The six largest audit firms in India by number of clients, audited 66% of the Nifty 500 companies as of 2025-26 according tot data from Primedatabase.

EY, KPMG, Deloitte, GT Group, BDO Group and PWC Group including their associates consulted 8% more companies at 779 clients in 2025-26 from 722 last year. BDO Group including its associates increased its client count the most by 17 companies in the past. Deloitte was the only group among the top six that lost six clients in a year, going by the data.

There are more than 900 audit firms in India with over 2,000 NSE listed clients. However, the top 10 of these firms audited 38% of the listed companies, signifying a sharp concentration at the top. Barring PwC, the others in the big four increased their auditing fee by at least 25% in 2024-25 as against 2023-24, Primedatabase said. Put together, the big four auditors earned ₹617 crore in auditing fees in fiscal 2024-25, which is more than 70% of the fees incomes of the top ten most earning companies.

“The dominance of Big 6 and Big 4 firms increases if we exclude the listed PSU banks, which the Big 6 do not audit, with them collecting 64 per cent and 54 per cent of the audit fee respectively,” Prime data said in its statement.