Who Owns McMaster-Carr?

McMaster-Carr Supply Company was founded in Chicago in 1901 by T.J. McMaster and F.H. Carr, initially supplying hardware and mechanical components to the machine shops and factories of the booming industrial Midwest. Through the early 20th century it built a reputation for carrying obscure parts that general hardware suppliers did not stock.

The defining artifact of the business became its catalog: a famously comprehensive yellow reference book that factory engineers and maintenance departments kept within reach for decades. By mid-century the catalog ran to thousands of pages and effectively functioned as an engineering reference, listing dimensions, materials, and specifications that made it the default sourcing document for American industry.

McMaster moved its headquarters to suburban Elmhurst, Illinois, and built regional distribution centers in Robbinsville, New Jersey; Santa Fe Springs, California; Douglasville, Georgia; and Aurora, Ohio, enabling next-day ground delivery to most of the country.

Its most consequential move was early digital adoption. McMaster launched online ordering in the 1990s and built what is widely regarded as the best e-commerce experience in industrial distribution: parametric search, CAD downloads for millions of parts, and specification filters that competitors including Grainger, MSC, and Fastenal spent years imitating. That digital edge sustained premium pricing without field sales reps, keeping the company lean as revenue passed an estimated billion dollars. It remains privately held with no public plans to change that status.