Definition
A Dealing Desk (DD) / B-Book model is an order execution approach where the broker acts as the counterparty to client trades. Instead of routing orders to external liquidity providers, the broker internalizes the order flow -- meaning the broker takes the opposite side of the client's trade. The broker's profit and loss is structurally linked to the client's trading outcome.
This is one of the most common execution models in retail FX, particularly among brokers targeting smaller account sizes. The broker effectively warehouses market risk, which it may hedge selectively with external LPs or manage on its own book. The term "B-Book" originates from the practice of keeping an internal book of client positions.
What It Is / What It Is Not
What Dealing Desk / B-Book IS
- Broker acts as counterparty to client orders
- Orders are internalized rather than routed to external LPs
- Broker warehouses market risk (full or partial)
- Enables fixed spreads and guaranteed fills in normal conditions
- Revenue comes from client losses, spread, and risk management
- May hedge aggregate exposure with external LPs selectively
What Dealing Desk / B-Book IS NOT
- Not inherently fraudulent or illegal -- it is a regulated business model
- Not automatically worse execution quality than A-Book
- Not the same as 'scam broker' -- many regulated entities use B-Book
- Not always zero hedging -- sophisticated B-Books hedge selectively
- Not exclusive to small brokers -- large institutions also internalize flow
- Not a guarantee of fixed spreads in all market conditions
Where It Appears in the Execution Stack
In a B-Book model, the execution stack is shorter because the order does not leave the broker's infrastructure for external execution:
Because the order stays within the broker, the dealing desk has full visibility and control over execution parameters. This enables faster fills but introduces potential for dealer intervention (requotes, delayed execution, asymmetric slippage).
Benefits & Trade-offs
| Factor | Detail | |
|---|---|---|
| Fill speed | Instant fills in normal conditions since no external routing needed | |
| Fixed spreads | Possible because the broker controls pricing, not external LPs | |
| Guaranteed execution | Broker can guarantee fills in normal conditions (not during extreme volatility) | |
| Conflict of interest | Structural conflict: broker profits when client loses, and vice versa | |
| Transparency | Execution decisions happen internally; difficult for client to verify routing | |
| Slippage symmetry | Risk of asymmetric slippage: negative slippage passed to client, positive retained | |
| Requotes | Dealer may requote orders during volatile periods or for profitable clients |
Common Marketing Claims vs Reality
| Claim | Reality |
|---|---|
| "Instant execution" | True in normal conditions, but requotes and dealer intervention may occur during volatility or for specific client profiles. |
| "We don't trade against you" | If the broker is the counterparty, it structurally does take the opposite side. The claim may refer to hedging practices, not the execution model itself. |
| "Tight fixed spreads" | Fixed spreads are a feature of B-Book control over pricing. They may widen or become unavailable during high-impact events. |
| "STP execution" | Some brokers label themselves "STP" while internalizing most flow. Verify whether orders actually reach external LPs. |
What to look for in an Execution Policy
- Does the execution policy state that the broker acts as counterparty?
- Is the proportion of internalized vs externally hedged flow disclosed?
- Are requote and rejection policies documented?
- Does the policy describe slippage handling (symmetric vs asymmetric)?
- Is there a conflict of interest disclosure section?
- Does the broker explain how it manages client-segment risk (e.g., profitable clients routed differently)?
See a Public Routing Disclosure Example
NDD.broker publishes detailed order routing and execution policy documentation, including LP composition, priority logic, and conflict mitigation. This serves as a reference implementation of the concepts described above.
Educational content only. This is not financial advice. Always consult qualified professionals before making trading decisions.