Grant Thornton has been pressing the Financial Reporting Council to restore it to the top tier of audit firms, subject to the greatest regulatory scrutiny, as it attempts to repair its reputation and reverse a years‑long retreat from high‑risk work. The UK’s sixth‑largest accounting firm dropped more than 70 per cent of its top audit clients between 2016 and 2022 after millions of pounds in fines and legal cases over shortcomings at Patisserie Valerie, Sports Direct and Interserve.

The 2023 demotion from “tier one” removed the firm from the regulator’s most intensive oversight and was misread by prospective clients as a quality signal, hurting its ability to win large mandates. Since 2021 Grant Thornton has been fined £4mn and repeatedly asked the FRC to reinstate its tier‑one status or publish a standalone audit quality report; tier‑one status is viewed as a security layer for big clients such as Frasers Group, which is seeking a Big Four auditor.

After selling a stake to private equity group Cinven in 2024, Grant Thornton began rebuilding its public‑interest‑entity (PIE) audit practice, targeting 10 per cent annual fee growth and pursuing more than 120 tenders. It has won new mandates from Raspberry Pi and SSP Group. The FRC is reviewing its tiering system and may drop formal tiers, a move former executive Sarah Rapson said turned the system into a league table.

The audit market remains dominated by the Big Four — Deloitte, EY, KPMG and PwC — and the scarcity of challenger firms is a longstanding concern. Wendy Russell, UK head of audit at Grant Thornton, said having challengers is “vital” and the firm’s strategy focuses on clients that fit its purpose rather than chasing volume.