Scenarios in which you can apply for GST refund :

1) Excess Balance available in Electronic Cash Ledger
2) Export of Goods & Services ( Tax paid )
3) Export of Goods & Services ( Tax not paid )
4) Refund due to appeal assessment or provisional assessment
5) Excess Payment of Tax
6) Tax paid under CGST and SGST which is subsequently considered IGST or vice-versa
7) Supplies made to SEZ unit and SEZ Developer
8) Accumulated ITC due to excess tax paid on inputs than outward supplies

Timeline for filing for GST refund :

The refund claim has to be made within two years from the relevant date in RFD-01/ RFD-01A.
The RFD-01A has to be filed on monthly basis for the following cases:
1. Refund claims in case of Zero-rated supplies
2. Refund claims in case of Inverted Duty Structure
3. Refund claims in case of Deemed Exports
4. Refund of excess balance in Electronic Cash ledger
RFD-01A can be filed Quarterly instead of Monthly only in case where the taxpayer has turnover below Rs. 1.5 crores and has opted to file Quarterly returns.
In case of supply of goods to SEZ units or SEZ developer, a supplier has to file this form once the receipt of goods is confirmed by an authentication from the specified officer of that zone.
In case of supply of services to SEZ units or SEZ developer, a supplier has to file this form once the evidence of receipt of service is confirmed by authentication from the specified officer of that zone.