Who Are the Best Small Online Brokers? Brokerage start-ups such as Robinhood, M1 Finance and SoFi are tiny compared with the trillions of dollars in brokerage assets at the likes of Schwab and Fidelity. But they’ve already made a big dent in the way things work: These newcomers pioneered commission-free stock trading and fractional-share purchases, and now those services are standard fare at the big online brokers. The smaller firms don’t qualify for our annual online broker review because they don’t offer mutual fund or bond trading. But we put five firms—Betterment, M1 Finance, moomoo, Robinhood and SoFi—through the paces of a trimmer survey this year. For the record, Webull didn’t respond to our invitations; tastyworks declined. The overall winner is Robinhood. It dominated two key categories, mobile and investment choices. SoFi also scored well, posting above-average scores in all but one category, tools and research. M1 Finance finished third with high marks in tools and research, user experience, and investment choices.