New Delhi, Feb. 13 -- When Tata Consultancy Services Ltd (TCS) last month disclosed a Rs.2,100 crore-plus profit hit from the new labour codes, that was only the beginning.

Of India's top 30 companies, 25 that have reported the impact of the amended labour regime suffered a nearly Rs.12,000-crore blow to their December quarter profits, a Mint analysis showed. The rules mandate higher social security contributions from both employers and employees, and also increase retirement benefits.

While the provisions stemming from the labour code accounted for just 7.70% the 25 companies' aggregate Q3 profit, this won't be a one-time cost.

Consulting firms caution that wage bills are set to increase even as India Inc.'s margins are under pressure...