time of supply

For supply of Goods
For the supply of goods advance received is not subject to GST. The entire amount will be taxed on the issue of the invoice (w.e.f. 15th November 2017).

For supply of service
if the advance is received before the issue of the invoice the time of supply would be the date of receipt of advance. 

As per Section 12 in case of advance or part payment is received then Time of Supply in case of supply of goods is restricted to the extent of advance received.

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