To begin with the individual can visit https://tin.tin.nsdl.com/oltas/refundstatuslogin.html
Thereafter, one can enter the assessment year and the PAN number. On doing so, he or she can view the status of his refund.
If the refund has not yet been issued it would read: "Your assessing officer has not sent this refund to Refund Banker." This means that your refund has not been completed as yet.
The 'Refund Banker Scheme,' was initiated in 2007, and is operational for non-corporate taxpayers from Mumbai, Delhi, Kolkata, Chennai, Bangalore, Bhubaneswar, Ahmedabad, Hyderabad, Pune, Patna, Cochin, Trivandrum, Chandigarh, Allahabad, and Kanpur.
Under the 'Refund Banker Scheme' refunds are generated on processing of Income Tax Returns by the Assessing officers/CPC-Bangalore. They are then transmitted to State Bank of India, CMP branch, Mumbai (Refund Banker) on the next day of processing for further distribution to taxpayers.
Refunds are sent by the IT authorities in following two ways:
i. RTGS / NECS: To enable credit of refund directly to the bank account, Taxpayer's Bank A/c (at least 10 digits), MICR code of bank branch and correct communication address is mandatory.
ii. Paper Cheque: Bank Account No, Correct address is mandatory.
Taxpayers can view status of refund 10 days after their refund has been sent by the Assessing Officer to the Refund Banker - by entering 'PAN' and 'Assessment Year' below.
In case your refund has not been processed you can contact the assessing officer who than would look into the matter. Make sure that you have entered the correct bank details at the time of filing returns and your correct postal address.
Also read on How to file complaint for delay in income tax returns here