The bank had registered a net loss of Rs 346.02 crore during the corresponding October-December period of 2018-19.
Its total income during the December 2019 quarter also fell to Rs 5,197.94 crore from Rs 5,688.59 crore in the year-ago quarter, IOB said in a regulatory filing.
Provisioning for bad loans jumped to Rs 6,663.94 crore, compared with Rs 2,075.28 crore a year ago.
The bank's gross non-performing assets (NPAs), however, dropped to 17.12 per cent of the gross loans at the end of December 2019, from 23.76 per cent a year ago.
Net NPAs fell to 5.81 per cent from 13.56 per cent.
In value terms, the gross NPAs were valued at Rs 23,733.86 crore from Rs 35,786.57 crore. Net NPAs were Rs 7,087.09 crore from Rs 17,987.92 crore.
On NPA divergence for 2018-19, the bank said there was a gap of Rs 358 crore in gross bad loans, as the bank had reported it to be Rs 33,398 crore while the Reserve Bank of India assessed it to be at Rs 33,756 crore .
Net NPAs divergence was of Rs 358 crore and the divergence for provision came in at Rs 2,208 crore.
Thus, overall loss during 2018-19 was adjusted to Rs 5,999.90 crore from the earlier reported Rs 3,737.90 crore.
The provision coverage ratio improved to 86.20 per cent, IOB said.
Shares of IOB closed at Rs 9.92 apiece on the BSE, up 1.95 per cent. KPM HRS