
Professional baseball team located in Pittsburgh, Pennsylvania, with a rich history and passionate fan base Home games at PNC Park, known for its tradition and scenic views |
976 |
| 68 |
Confluenceconfluence.com
provides technology solutions for investment management, offering products for performance, risk, data, regulatory, and investor reporting needs globally |
929 |
| 69 |
Liberty Tire Recycling, LLClibertytire.com
Reclaims over four billion pounds of scrap tires annually, transforming waste into sustainable products through a network of North American processing facilities. |
927 |
| 70 |
SMS group USAsms-group.com
A leader in providing new equipment, maintenance, and spare parts services for metals producers in North America and globally |
919 |
| 71 |
Pittsburgh Regional Transitrideprt.org
Operate and maintain bus, rail, and incline transit services in the Pittsburgh metropolitan area with a workforce of 2,600 employees. |
892 |
| 72 |
Caliber Technologiescaliberuniversal.com
Leading provider of integrated quality management platform solutions for regulated industries, specializing in Life Sciences and Pharmaceuticals, with a global presence |
885 |
| 73 |
United Steelworkers (USW)usw.org
An organization with 12 million members in North America and the Caribbean, focused on improving jobs, securing a better future, and promoting fairness and equality |
885 |
| 74 |
COGENT Infotechcogentinfo.com
A global consulting firm specializing in digital transformation, workforce solutions, and research & insights, with a focus on nurturing top industry talent |
869 |
| 75 |
Carlow Universitycarlow.edu
A private Catholic university in Pittsburgh offering undergraduate and graduate programs in health, education, and arts, promoting ethical leadership and social justice |
861 |
| 76 |
North Allegheny School Districtnorthallegheny.org
A suburban school district near Pittsburgh serving over 45,000 residents with a commitment to excellence, diversity, and collaboration for student success |
850 |
| 77 |
Rivers Casino & The Landing Hotel Pittsburghriverscasino.com
A vibrant casino offering dining, entertainment, events, and accommodations, with a focus on community outreach programs and diverse employment opportunities Apply online today |
843 |
| 78 |
HarbisonWalker Internationalthinkhwi.com
A global leader in refractory products delivering solutions to industries worldwide with over 150 years of excellence in performance and value |
809 |
| 79 |
Carnegie Learningcarnegielearning.com
Innovative K-12 education technology company providing curriculum, professional learning, and tutoring solutions to support deep understanding and real-world applications |
782 |
| 80 |
Aerotech, Inc.aerotech.com
This company specializes in designing and manufacturing precision motion control systems for various industries and research institutions worldwide |
760 |
| 81 |
Northwood Realty Servicesthepreferredrealty.com
A real estate company with over 50 years of experience, specializing in buying and selling homes in Western Pennsylvania and Eastern Ohio with a customer-first approach |
758 |
| 82 |
Pressley Ridgepressleyridge.org
Supporting individuals and families facing challenges by empowering them through collaborative relationships, diverse services, and a culture of respect and inclusivity |
757 |
| 83 |
Industrial Scientificindsci.com
Innovative company designs gas detection products to protect workers globally, pioneering technologies for detecting and responding to hazardous conditions in real time |
755 |
| 84 |
Primanti Bros. Restaurant and Barprimantibros.com
An iconic restaurant known for its oversized sandwiches with hand sliced meats, house made slaw, and fresh cut fries, also offering pizza, wings, salads, and craft beers |
731 |
| 85 |
JENNMARjennmar.com
Global leader in ground control technology for mining, tunneling, and civil construction industries, offering a wide range of quality products and services worldwide |
724 |
| 86 |
RoadRunnerroadrunnerwm.com
Innovative waste and recycling company offering tech-enhanced services to streamline operations, drive cost savings, and increase landfill diversion for zero waste goals |
693 |
| 87 |
LB Fosterlbfoster.com
A leading provider of materials for transportation, construction, recreation, and agriculture projects, offering engineering, manufacturing, distribution, and service solutions globally |
692 |
| 88 |
North American Dental Group (NADG)nadentalgroup.com
Provides comprehensive support to over 230 dental practices, enabling affiliated dentists to focus on patient care with clinical autonomy, emphasizing empathy, compassion, and care. |
692 |
| 89 |
Brightside Academybrightsideacademy.com
This company offers quality education and child care services to children of all backgrounds, providing early education, summer camp, and before/after school programs |
689 |
| 90 |
PANTHERx Rare Pharmacypantherxrare.com
A pioneering rare disease pharmacy in Pittsburgh, redefining specialty care with innovative RxARECAREโข program and national recognition for excellence |
689 |
| 91 |
Carmeuse Americascarmeuse.com
A leading manufacturer of lime and limestone products offering integrated services to optimize processes and provide solutions across various industries |
687 |
| 92 |
Eckert Seamanseckertseamans.com
A national law firm providing a full range of legal services nationwide to businesses, institutions, municipalities, and individuals in various practice areas |
685 |
| 93 |
Chromaloxchromalox.com
Innovative developer of advanced thermal technologies for industrial heating applications worldwide, with a focus on exceeding specifications and reducing operating costs |
682 |
| 94 |
ePS (eProductivity Software)epssw.com
A global provider of industry-specific business and production software for packaging and print industries, specializing in integrated solutions for revenue growth and efficiency |
682 |
| 95 |
ZOLL Cardiac Management Solutionscardiac.zoll.com
Provider of innovative technologies improving insights and outcomes in various cardiac care paths, focusing on cardiac management solutions |
674 |
| 96 |
Pittsburgh Mercypittsburghmercy.org
This company provides mental health services, alcohol/drug treatment, programs for intellectual disabilities, and support for caregivers in Southwestern Pennsylvania |
669 |
| 97 |
Schneider Downslinktr.ee
A top public accounting firm offering a wide range of services to clients across various industries worldwide through five business units |
661 |
| 98 |
PMC (Now a part of Michael Baker International)mbakerintl.com
A leading provider of engineering, development, intelligence, and technology solutions with global reach, offering services in infrastructure and asset projects worldwide |
636 |
| 99 |
Pittsburgh Steelerssteelers.com
Established NFL franchise with a rich history, multiple Super Bowl championships, and strong community involvement, embodying consistency, loyalty, and success |
625 |
| 100 |
Workpartnersworkpartners.com
The company focuses on human capital management through people activation, offering services in analytics, advocacy, absence management, and technology solutions |
624 |
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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 9, 2026.
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- The largest companies in the United States 91,636
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