Deloitte is entirely absent from the WIG20. At the September 2026 snapshot, none of Poland’s 20 blue-chip companies is audited by Deloitte. PwC leads the market with nine mandates, while Grant Thornton holds two — meaning the mid-tier firm has a larger WIG20 audit presence than Deloitte.
Who audits the world’s largest companies?
Explore the Big4News Who Audits? hub, which maps the audit firms behind the world’s leading stock-market indices — including auditor tenure, audit fees and Big Four audit market share.