What happens if I Choose “post only”?

If you choose the option “Post only”, your order will only ever be a maker. It will never match with any orders already on the book and will wait for a taker to match with it.

What is a taker order?

1.61 (Taker Order) If an Order is posted to the Order Book at the same price as one or more existing Orders, it is a Taker Order which will result in an immediate Fill at that price, to the extent of the total quantity of those existing Orders.

Can a 'post only' order be placed during an auction?

‘Post only’ orders cannot be placed during an Auction. 1.34 A Limit Order without ‘post-only’ selected will be immediately posted to the Order Book (subject to any Time in Force Instructions) and can result in a Maker Order or a Taker Order, or an Order that is partially a Maker Order and partially a Taker Order.

What happens if a post only order matches an existing order?

If a post only order will partially or fully match against an existing order in the order book, then the post only order is cancelled. How to make an order post only?