forex-scalping.com

The spread is a thermometer for the liquidity providers

When the spread changes, it reflects the behaviour of the liquidity providers behind the price. A sudden widening often comes before the visible move in price.

A rising spread with a still price suggests providers are stepping back, anticipating something. It could be an upcoming news event, or an unusual flow that they are trying to avoid.

For scalpers, monitoring the spread tick by tick can offer a few seconds of warning. If the spread doubles without an obvious reason, caution is justified. Entering at that moment is expensive and the market is likely about to move.

Conversely, a tightening spread during a quiet period can signal returning liquidity, a good time to scale up activity.

An on-screen spread display, or a simple indicator that colours when the spread exceeds a threshold, makes the information visible. Many platforms hide it by default.

It requires no special data. The spread is already there in every tick.

Has a sudden widening of the spread ever preceded a move, and how much notice did it give?

The price on a retail platform has passed through several steps. Between the liquidity providers and the trading terminal sits a bridge or aggregator: software that collects quotes from multiple sources, combines them, applies the broker's markup, and routes orders.

The quality of that software varies. A good aggregator creates a tight composite price, handles rejections gracefully, and routes orders quickly. A weak one introduces latency, creates stale quotes, and produces odd fills.

Some effects of the aggregator's logic are visible. When the best bid comes from provider A and the best ask from provider B, the spread is tight. An order to buy goes to B at the ask. If B's price has changed, the order may be rejected and retried elsewhere, adding delay.

Markups are another factor. The broker adds a fixed or variable amount to the aggregated spread. This can be adjusted by account type, time of day, or volatility.

None of it is visible to the client. What is visible is behavior: spread stability, rejection rate, and fill timing.

Do the broker's spreads during stress suggest a solid liquidity setup or a thin one?