Last October, Citigroup agreed to return a total of $16 million to nearly 30,000 customers after an investigation by the state of New York found the company overcharged some customers advisory fees on their investment accounts. While that redress seems pretty hefty, it wasn’t enough, with the financial institution now agreeing to pay an additional $4.5 million to another 15,000 account holders.

New York Attorney General Eric Schneiderman announced the new agreement on Wednesday, after an internal investigation by Citigroup’s subsidiary Citi Global Markets Inc. (CGMI) found additional overcharges on customer accounts.

According to the review, for certain types of investment accounts CGMI charged fees for account management prospectively; meaning fees were assessed at the beginning of a quarter to cover the upcoming months.

While this is a common practice for many companies, the investigation found that CGMI assessed the advisory fees to customer accounts that were frozen or otherwise inactive and should not have been charged.

In some cases, if a customer requested a refund of prospectively paid fees that covered a period when the customer’s account was frozen, CGMI would issue a rebate.

However, in other instances, thousands of customers who were overcharged fees during frozen periods were not allocated rebates they should have received, either because they did not request a rebate, or because CGMI did not have policies and procedures in place to determine when rebates were appropriate, according to the attorney general’s office.

As a result, a total of 46,000 customers were charged more than $20 million in fees by CGMI.

Today’s refunds come as a result of an agreement made between the bank and the state attorney general last October.

That case was based on an investigation into CGMI’s fees that started in 2012 after the AG’s office received a complaint from a resident who had negotiated a fee with the company but was overcharged for a period of three years.

Following the investigation, the New York Attorney General’s office announced some 30,000 customers would receive $16.4 million in refunds for the same overcharging practice by Citigroup’s subsidiary.

As part of that settlement, CGMI agreed to conduct an internal review of other accounts to determine if there were other overcharges related to inactive accounts, which led to the discovery of the additional 15,000 overcharged accounts.

A.G. Schneiderman Announces Return Of Additional $4.5 Million To 15,000 Citi Customers For Fee Overcharges [New York Attorney General’s Office]

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.