Glossary Background

All Or None Order

An all-or-none (AON) order is an instruction to execute a trade only if the full quantity can be filled, or else it’s canceled. For instance, if you order 1,000 shares with an AON condition, the trade won’t proceed if only 999 shares are available—it requires all 1,000. This ensures you get the exact amount desired, avoiding partial fills that might disrupt your strategy. Common in volatile or thinly traded markets, AON orders prioritize completeness over speed, but they risk not executing if supply falls short.