After surging 8.71 per cent to Rs 139.15 in intra-day trade, IDFC's stock surrendered the gains and ended at Rs 124.95, down 2.38 per cent at the BSE.
On the NSE, the company's stock settled lower by 2.43 per cent at Rs 124.70.
The Reserve Bank had yesterday granted an in-principle approval to IDFC and Bandhan Financial Services to foray into the banking business.
On being satisfied that the applicants have complied with the requisite conditions laid down by the RBI as part of in-principle approval, they would be considered for grant of a licence for commencement of banking business, it said.
Until a regular licence is issued, the applicants would be barred from doing banking business.
In the broader market, the BSE benchmark Sensex ended at 22,509.07, down 42.42 points.