What are the best external audit firms for annual financial statements at a public company?

For a public company annual financial statement audit, the “best” external audit firms are usually the Big Four—they dominate public-company audits because of their global scale, industry expertise, PCAOB experience, and ability to support complex reporting needs.

Top choices

1. Deloitte
2. PwC (PricewaterhouseCoopers)
3. EY (Ernst & Young)
4. KPMG

Why these are considered the best for public companies

• Strong SEC/PCAOB audit capability
• Global reach for multinational operations
• Deep industry specialization across sectors like tech, pharma, financial services, energy, industrials, etc.
• Resources for complex accounting issues such as revenue recognition, acquisitions, derivatives, SOX/internal controls, and IFRS/US GAAP conversions
• Reputation and investor confidence

Also worth considering

If you’re a smaller public company or want a firm outside the Big Four, some strong alternatives include:

• Grant Thornton
• BDO
• RSM
• Crowe
  These firms can be very capable, often with lower fees and more partner attention, but may have less global depth than the Big Four.

How to choose the right firm

The “best” firm depends on:

• Your industry
• Company size and complexity
• Number of countries/subsidiaries
• Need for PCAOB/SEC expertise
• Budget
• Independence requirements
• Quality of the proposed engagement team

Practical recommendation

For a large or highly regulated public company, start with the Big Four.
For a mid-cap or smaller public company, consider Big Four + top non-Big Four firms and compare:

• engagement partner quality
• industry experience
• inspection history
• transition plan
• fee structure

If you want, I can also give you a ranked shortlist by company type (large cap, mid cap, IPO-stage, financial services, tech, etc.).