Q.Distinguish between the pre-GST and the post-GST indirect tax structure in India, naming at least three taxes that existed before GST and were subsumed by it.

GST's biggest structural change was replacing many separate Centre and State taxes with one unified tax.

Excise Duty, Service Tax, and State VAT/Sales Tax are three commonly cited subsumed taxes.

Before 1 July 2017, India's indirect tax structure was fragmented between the Centre and the States, each levying its own separate taxes:

This fragmentation caused a cascading 'tax on tax' effect, since a later tax (say, State VAT) was often charged on a value that already included an earlier tax (Excise Duty). GST subsumed nearly all of these separate levies into ONE unified tax, structured as CGST + SGST (or UTGST) for a supply within one State/Union Territory, and IGST for a supply between States or on import — with a single registration, return, and rate structure replacing the earlier patchwork. A small set of items (alcohol for human consumption, and currently five specified petroleum products) remain outside GST and continue under the old structure.

Naming Customs Duty on imports as a tax 'subsumed by GST' is imprecise — basic Customs Duty on imports still exists separately; it is the ADDITIONAL duties on imports (Countervailing Duty/Special Additional Duty, which effectively mirrored Excise/VAT) that were replaced by IGST on imports, not the basic Customs Duty itself.