Mandatory audit under Section 44AB above turnover thresholds.
Tax Audit is required if business turnover > ₹1 crore (₹10 cr if cash transactions ≤ 5%) or professional gross receipts > ₹50 lakh. Audit conducted by a CA, who files Form 3CA/3CB + Form 3CD. Due 30 September.
Larger businesses + high-income professionals.