One can check the status of Income Tax refund from TIN-NSDL website. You can click on the below link:
Link to TIN-NSDL Refund Status Page
On visiting the above link, option as shown in image below:

On this page, you can provide your Permanent Account Number (PAN) and Assessment Year for which you want to check the status of income tax refund.
Assessment Year is the year in which you file the return of the Previous Year. For example, you file the return of your income for the period starting on 1st April 2016 and ending on 31st March 2017 in Assessment Year 2017-2018. Here 2016-2017 is the Previous Year, i.e. the year for which tax computations were done and 2017-2018 is the Assessment Year in which return for PY 2016-17 were filed/processed.
Refunds are issued via direct a/c transfer or paper check mode. Once the assessing officer has processed the return, status for the same can be checked after 10 days on which such assessing officer sends the refund. Refund sent shall also contain interest on tax refund. To know more about interest on tax, click the link below:
Learn about interest on Income tax refunds
You can also inquire about the refunds from the help-desk of SBI or through email at itro@sbi.co.in.