The KOSPI 200 brings together 200 leading companies listed on the Korea Exchange and spans some of South Korea’s largest industrial, technology, financial and consumer groups.
Big4News identified the current FY2026 external auditor of every constituent, together with the first financial year of the present audit relationship where this could be established reliably and the latest available audit fee.
The dataset reflects the KOSPI 200 at September 2026. Audit fees are shown in South Korean won.
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 and standardises the data across the series, see Who Audits? Sources & Methodology.
KOSPI 200 audit market share
EY leads, but the Big Four do not have the market entirely to themselves.
EY is the largest auditor in the KOSPI 200, with 60 of the 200 mandates, equivalent to a 30% market share.
KPMG follows with 54 companies, or 27%, while PwC audits 46, or 23%.
Deloitte is considerably smaller, with 27 mandates and a 13.5% share.
Together, the Big Four audit 187 of the 200 companies, or 93.5%.
That leaves 13 companies — 6.5% of the index — audited by firms outside the Big Four.
EY’s lead is driven by several major sectors
The overall market-share figures conceal substantial differences between sectors.
Industrials are the largest group in the dataset, with 42 companies. KPMG leads there with 16 mandates, followed by EY with 12, PwC with eight and Deloitte with five.
Materials tell a different story. Of the 39 materials companies, EY audits 15 — considerably more than KPMG’s nine. Seven materials companies use firms outside the Big Four, making the sector one of the clearest areas of challenger participation.
EY is also particularly strong in healthcare, auditing nine of the 14 healthcare companies.
PwC leads financial services. It audits nine of the 22 financial companies, compared with five for KPMG and four each for EY and Deloitte.
KPMG has the strongest position in information technology, where it audits seven of 17 companies. Its clients include two of the most prominent semiconductor companies in the index, Samsung Electronics and SK Hynix.
Audit fees put KPMG in first place
Market share changes again when the size of identified audit fees is considered.
Big4News identified a current audit fee for 182 of the 200 companies.
Together, those fees amount to approximately KRW 187.8 billion.
KPMG-audited companies account for approximately KRW 60.2 billion, or 32.1% of the identified total.
PwC follows with about KRW 52.8 billion, or 28.1%, while EY accounts for approximately KRW 44.5 billion, or 23.7%.
Deloitte accounts for around KRW 25.7 billion, or 13.7%.
The ten other audit firms represented in the index collectively account for approximately KRW 4.6 billion, or 2.4% of the identified fee pool.
That produces a different ranking from the number of mandates. EY leads by client count, but KPMG holds the largest share of identified audit fees.
Korea has an exceptionally young auditor-tenure profile
Big4News established the first financial year of the current audit relationship for 199 of the 200 companies.
More than three-fifths of those relationships began in just the past two financial years: 62 began in 2025 and another 61 in 2026.
A further 34 began in 2024 and 29 in 2023.
That means 186 of the 199 precisely dated relationships — 93.5% — began in 2023 or later.
Only 13 date from before 2023.
The oldest precisely established current relationship in the dataset begins in 2020, when PwC became auditor of Korea District Heating. One further relationship, S-Oil with PwC, can be traced much further back, but Big4News leaves its “Since” field blank because the true first financial year of the continuous engagement could not be established reliably.
Korea’s auditor-designation system helps explain the turnover
The unusually short tenures are closely connected to South Korea’s regulatory framework.
Under Korea’s periodic auditor-designation system, listed companies generally select their external auditor for six years before the financial regulator appoints an auditor for the following three years. The system was introduced to strengthen auditor independence. South Korean rules also generally require listed companies to retain the same appointed auditor for three consecutive financial years.
The framework means that three-year audit periods appear repeatedly throughout the KOSPI 200 data.
About the data
The dataset reflects the KOSPI 200 constituent universe at September 2026 and contains 200 companies.
For more detail on the methodology used across the series, see Who Audits? Sources & Methodology.
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