A liquidity provider (LP) is a bank or non-bank market maker that streams prices to brokers. The quality and number of LPs behind a broker affect spreads and fills more than most account features.
Types of LPs:
Large banks with FX dealing desks.
Non-bank electronic market makers.
Aggregators that combine multiple sources into one stream.
Why it matters for traders:
More LPs can mean tighter spreads and better fills, because the broker can pick the best price at each moment.
During news, LPs may widen or stop quoting, which is exactly when the difference between brokers becomes visible.
Some LPs use last look, which can lead to rejected orders.
Some brokers name their LPs; others only describe them generally ("tier-1 banks"). Execution data you collect yourself tells you more than the list.
Do you know which liquidity providers your broker uses, and does it influence your choice?
FXS Prop Desk wrote: Thu Oct 08, 2026 9:32 pm
A liquidity provider (LP) is a bank or non-bank market maker that streams prices to brokers. The quality and number of LPs behind a broker affect spreads and fills more than most account features.
Types of LPs:
Large banks with FX dealing desks.
Non-bank electronic market makers.
Aggregators that combine multiple sources into one stream.
Why it matters for traders:
More LPs can mean tighter spreads and better fills, because the broker can pick the best price at each moment.
During news, LPs may widen or stop quoting, which is exactly when the difference between brokers becomes visible.
Some LPs use last look, which can lead to rejected orders.
Some brokers name their LPs; others only describe them generally ("tier-1 banks"). Execution data you collect yourself tells you more than the list.
Do you know which liquidity providers your broker uses, and does it influence your choice?
Hello FXS Prop Desk,
The specific names of a broker's liquidity providers matter less than the empirical execution data gathered from the trade server, but the underlying LP architecture fundamentally dictates where trading capital should be deployed. While broker marketing materials frequently tout "Tier-1 bank" aggregation, the actual market microstructure—how that liquidity is routed, matched, and maintained during volatility—is what separates a viable execution environment from a toxic one.
Here is an extended breakdown of why LP architecture heavily influences broker selection and how it impacts live execution:
The Problem with "Last Look" Pricing
Many traditional Tier-1 banks utilize "last look" execution, giving them a brief window (often milliseconds) to reject an order if the price moves against them before fulfillment. When trading raw price action or executing rapid setups around critical liquidity sweeps, this results in asymmetrical slippage and high rejection rates. Brokers that route heavily to non-bank electronic market makers often provide "no last look" pricing, which is vastly superior for automated execution scripts and strict price action models where certainty of fill is paramount.
A deep pool of aggregated LPs looks excellent during quiet market hours, but the true test of a broker's feed is its behavior during macroeconomic news or sudden liquidity voids.
Bank LPs typically widen spreads defensively but often keep the order book open.
Non-bank aggregators might offer tighter top-of-book pricing normally, but their liquidity can evaporate entirely during high-impact events, leaving the book hollow.
When your edge relies on mapping structural levels on daily or 15-minute charts, sudden spread widening can trigger stops prematurely, ruining a perfectly valid technical setup simply because the broker's LP pool temporarily drained.
Because broker claims about their liquidity pool are opaque, the choice of broker must be dictated by custom order rejection logging and execution telemetry gathered directly from the platform (whether through MQL4/5, cAlgo, or Pine Script integrations).
Latency mapping: Tracking the exact millisecond delay between the order send and the server's fill confirmation.
Data fidelity: Ensuring the aggregated feed doesn't create artificial price spikes or ghost prints that distort candlestick structures.
Slippage symmetry: Logging whether positive slippage is passed on to the account as frequently as negative slippage.
Ultimately, the choice of broker is heavily influenced by the behavior of their LPs rather than their names. The only way to know if an aggregator is actually fighting for the best price is to measure spread stability and fill times during both peak volume and violent market sweeps.
What specific telemetry metrics are you currently prioritizing when logging your own trade execution quality?
FXS Prop Desk wrote: Some LPs use last look, which can lead to rejected orders.
On last look, two details are worth asking a broker about, because they matter more than whether it exists at all. The hold time, meaning how long the LP can wait before accepting or rejecting, which can be a few milliseconds or a lot longer. And symmetry, meaning whether the price check only rejects trades that moved against the LP, or also gives you the improvement when the market moved in your favour during the window. Asymmetric last look is the version that costs a scalper. The FX Global Code, which most of the big bank and non-bank LPs have signed up to, expects them to disclose how they use last look, so a broker that takes execution seriously should be able to say what its LPs do. A reject log by time of day remains the practical test.
