Partial fills on thin pairs and how they wreck position sizing
Posted: Sat Oct 31, 2026 6:33 am
A 5 lot order does not always fill as 5 lots. On exotic crosses and during off-hours, the order can come back as 2.3 lots, then 1.7, then the remainder at a worse price, and the trade ends up as three tickets with three different entries.
That matters for more than aesthetics. Stop distances calculated from the intended entry no longer line up with the actual average price, risk per trade drifts away from the plan, and managing three tickets by hand in a fast market is a recipe for mistakes.
Some platforms merge fills into one position, others show every fragment. Either way, the average entry is what counts, and checking it right after the fill is worth the second it takes.
Ways to reduce the problem include smaller clips, avoiding the first and last minutes of thin sessions, and sticking to pairs where the broker's depth is actually deep. Size that works fine on EURUSD can behave badly on NZDCAD.
Does anyone split orders deliberately to avoid partial fills, or does that just add more spread cost?
That matters for more than aesthetics. Stop distances calculated from the intended entry no longer line up with the actual average price, risk per trade drifts away from the plan, and managing three tickets by hand in a fast market is a recipe for mistakes.
Some platforms merge fills into one position, others show every fragment. Either way, the average entry is what counts, and checking it right after the fill is worth the second it takes.
Ways to reduce the problem include smaller clips, avoiding the first and last minutes of thin sessions, and sticking to pairs where the broker's depth is actually deep. Size that works fine on EURUSD can behave badly on NZDCAD.
Does anyone split orders deliberately to avoid partial fills, or does that just add more spread cost?