The FTSE MIB comprises 40 of the largest and most liquid companies listed on Borsa Italiana and provides a snapshot of the leading end of Italy’s public-company audit market.
Big4News identified the current statutory auditor of every constituent, the first financial year of the present audit engagement, and the latest available audit fee where this could be established to publication standard.
The dataset reflects the FTSE MIB at 30 September 2026. Audit fees are shown in euros.
The table is sortable. Click any column heading to reorder the data by company, sector, auditor, tenure or audit fee.
For details on how Big4News verifies auditors, tenure and audit fees across the series, see Who Audits? Sources & Methodology.
FTSE MIB audit market share
KPMG and PwC lead, with Deloitte close behind.
The FTSE MIB audit market is overwhelmingly controlled by the Big Four, which audit 39 of the index’s 40 companies.
KPMG and PwC each audit 11 companies, giving both firms a 27.5% market share. Deloitte is close behind with 10 mandates, or 25%. EY audits seven companies, equivalent to 17.5%.
The only company not audited by the Big Four is Tenaris, whose auditor is Forvis Mazars.
Financial services are split across all four firms
Financials are the largest sector in the FTSE MIB dataset, with 11 companies, and the audit mandates are spread across all four Big Four firms.
KPMG audits BPER Banca, FinecoBank, Generali and UniCredit.
PwC audits Banca Mediolanum, Banca Monte dei Paschi di Siena and Mediobanca.
EY audits Azimut, Intesa Sanpaolo and Unipol.
Deloitte audits Banco BPM.
The distribution is significant because financial institutions include some of the largest and more complex audit engagements in the index, yet no single firm dominates the sector.
Elsewhere, the pattern is less balanced.
PwC audits all three information-technology companies in the dataset — Nexi, STMicroelectronics and Technoprobe.
The six utilities are split evenly between KPMG and Deloitte, with three mandates each.
Among the six industrial companies, Deloitte holds three mandates, while EY, KPMG and PwC each audit one.
Auditor rotation has produced a relatively young set of engagements
The FTSE MIB stands out for the relatively recent start dates of many of its current audit relationships.
Eleven current engagements began in 2024 or later.
They include:
Hera — KPMG from 2024
INWIT — KPMG from 2024
Stellantis — Deloitte from 2024
A2A — KPMG from 2025
Prysmian — PwC from 2025
Tenaris — Forvis Mazars from 2025
Avio — KPMG from 2026
Banco BPM — Deloitte from 2026
BPER Banca — KPMG from 2026
Mediobanca — PwC from 2026
STMicroelectronics — PwC from 2026
At the other end of the spectrum, the earliest current engagements in the dataset date only to 2019.
Those include Amplifon with KPMG, Eni and Nexi with PwC, Saipem with KPMG and Telecom Italia with EY.
That is a markedly different tenure profile from markets where individual audit relationships can extend back several decades.
European rules for public-interest entities place limits on the duration of statutory audit engagements. Under the EU Audit Regulation, the standard maximum duration of an audit-firm engagement is ten years, subject to extensions under specified circumstances.
The FTSE MIB data reflects that environment. Audit mandates change hands regularly, and none of the current relationships in the index predates 2019.
Audit fees change the ranking
The picture looks different when the market is viewed through disclosed audit fees rather than the number of mandates.
Big4News identified a current audit fee for 34 of the 40 companies. Across those engagements, the disclosed fees total approximately €232.3 million.
KPMG-audited companies account for around €76.9 million, or 33.1% of the identified total.
Deloitte ranks second by disclosed fees at approximately €61.6 million, or 26.5%.
PwC accounts for about €46.8 million, or 20.1%, while EY accounts for approximately €45.7 million, or 19.7%.
Forvis Mazars accounts for around €1.3 million, or 0.5%.
That produces a different ordering from the mandate count. KPMG and PwC are tied for first by number of clients, but KPMG has a substantially larger share of the identified fee pool.
About the data
The dataset reflects the FTSE MIB constituent set at 30 September 2026. Borsa Italiana describes the FTSE MIB as comprising 40 of the most liquid and highly capitalised shares listed on Euronext Milan and Euronext MIV Milan.
For more detail on how the series is researched and standardised, see Who Audits? Sources & Methodology.
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