Fills that depend on the order of arrival

[Fairman]

Fills that depend on the order of arrival

Two traders place orders at the same instant on the same broker. One fills at 1.0850, the other at 1.0851. Same pair, same size.

The difference is order of arrival and how the broker's server processes the queue. Priority can depend on connection quality, account type, or even internal rules.

Some brokers give priority to certain account tiers. Others process strictly by timestamp. The details are rarely published.

For scalpers, small differences accumulate. Being one place behind in a queue for a thousand trades is a cost.

Testing the idea is difficult without a second account. Running the same orders from two accounts at the same time and comparing fills shows whether there is a systematic difference.

A cheap indicator of fairness is the spread of fill delays over many orders. If identical orders sent minutes apart show wildly different times to fill, something in the queue is variable, whether load, priority rules or routing. A tight distribution suggests a consistent process. A ragged one deserves a question to the broker's support team.

Is any difference visible between fills on two accounts at the same broker, placed together?

[FXS HongKong Scalper]

Fills that depend on the order of arrival Two traders place orders at the same instant on the same broker.

Order of arrival matters more than most people think. For a manual trader, the practical takeaway is that a one pip difference between two traders' fills is not necessarily a sign of manipulation. It becomes one only if the difference is consistently in one direction for one account type, which needs a log of many fills to show.