With the deal done, Cetera now serves approximately 7,400 advisers with more than $141 billion in total client assets, the company said.
Tower Square and Walnut Street added approximately 800 advisers and more than $25 billion in assets, and expanded Cetera's footprint in the Midwest and Northeast, Cetera said.
The two firms will be folded into the largest Cetera broker-dealer, Cetera Advisor Networks LLC, which has more than 2,000 financial professionals. Cetera Advisor Networks operates regional supervisory offices, similar to Tower Square's and Walnut Street's structure.
Cetera has been one of the most active buyers of independent broker-dealers. Last year, it acquired Genworth Financial Investment Services Inc., later renamed Cetera Financial Specialists LLC.
Insurance companies such as MetLife are getting out of the independent-broker-dealer business because of the high risks, tight margins and falling profits from distributing variable annuities.
Cetera was formed in 2010 when private-equity firm Lightyear Capital LLC, run by former PaineWebber Group Inc. chairman and chief executive Donald Marron, bought three broker-dealers from Dutch insurer ING Groep NV.
The transaction with MetLife was announced last April. Terms of the deal were undisclosed.