You can claim the rebate if you satisfy both the following conditions:
You are a RESIDENT INDIVIDUAL; and
Your Total Income Less Deductions is equal to or less than Rs 3,50,000.
The rebate is limited to Rs 2,500. Which means if the total tax payable is lower than Rs 2,500, such lower amount of tax will be the rebate under section 87A. This rebate is applied on total tax before adding Education Cess(3%).