According to Income Tax rules, with effect from Assessment Year 2017-18, benefit of concessional tax rate of 15% (in case of Short Term Capital Gains (STCG)) shall be available even where Securities Transaction Tax (STT) is not paid. But the following conditions need to be met - transaction should be undertaken on a recognised stock exchange located in any International Financial Service Centre, and ‐ consideration is paid or payable in foreign currency. If these conditions are not met, your STCG will be taxed as per your tax slab. Also, note that Long Term Capital Gains (LTCG) in case STT is not paid, is only 10% with indexation. 20% without indexation is not available.