MCK vs CI Comparison

McKesson is one of three leading pharmaceutical wholesalers in the US engaged in sourcing and distributing branded, generic, and specialty pharmaceutical products to pharmacies (retail chains, independent, and mail order), hospitals networks, and healthcare providers. Along with Cencora and Cardinal Health, the three account for over 90% of the US pharmaceutical wholesale industry. Outside the US market, McKesson engages in pharmaceutical wholesale and distribution in Canada. Additionally, the company supplies medical-surgical products and equipment to healthcare facilities and provides a variety of technology solutions for pharmacies.

Cigna primarily provides pharmacy benefit management and health insurance services. Its PBM and specialty pharmacy services, which were greatly expanded by its 2018 merger with Express Scripts, are mostly sold to health insurance plans and employers. Its largest PBM contract is with the Department of Defense, and it recently won a multiyear deal with top-tier insurer Centene. In health insurance and other benefits, Cigna primarily serves employers through self-funding arrangements, and the company operates mostly in the US with 16 million US and 2 million international medical members covered as of December 2025.