Morgan Stanley is buying E*Trade Financial in a $13bn deal that will reshape the storied investment bank and firmly stake its future on managing money for regular people.

The all-stock takeover, set to be announced Thursday, will combine a Wall Street firm in the late innings of a decadelong turnaround with a discount broker built on the backs of dot-com day traders. It is the biggest takeover by a giant US bank since the 2008 crisis.