CST full form means Central Standard Time and stands behind 6 hours behind Coordinated Universal Time. It is mainly observed in the regions of Central and North America. CST stands for Central Sales Tax. It is a tax imposed by the Central Government of India on the sale of goods and services between different states. This tax does not apply to imports, exports, or sales within one state. It must be paid in the form where the goods or services are sold. COMMERCIAL TAXES DEPARTMENT ... CST Forms CST Full Form CST is denoted to Central State Tax, which is the expense one needs to pay on the offer of merchandise that is sold through between state exchanges. Central State Tax charge alludes to the assessment demanded on deals created between state exchange and business in a country.