A-Book vs B-Book Broker

A-Book brokers pass client orders to external liquidity providers, while B-Book brokers take the other side of client trades internally. The model affects spreads, execution, and IB economics.

What it means in practice

The A-Book and B-Book labels describe how a forex broker handles client orders internally. An A-Book broker routes client trades to external liquidity providers -- acting as an intermediary that earns from commissions and spread markup. A B-Book broker internalizes client orders, taking the opposite side of each trade. Most retail brokers operate a hybrid model, A-Booking large or profitable clients while B-Booking smaller or less experienced traders.

This distinction matters for introducing brokers and affiliate partners because it directly affects commission economics. B-Book brokers retain more revenue per trade (since they capture the full spread plus potential client losses), which allows them to offer higher IB rebates and more flexible spread-based commission arrangements. A-Book brokers operate on thinner margins but offer a more transparent, conflict-free model that can be easier to market to sophisticated traders.

From a regulatory perspective, both models are legitimate when properly managed. However, B-Book brokers face greater scrutiny in jurisdictions with strict conduct-of-business rules, particularly around order execution quality and conflict-of-interest management. IBs evaluating broker partnerships should understand how the broker manages its book, as this affects both the sustainability of the IB's commission stream and the broker's reputation in the market.

A-Book (STP/ECN) vs B-Book (Market Maker)

Side-by-side breakdown of how these two models compare across key dimensions.

Dimension
A-Book (STP/ECN)
B-Book (Market Maker)
Order execution
Orders routed to external liquidity providers
Orders filled internally by the broker
Broker revenue source
Commission per trade and/or spread markup
Spread and net result of client positions
Conflict of interest
Minimal -- broker profits from volume, not client losses
Inherent -- broker profits when client loses
Spread type
Variable, market-driven
Often fixed or semi-fixed
Minimum deposit
Typically higher
Often lower, accessible for beginners
IB commission flexibility
Limited -- broker margins are thinner
Higher -- broker retains more revenue per trade
Execution speed
May have slight latency due to external routing
Typically instant fill with no requotes
A-Book (STP/ECN)

Advantages

  • No conflict of interest between broker and client
  • Market-driven pricing with transparent execution
  • Attractive to experienced and institutional traders
  • Better alignment with long-term client retention

Limitations

  • Thinner margins limit IB commission flexibility
  • Variable spreads can widen during volatile markets
  • Higher minimum deposits may reduce IB client volume
B-Book (Market Maker)

Advantages

  • Higher margins enable more competitive IB rebates
  • Fixed spreads and lower minimums attract beginners
  • Instant execution with no external routing latency
  • Flexible pricing and promotional capability

Limitations

  • Inherent conflict of interest with client positions
  • Regulatory scrutiny in some jurisdictions
  • Reputation risk if perceived as trading against clients

When to choose which

Choose A-Book (STP/ECN)

A-Book brokers are preferred by introducing brokers who prioritize long-term client relationships and whose clients are experienced traders sensitive to execution quality. The A-Book model aligns IB incentives with client success because IB commissions grow with trading volume, and successful traders trade more. IBs working with A-Book brokers typically earn lot-based commissions.

Choose B-Book (Market Maker)

B-Book brokers suit IBs focused on high-volume client acquisition, particularly in markets with many beginner traders. The higher margins available in the B-Book model allow brokers to offer more attractive IB rebate structures and lower barriers to entry. However, IBs should evaluate the broker's risk management practices and regulatory standing.

How A-Book vs B-Book Broker works across industries

See how a-book vs b-book broker is applied in the verticals Track360 supports, from qualification logic and payout structure to the operational context behind each model.

Forex

A-Book vs B-Book Broker in Forex partner and IB models

Most retail forex brokers operate a hybrid A-Book/B-Book model, routing different client segments differently based on profitability profile. IBs often don't know exactly how their referred clients are booked, but the broker's overall execution model affects the commission structures available. IBs working with predominantly B-Book brokers should understand that their commission economics depend on the broker's ability to manage the risk of internalizing client flow.
Read More

How Track360 handles this

Track360 supports commission tracking across both A-Book and B-Book broker models, handling lot-based, spread-based, and hybrid commission structures. Operators can configure separate commission tiers and reporting for different IB segments regardless of their execution model.

FAQ

Frequently Asked Questions

Common questions about a-book vs b-book broker, how it works in affiliate programs, and where it shows up across Track360's supported verticals.

An A-Book broker routes client orders to external liquidity providers, earning from commissions and spread markup. A B-Book broker fills orders internally by taking the opposite side of client trades, profiting from the spread and from client losses. Most brokers use a hybrid approach, booking different clients differently.

Related Terms

Forex & IB

ECN Broker

Forex
Read Definition

An ECN broker routes client orders directly to liquidity providers via an electronic communication network, offering variable spreads and transparent pricing.

Forex & IBRead More β†’
Forex & IB

STP Broker (Straight Through Processing)

Forex
Read Definition

An STP broker routes client orders directly to liquidity providers without a dealing desk, earning revenue through spread markups or commissions.

Forex & IBRead More β†’
Forex & IB

STP vs ECN Broker

Forex
Read Definition

STP brokers route orders to liquidity providers with a spread markup. ECN brokers provide direct order book access with per-trade commissions.

Forex & IBRead More β†’
Forex & IB

Market Maker Broker

Forex
Read Definition

A market maker broker acts as the counterparty to client trades, setting its own bid/ask prices rather than routing orders directly to the interbank market.

Forex & IBRead More β†’
Forex & IB

Introducing Broker (IB)

Forex
Read Definition

An Introducing Broker is a partner who refers new traders to a Forex or CFD brokerage in exchange for ongoing commissions, typically calculated on the trading volume or revenue generated by those referred clients.

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Forex & IB

IB Rebate

Forex
Read Definition

An IB rebate is a payment that an introducing broker passes back to referred clients, typically funded from the IB's own commission share. Rebates are used to attract and retain active traders by reducing their effective trading costs.

Forex & IBRead More β†’
Forex & IB

Spread

Forex
Read Definition

The spread is the difference between the bid (sell) and ask (buy) price of a financial instrument, serving as a primary revenue source for Forex brokers and a basis for spread-based affiliate commissions.

Forex & IBRead More β†’
Forex & IB

Liquidity Provider

ForexProp Trading
Read Definition

A liquidity provider is a financial institution or entity that supplies buy and sell quotes to brokers, enabling trade execution at competitive spreads.

Forex & IBRead More β†’
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