All five brokers here charge $0 to trade stocks and ETFs online, and none of them are charities. The revenue moved; it did not disappear. Knowing where it went tells you more about which broker suits you than any star rating.
The biggest quiet earner is your cash. Brokers sweep uninvested cash into partner banks, earn a market rate on it, and pass on whatever they choose. As of early July 2026 the spread was stark: Schwab's default bank sweep paid 0.05% or less per 2026 reporting, E*TRADE's Bank Deposit Program paid 0.01% APY on typical balances, and Robinhood paid 0.01% without a Gold subscription, while Fidelity's default SPAXX sweep yielded 3.30% and Vanguard's VMFXX about 3.5%. On $10,000 of idle cash that is the difference between roughly $1 and roughly $340 a year, and it is why cash treatment gets its own column in our table. A one-off cash-sweep gap does more damage to real portfolios than a decade of the commission differences people used to argue about.
The second earner is payment for order flow: market-making firms pay brokers for routing customer orders to them, disclosed quarterly under SEC Rule 606. Robinhood receives PFOF on stock, ETF and options orders; Fidelity states it does not accept PFOF on retail US stock and ETF orders, though its own Rule 606 disclosures show it receives payment on options orders. PFOF is legal and disclosed, but the incentive is structural: a firm paid per trade benefits when you trade more, while boring index buying mostly benefits the person doing the buying.
The rest is a familiar list: options contract fees ($0.65 at Fidelity, Schwab and E*TRADE, $1 at Vanguard on accounts under $1 million), fund management fees, margin interest, and subscriptions like Robinhood Gold at $5/month. None of this makes any of these brokers bad. It makes them businesses, and the best defence is knowing which of their revenue lines you are personally feeding.