Buy-Side Due Diligence Checklist

Core Workstreams (mirror sell-side)

The buyer's checklist starts from the sell-side checklist and adds the items below.

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Synergy and Integration

• Cost synergy register and quantification.
• Revenue synergy register and quantification.
• Integration plan: organisational, IT, ERP, brand.
• Day-1 readiness checklist.
• Carve-out separation plan (if applicable).

Antitrust / Merger Control

• Market shares and competitive landscape.
• Joint-revenue analysis.
• Filing strategy across EU, UK, DE, FR, IT, ES, US, etc.
• Customer reaction risk.

Financing

• Debt commitments and term sheets.
• Equity financing position.
• Working capital at close.
• Bridge financing terms.

Specialist Workstreams

• Environmental: site-by-site Phase I, contingent liabilities.
• Tax: structuring memo, deferred tax review.
• IT: cyber posture, integration cost.
• Commercial: customer reference calls.
• Operations: capacity, supplier dependencies.

Frequently Asked Questions

Further Reading

• M&A Data Room Checklist (Sell-Side)
• Due Diligence Data Rooms
• Papermark