When calculating Short-Term Capital Gains (STCG) and Long-Term Capital Gains (LTCG), several charges are incurred during security transactions. These include brokerage, exchange transaction charges, GST, SEBI fees, stamp duty, and DP charges. While most of these can be accounted for as expenditure, it's important to note that Securities Transaction Tax (STT) is generally not allowed as a deduction under sections 111A and 112A of the Income Tax Act.