What a Brokerage Actually Does

The functions

Opening and maintaining the account — identity verification, suitability and eligibility checks, and the ongoing obligations that come with holding a customer relationship.

Accepting and routing orders — deciding where an instruction goes, which is covered mechanically in Pillar 29 — Orders and Execution and economically in Payment for Order Flow.

Clearing and settling — ensuring that money and securities actually change hands after a trade is agreed.

Custody — holding the assets, which is a separate function from everything above and is the subject of Custody: Who Actually Holds Your Assets.

Recordkeeping and reporting — statements, confirmations, cost basis, tax documents.

Processing corporate actions — dividends, splits, mergers, rights issues, and passing proxy materials to the beneficial owner, which is the plumbing behind Proxy Voting: How Shareholder Votes Work.

Lending — margin loans to customers, and lending customers' securities to other market participants.

Holding cash — uninvested balances, which sit somewhere and earn something.

The firm on the app is not always the firm holding the assets

Many retail brokers do not clear or custody anything. An introducing broker takes the customer relationship, accepts orders and passes them to a clearing broker that performs clearing, settlement, custody and often the statements. A self-clearing firm does both.

The consequence for a customer is that the entity whose name is on the application may not be the entity holding the securities, and the arrangement is disclosed rather than advertised. Which firm does what matters for custody, for protection schemes and for what happens if one of them fails — set out in Custody: Who Actually Holds Your Assets and Investor Protection Schemes and What They Cover.

How the money is made, including when the price is zero

This is the section that changes how the rest of the pillar reads.

The structural point, and it is a fact about the business model rather than a criticism of anyone. The revenue source a customer sees most clearly — the commission — can be set to zero while the firm remains profitable, because several of the largest sources are invisible at the point of use. Cash balances are the clearest case: a firm earns the difference between what it receives on customer cash and what it pays the customer on it, and that spread applies to every dollar sitting idle, continuously, whether or not the customer ever trades. Securities lending works similarly — the customer's holdings generate revenue for the firm, and depending on the arrangement the customer may receive part, all or none of it. None of this is hidden in the sense of being concealed: it appears in regulatory filings, account agreements and fee schedules. It is invisible in the narrower and more practical sense that it does not appear at the moment a decision is made. A reader who wants to know what an arrangement costs has to look at the disclosures rather than the headline price, and that is the whole of the point.

Why the model matters more than the price

How a firm is paid determines what it is structurally interested in. A firm earning from commissions has an interest in activity. A firm earning from cash balances has an interest in balances. A firm earning from margin lending has an interest in borrowing. A firm earning a percentage of assets has an interest in assets remaining with it.

None of those interests is improper and all of them are ordinary. The reason to understand them is not suspicion — it is that a service is shaped by what pays for it, and knowing which revenue line a feature serves explains a great deal that the marketing does not.