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What is order flow in trading?

In one line: Order flow is the live stream of buy and sell orders hitting a market, and how aggressively buyers or sellers are taking the other side.

Trading glossary · Updated 2026-10-21

The short answer

A chart shows where price went. Order flow tries to show why: who was buying, who was selling, and who was in a hurry.

Traders read it with tools that show each trade as it happens, and whether it hit the bid or lifted the ask.

Who's aggressive?

Every trade has a buyer and a seller. One side is usually more eager.

• A buyer who pays the ask price is an aggressive buyer. They wanted in now.
• A seller who hits the bid price is an aggressive seller.
• Orders waiting in the book are passive. They let price come to them.

Order flow traders track which side is pushing. See Bid and ask.

A simple example

In one 5-minute candle on a futures contract:

• 1,800 contracts traded at the ask (aggressive buys)
• 1,200 contracts traded at the bid (aggressive sells)

The difference, 1,800 − 1,200 = +600, is often called delta. Positive delta means buyers were more aggressive in that candle. (This isn't the same as the options Delta.)

Now the twist. Say delta is +600 but price didn't rise. Aggressive buyers pushed and got nowhere. Someone large was selling to them passively. That's the kind of clue order flow traders look for. An illustration, not a signal.

The tools

• Tape reading: watching the time-and-sales list of every trade.
• Market depth / Level 2: the waiting orders above and below price.
• Footprint charts: candles that show buy and sell volume at every price.
• Volume profile: how much traded at each price over a period.

Why it matters

Order flow can add detail at a level you've already marked. It shows whether buyers really defend a floor or just poke at it.

It works best in markets with one central exchange, like futures. In spot forex there's no single order book, so true order flow data isn't available.

A common mistake

Starting with order flow. It's fast, noisy and easy to over-read. Without a clear level and a plan, it turns into staring at numbers.

Start with the chart: the trend and the places price turned. Then, if you want, use order flow to watch how price behaves at those places. Begin with how to read volume.

Questions