Money stops: deciding the exit while you're calm

After this lesson you can set a money stop before entering any trade, and you'll know why moving it afterward breaks everything built so far.

A decision with a deadline

Every course so far has leaned on one assumption: that you know, before you buy, the price at which you'll sell at a loss. That decision has a deadline, and the deadline is the moment you enter. Push it past the entry and you'll end up making it while losing money, which is about the worst documented condition for human judgment. School VII spends a whole course on what an open loss does to decision-making; this course just makes sure you never have to find out personally.

A money stop is the plainest version of the pre-decided exit: the price at which your loss equals the amount you agreed to pay to find out whether the trade works. You know R (course 2) and you know your size (course 3), so the stop follows by division. Fifty shares with R = €100 means €2 per share, so a €40 entry puts the money stop at €38.

Later, in Schools III and V, stops get smarter: they move to prices where the trade's actual reason has failed, such as a support level or a volatility distance. The money stop is the beginner version, and it already puts you ahead of most of the market, since most of the market enters with no exit decision at all.

The contract

This school is called Risk First: the Contract, and the stop is the contract. You, calm, before the trade: if it trades at €38, I was wrong, I pay €100, I move on. Everything this school has built assumes the loss actually stays at 1R when it comes. Two behaviours break it, and both are common enough to deserve their own paragraphs.

Widening the stop. Price falls to €38.20 and it suddenly seems reasonable to move the stop from €38 down to €36, "to give the trade room." The reasoning behind the trade is the same as it was an hour ago. You're €90 down, and the stop is about to do the job it was placed there for. Move it and the planned €100 loss becomes €200; do it twice and course 1's table starts to matter. Traders who do this carry journals full of −2R and −4R lines and can't work out why a decent win rate leaves the account flat. Course 4 can tell them: the average loss quietly doubled, and expectancy went with it.

Averaging down. Buy 100 shares at €40, watch it drop to €36, buy 100 more because "now my breakeven is only €38." True, and now every further euro of drop costs double, in a stock that has been going against you from the start, with the original stop long abandoned. One planned 1R loss turns into a much bigger one, with extra size behind it.

We once built the first of those two behaviours into software, which is the best evidence we can offer for how reasonable it feels from the inside. The desk's backtester carried a feature that widened a stop on days when trading costs looked high, on the reasoning that an expensive, noisy session shouldn't stop you out on noise. It read as prudence in review. When we finally audited what it did rather than what it intended, it had rewritten 99.5% of the stops in the test, and every number downstream of it described a system nobody had designed. We deleted it, which is also why the Arena has no widen control anywhere in its interface. A rule that widened stops looked sensible enough here to survive a code review, so the version of it that arrives in your head at €38.20 will be at least as persuasive.

Where the stop lives

A practical note that saves accounts: the stop should exist as a working order at your broker, entered right after the entry fills. (Order mechanics are School I, course 10. For a protective stop you want the stop-market type, because when you're wrong you want out at the market's price.) A stop that exists only in your head has to be re-decided in the exact moment you're least equipped to decide it. An order sitting at the broker just executes, and it does that while you're at work or asleep.

One honest caveat belongs next to that: there is a situation where even a working stop can't hold the loss to 1R, and that's what the next course is about.

Check yourself

1. R = €120, entry €30, size 80 shares. Where's the money stop? (€120 ÷ 80 = €1.50 per share, so €28.50.)
2. Your stop is at €38 and price is at €38.10. What has changed about the trade's original reasoning? (Nothing. The pressure to move the stop comes from the open loss, and that's exactly why the level was decided earlier, while you were calm.)
3. Which number in course 4's expectancy formula does this lesson protect? (The average loss. A widened stop raises it, and expectancy drops with it.)

The habit this lesson installs

The stop is set before the entry and never widened after it.

Next: Course 6 — "Gap risk: when the stop can't save you."