The Australian Securities and Investments Commission says Commonwealth Financial Planning and BW Financial Advice could not prove they had advised about 31,500 customers between 2007 and 2015.
ASIC says CBA, which has also entered into an enforceable undertaking, has almost finished paying $88.6 million in compensation to customers.
In February, the bank — considered to be Australia’s largest and most profitable — posted a net profit of $4.91 billion for the six months of the financial year.
This new fine comes after it was revealed last year that the bank had breached mandatory reporting requirements on more than 53,000 potentially suspicious transactions.
Matt Comyn replaced the bank’s longstanding CEO, Ian Narev, earlier this month.