Order Blocks Explained: Supply & Demand by Another Name

This is the third page in a little series I didn't plan. After writing about the fair value gap and the liquidity sweep, the question I got most was "what about order blocks?"

Same honest answer. I don't trade order blocks, and I don't draw them on my charts. But I do pay close attention to the areas they point at, because they're supply and demand zones, and supply and demand is how I think about every level. So this page explains what an order block is, why it's the same idea, and how I actually read these zones.

What Is an Order Block?

An order block is the last candle in the opposite direction before a strong, impulsive move:

• Bullish order block: the last down candle before a sharp rally.
• Bearish order block: the last up candle before a sharp drop.

The reasoning behind it is that large traders can't fill a big position in one go. They build it in an area, and once they're done, price leaves fast. If part of their order is still unfilled, or if they want to defend their position, they'll step in again when price comes back to that area. So the order block is where you'd expect the same side to show up again.

Most definitions also want the move to break structure, so a bullish order block only counts if the rally that followed made a new high.

The Honest Part: It's Supply and Demand

Long before anyone said "order block", traders were marking the same areas as supply and demand zones. A demand zone is the base price rallied away from, often taught as "drop, base, rally". A bullish order block is simply the last candle of that base. The order block is drawn tighter, the zone a bit wider, but they're pointing at the same place for the same reason.

And if you look at it from an auction point of view, which is how I read markets, it's the spot where one side took initiative and the market left in a hurry. On a market profile that move usually leaves single prints. On a candle chart it often leaves a fair value gap right above the order block. Same event, seen through different tools:

I'm not saying this to knock anyone who learned it as an order block. It's useful to see the whole picture, because the order block on its own is the weakest part of it. Any pullback candle before a move qualifies. What makes the area worth trading is everything around it.

Break of Structure and Change of Character

Break of structure (BOS) means price takes out the previous swing high in an uptrend, or the previous swing low in a downtrend. In plain words, the trend made another higher high or lower low.

Change of character (CHoCH) is the first break the other way. In an uptrend, the first time price breaks below the last higher low, the trend might be turning.

This is the oldest definition of a trend there is. Dow Theory described trends as a series of higher highs and higher lows more than a hundred years ago. The new names are fine, and they make the idea easy to talk about. Just don't treat a break of structure as a signal on its own. Every trend day breaks structure all day, and every range day "breaks structure" back and forth until it doesn't.

Where BOS is useful is as a filter. If structure is clearly up, I only care about long setups at support. If it's clearly down, only shorts at resistance. If it's chopping both ways, the market is balancing, and I trade the edges of the range instead.

How I Read These Zones: Supply and Demand

I don't mark the last candle before a move. I ask a simpler question: where did buyers or sellers clearly win, and are they still there when price comes back? Here's what I check, in order:

1. The zone started a real move

The move away from the zone should be fast and obvious, ideally leaving a fair value gap or single prints behind it. A slow grind away from a candle isn't an order block worth caring about.

2. The zone sits at a real level

A demand zone that sits on the prior day's low, the overnight low, VWAP or a value area edge is far more interesting than one floating in the middle of nowhere. The level is what gets other traders to act there too.

3. I wait for the defense

When price comes back into the zone, don't buy just because it touched it. Open the footprint and watch. If the buyers who started the move are still there, you'll see sellers hit the bid and get absorbed, then price move away from the zone for the first time. That's the entry, with the stop beyond the zone. If sellers keep pushing through it, the zone is done, and that's information too.

4. The trend filter

Demand zones in an uptrend, supply zones in a downtrend. Counter-trend zones are where most of the losses in this style come from, whatever you call them.

Mistakes I See With Order Blocks and Zones

• Marking every candle. If your chart has twenty order blocks on it, none of them mean anything.
• Trading the first touch blind. A zone is a place to watch, not a reason to enter.
• Timeframe shopping. Every timeframe has order blocks. If you keep zooming until one agrees with your bias, the pattern isn't doing the work.
• Ignoring the day type. On a strong trend day, counter-trend zones get run over one after another.
• Stops inside the zone. If the zone is your reason for the trade, your stop belongs beyond it, sized with proper risk management.

Order Block FAQ

What is an order block in trading?

The last opposite candle before a strong move. A bullish order block is the last down candle before a sharp rally, a bearish one is the last up candle before a sharp drop. The idea is that the side that started the move may defend that area when price returns.

Is an order block the same as a supply and demand zone?

Same idea. The demand zone is the whole base price rallied from, and the order block is the last candle of that base. Order blocks are drawn tighter, zones wider.

What is the difference between an order block and a fair value gap?

The order block is where the move started. The fair value gap is the area the move ran through too fast to trade properly. They often sit right next to each other.

What is a break of structure?

Price breaking the previous swing high in an uptrend, or swing low in a downtrend, which is another way of saying the trend made a new higher high or lower low. A change of character is the first break the other way.

Do order blocks actually work?

Sometimes, like every pattern. Most candles that qualify never produce a reaction. They work best at a real level, with the side that started the move visibly defending the zone on the retest.

How do you trade an order block or supply and demand zone?

As a location, not a signal. Pick zones that started a clear move and sit at a real level, wait for the defense when price returns, and put your stop beyond the zone.