In financial markets, payment for order flow refers to the compensation that a broker receives, not from its client, but from a third party that wants to influence how the broker routes client orders for fulfillment. In general, market makers such as dealers and securities exchanges are willing to pay brokers for the right to fulfill small retail orders, since these can be matched more easily than large orders. The payment can be in the form of a direct cash incentive, a non-monetary service, or a reciprocal arrangement between broker-dealers to route particular order classes to each other. Market orders are typically preferred.
History
Payment for order flow was pioneered by Bernard Madoff. He described it as a way for market-makers to outsource the task of finding orders to fulfill, and compared it to retail arrangements in which a supplier pays for the rack on which its products are displayed. Although the practice was uninvolved in Madoff's later fraud scheme, it has long been controversial. The New York Stock Exchange opposed its use for years, but in February 2009 it sought permission from the U.S. Securities and Exchange Commission to adopt the practice on its electronic exchange. Payment for order flow has become less lucrative on a per share basis because of the decline in the tick size and the bid/ask spread. When stocks traded on 1/8ths of a dollar, payments for order flow were much larger than they became after 2001 when the tick size in U.S. markets fell to one cent. Larry Harris reported that in 1997, 24% of E-Trade's transaction revenue came from payment for order flow, but that by the second quarter of 2001 such payments accounted for only 15% of transaction revenue. A boom in payment for order flow was a key factor in the retail brokerage industry's move toward a zero-commission model in 2019, with startup Robinhood seeing an estimated threefold year-over-year increase in its routing revenue.
Analysis
The benign view is that in competitive markets, payment for order flow may allow smaller trading venues to compete more effectively with the NYSE. A more negative view is that exchanges and other market-makers who pay for order flow reduce liquidity on exchanges that do not pay for order flow and thus increase the bid–ask spread. This means that traders whose orders do not receive payment bear the cost to their detriment. Joel Seligman has noted that "Few practices are more likely to subvert quote competition" than payment for order flow. John C. Coffee has described it as a "bribe". He notes, however, that the SEC permits the practice because it sustained competitors to the NYSE and reduces the likelihood that NYSE specialists will obtain monopoly power.
Legality
In the United States, accepting payment for order flow is only allowed if no other trading venue is quoting a better price on the National Market System. Moreover, the broker must inform its client in writing that it accepts payment for order flow:
