The £8.33 per month minimum charge is presently levied against anyone investing less than £20,000.
The company will also remove the annual £58.20 pension drawdown fee from the same date.
Old Mutual said the changes are designed to make is wealth offering better value for smaller investments and for customers looking to take advantage of the new pension withdrawal rules which take effect form April 2015.
“By removing our drawdown fee and the current minimum charge on the platform our customers will only pay one fee,” said Tom Hawkins, head of financial solutions.
“Additional layers of charges, such as those for switching, drawdown or exit charges are hazardous for customers as they can never fully predict future behaviour and therefore how much they will pay in the longer term,” he added.
“Following the Budget announcements, we believe drawdown charges should become obsolete,” Hawkins continued. “People will be given greater freedom as to how they access their pension savings and they will not expect to be charged extra for those freedoms. For providers, the new rules will remove much of the administration associated with income drawdown making an extra charge unnecessary.”