EY Thailand (Ernst & Young)
EY Thailand (Ernst & Young) is the Thai member firm of the EY global network, one of the Big 4 professional services firms. Provides audit, tax, strategy and transactions, and consulting services in Thailand. Known for consumer, retail, technology, and healthcare sector audit mandates. Advisory practices include M&A due diligence, digital transformation, ESG reporting, and tax advisory. Regulated by the Federation of Accounting Professions (FAP) and the SEC for listed-company audit. Competes with PwC, Deloitte, and KPMG Thailand across enterprise audit and advisory work.
Snapshot
Headline numbers a buyer checks first.
Thailand revenue (est.)
~THB 5-7B
FY2024
Estimated; member firm financials not publicly disclosed
Thailand headcount (est.)
~1,500
2025
Across audit, tax, consulting, strategy and transactions
Service lines
4
Ongoing
Audit, Tax, Consulting, Strategy and Transactions
Bangkok office
1 primary office
Ongoing
Lake Rajada Office Complex, Bangkok
Profile overview
EY Thailand (Ernst & Young) is the Thai member firm of the EY global network, one of the Big 4 professional services firms. Provides audit, tax, strategy and transactions, and consulting services in Thailand. Known for consumer, retail, technology, and healthcare sector audit mandates. Advisory practices include M&A due diligence, digital transformation, ESG reporting, and tax advisory. Regulated by the Federation of Accounting Professions (FAP) and the SEC for listed-company audit. Competes with PwC, Deloitte, and KPMG Thailand across enterprise audit and advisory work.
Service lines
Audit and assurance
Listed-company and MNC statutory audit
EY Thailand holds audit mandates for major Thai listed companies in consumer, retail, technology, and healthcare sectors. Regulated by FAP and SEC; listed-company audit rotation creates periodic mandate competition across Big 4 firms. EY's technology-sector audit depth reflects its global EY Assurance brand positioning.
Tax advisory
Corporate tax, transfer pricing, VAT
Tax advisory services for multinational subsidiaries, Thai conglomerates, and private-equity transactions. Covers corporate income tax, transfer-pricing documentation, VAT, international tax treaty analysis, and BEPS compliance. EY's global tax network provides access to multi-jurisdiction structuring expertise relevant to Thai MNC clients.
Strategy and transactions
M&A due diligence and deal advisory
EY's Strategy and Transactions practice covers financial and commercial due diligence for M&A, private-equity, and corporate-divestiture transactions. Active in Thai consumer, retail, healthcare M&A advisory. Cross-border deal support leverages EY's ASEAN, Greater China, and Japan practices for Thai-outbound and inbound-foreign-investor mandates.
Consulting
Digital transformation, ESG, supply chain
EY Consulting in Thailand covers digital transformation (ERP implementation, analytics, cloud migration), ESG reporting and assurance, and supply-chain resilience. Growing practice in Thai banking, insurance, and manufacturing sectors as large corporates invest in digital-operations upgrades.
Big 4 professional services comparison — Thailand
Approximate FY2024 positioning and sector strengths
PwC Thailand
Audit sector strength
Consumer, retail, technology, healthcare
Advisory focus
M&A, digital, ESG
Notable affiliation
Active in tech-sector mandates
Audit sector strength
Industrial, real estate, energy
Advisory focus
Infrastructure, deal advisory
Notable affiliation
KBank affiliate relationship
| Firm | Audit sector strength | Advisory focus | Notable affiliation |
|---|---|---|---|
| PwC Thailand | Banking, financial services, insurance | Deals, digital, risk | SCB, KBANK audit mandates |
| Deloitte Thailand | Energy, telecom, hospitality | Technology, risk consulting | PTT, AIS mandates |
| EY Thailand | Consumer, retail, technology, healthcare | M&A, digital, ESG | Active in tech-sector mandates |
| KPMG Thailand | Industrial, real estate, energy | Infrastructure, deal advisory | KBank affiliate relationship |
Key drivers 2025-2026
ESG assurance
Sustainability reporting demand
Thai SEC's mandatory ESG reporting requirements for listed companies and SET-listed ESG disclosure expansion are driving demand for ESG assurance and advisory services. EY is positioning its global ESG practice in Thailand to capture assurance mandates from large Thai corporations with international investor bases.
Digital
AI and cloud transformation advisory
Thai enterprise investment in AI, cloud migration, and digital-core transformation creates advisory demand for large professional services firms. EY's EY.ai and technology consulting capabilities are being deployed in Thai banking, logistics, and manufacturing sector transformation engagements.
Audit rotation
Listed-company audit mandate cycle
Thai SEC audit-firm rotation rules create periodic audit mandate competition among Big 4 firms. EY's consumer and technology audit-sector positioning means it competes for mandates at major Thai consumer conglomerates, e-commerce platforms, and technology companies when rotation cycles occur.
Where this profile is featured
Reports that reference this entity in their operator concentration or analysis.
Featured in
The Thai Audit Market: Big-Four, Mid-Tier, and CPA Thailand Reserva...
Big-Four; advisory, consulting strong practice.
Featured in
Thai Management Consulting: Big-4 vs Local Firms and Sector Mix
Big-Four; advisory, consulting strong practice.
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Reports featuring this profile
The Thai Audit Market: Big-Four, Mid-Tier, and CPA Thailand Reservation
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Sits alongside 4 other Atlas profilesThai Management Consulting: Big-4 vs Local Firms and Sector Mix
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Sits alongside 5 other Atlas profilesThai Transfer Pricing and Country-by-Country Reporting (CbCR)
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Deloitte Thailand
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KPMG Thailand
Big 4 audit and advisory firm in Thailand; known for industrial, energy, and real-estate sector audit mandates.
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PricewaterhouseCoopers Thailand (PwC)
Big 4 audit and advisory firm in Thailand; statutory auditor for major SET-listed companies and MNC subsidiaries.