A total of 137,880 people, or 22,980 families, have left their homes since the start of the operation on October 17, the IOM said.
The figure includes almost 135,000 who have been displaced in the Nineveh province, of which Mosul is the capital, while a total of 43,728 having fled the city itself.
In a previous report on Friday, which was released shortly after the Iraqi offensive resumed following a two-week pause, IOM figures stood at just over 133,000 displaced.
Some 70,000 people remain trapped in ISIL-held western district of Mosul, while three quarters of those displaced being sheltered in emergency sites operated by the government, the United Nations, the IOM and other humanitarian organizations, according to IOM.
The operation to liberate Mosul, in the northern Iraqi province of Nineveh, from ISIL began on October 17, 2016. Iraqi troops have made advances in the eastern part of the city, but the right bank of the Tigris River remains under militant control. On Sunday, the Iraqi army reportedly reached the eastern bank of the river overlooking ISIL positions on the opposite side of the river.
The operation began with 4,000 Peshmerga fighters and 30,000 Iraqi soldiers backed by the US-led coalition.
SPUTNIK/MNA