The three limits
Schedule III, table item 11 of the Income-tax Act, 2025 is the HRA exemption. It was Section 10(13A) and Rule 2A. Rule 279 of the Income-tax Rules, 2026 says you take the least of the HRA received, the rent paid minus 10% of salary, and 50% or 40% of salary.
Salary here means basic pay plus dearness allowance. The 50% places are Mumbai, Kolkata, Delhi, Chennai, Hyderabad, Pune, Ahmedabad and Bengaluru. Any other place is 40%.