Founded in 1931, Diploma PLC is a leading British value-add distribution group headquartered in London, England, U.K. The company is historically recognized for its decentralized and acquisition-led development of specialist businesses supplying mission-critical products and services to technically demanding end markets. Today, Diploma operates through three sectors—Controls, Seals, and Life Sciences—and serves customers across areas including aerospace, defense, infrastructure, healthcare, water treatment, and industrial applications. In 2025, the group employed approximately 3,300 colleagues across its businesses, principally in North America, the United Kingdom, Europe, and Australia. For the year ended September 30, 2025, Diploma reported revenue of GBP 1,524.5 million, reflecting its position as one of the United Kingdom’s most established specialist distribution and value-add industrial groups.
Updated 2026-03-20