A ₹1,44,000 raise, and a bonus that doesn't move
Starting from a ₹12,00,000 annual salary at 50% basic pay (₹50,000 monthly basic, or ₹6,00,000 annually), a 12% increment raises the total salary to ₹13,44,000 — and at the same 50% basic policy, monthly basic rises to ₹56,000 (₹6,72,000 annually). Yet the statutory bonus, at the minimum 8.33% rate, is ₹6,997.20 both before and after the raise — not a rupee of difference.
Why the bonus doesn't move
The Payment of Bonus Act caps the wage used for bonus calculation at ₹7,000 a month, regardless of actual basic salary. Both ₹50,000 and ₹56,000 a month are already far above that ₹7,000 ceiling, so both scenarios use the exact same capped ₹7,000 figure to compute the bonus — the raise never touches the number that actually determines it.
When a raise would change the bonus
For someone whose basic salary starts below the ₹7,000/month ceiling — say ₹5,000 a month (₹60,000 a year) — the bonus is calculated on the actual ₹5,000 figure, giving ₹4,998 at the 8.33% rate. A raise that pushes basic pay up (but still below ₹7,000) would genuinely increase this bonus, since the ceiling isn't yet binding.
The general pattern
Once any input to a calculation is capped, further increases to that input stop affecting the result — a raise only changes statutory bonus for employees whose basic salary currently sits below the ₹7,000/month threshold; above it, the bonus is effectively fixed regardless of how large future raises are.