An agent helps arrange the transaction
In a simple agency structure, the intermediary executes the client’s instruction by arranging a purchase from a third party. Its compensation may appear as a commission. But the agency label does not reveal every term: identify where the instruction is sent, how price is determined, which additional costs apply and how completion is confirmed. Good-faith execution cannot be established merely by the word “agent”. Nor should every commission be assumed to work the same way or to be independent of volume and other parameters.
In a principal structure, the organisation buys from or sells to the client out of its own position or through a connected sequence of trades. The SEC and FINRA explain that compensation may be included in the price through a markup or markdown.[37](#source-cm-confirm)[38](#source-cm-confirm-finra) No separately displayed commission therefore does not prove zero economic cost. A foreign educational example of compensation is not a universal disclosure rule on every market, and this guide does not reproduce historical SEC requirements as current law.
Compare the full money amount
A fictional agency purchase of twenty securities at 100 with a commission of 30 requires 2,030 monetary units. In another fictional trade, a dealer offers twenty securities at 101.50 with no separate commission; the total is also 2,030. Equal totals show only the arithmetic of these terms, not equal service quality, risk or rights. The second structure is not free, and the first is not necessarily more expensive merely because a commission line appears. The internal costs and profit cannot be reconstructed from the total without more data.
For a meaningful comparison, both transactions must concern the same security, quantity, time and execution terms. An indicative price cannot be compared with a confirmed price. Different settlement dates or currencies add further components. For bonds, accrued interest also matters. [Accrued interest](/guides/accrued-interest/) helps prevent treating a clean quote as the full cash amount. All figures are invented and are not current intermediary tariffs.
Role affects conflict-of-interest questions
If an organisation benefits from choosing a venue or is itself the opposite party, identify the relevant incentives and disclosures. That does not automatically establish a violation: a potential conflict and proven misconduct are different claims. But omitting the role is also wrong. The educational task is to ask a verifiable question about price, compensation and execution, not to assign motives without documents. Trading technology alone does not prove that a conflict is absent.
In the confirmation, check instrument, side, quantity, price, date, expenses and the participant’s role. FINRA recommends checking confirmations and resolving discrepancies with the firm.[38](#source-cm-confirm-finra) Complaint procedures and deadlines depend on applicable terms. If a report uses an unfamiliar code, clarify it rather than guessing from the company’s general name. Also distinguish a trading intermediary, clearing organisation and depositary participant; a common interface does not merge their obligations into one unconditional guarantee.
[Transaction flow](/guides/exchange-and-settlement/) connects instructions and settlement; [OTC counterparty risk](/guides/otc-counterparty-risk/) explains why the contractual party matters. This guide does not recommend a broker or dealer structure, assess a real organisation or establish current admission rules. Its result is a checkable distinction among role, price and compensation; “commission-free” is incomplete until total costs are known.
Checking the word “free”
Try to find the full amount the client pays or receives. If only a separate commission is shown, the comparison is unfinished. An embedded price difference, additional cost and execution condition may each matter. But an assumed markup cannot be estimated from an unsynchronised quote on another venue; a comparable reference is required.
A separate question is who is obligated to deliver the asset or money. An agency role in arranging a transaction is not identical to being the obligated counterparty. In a dispute, reconstruct the contractual chain rather than extending responsibility from a brand. The equal-total example does not establish equal legal protection or execution quality. The narrow conclusion is that no separate commission line does not prove zero costs.