Professional tax is levied by individual states on salaried and professional income. The employer deducts it from salary and deposits it. It's modest - the constitutional cap is ₹2,500 per year - and rates/slabs vary by state. States without PT (e.g. some in the north) have no such deduction.
In India
Because it's state-specific, multi-state employers must run different PT slabs by work location - a common payroll-compliance detail that trips up new HR teams.
In practice
In Maharashtra, an employee earning above the top slab has ₹200/month deducted (₹300 in February to reach the ₹2,500 annual cap) - a small line on the payslip, but a compliance must-do for payroll.