The deal is said to value Cowen at around $39 a share. The companies are expected to announce the deal this week, according to sources.
The acquisition is touted to help TD Bank further bolster its presence in the investment banking space and also in the US, where it has been expanding rapidly.
Apart from traditional investment banking, Cowen also provides investment research and management.
Last month, a report by Bloomberg News said that TD Bank was exploring a potential acquisition of the New York-headquartered brokerage firm.
The Toronto-headquartered lender has been rapidly growing its footprint through acquisitions.
In February, the firm agreed to takeover First Horizon Corp. in a deal worth $13.4bn. This acquisition is said to be the largest in the bank’s history.
It was also the first major deal under CEO Bharat Masrani who took the helm seven years ago. At the time, Masrani had signalled that the bank is eyeing more acquisitions.
Cowen is run by chair and CEO Jeffrey Solomon. Last year, the firm signed an agreement to purchase M&A advisory firm Portico Capital Advisors, which specialises in verticalised software, data, and analytics sector.
In 2017, Cowen snapped up Convergex Group, a trading services and brokerage firm, for $100.7m.