Common Intraday Trading Mistakes

Updated October 23, 2026

Intraday traders repeat the same five mistakes, and none of them are about picking the wrong direction. They are about preparation, sizing and targets that the market cannot reach. Updated September 2026.

The five

• Trading without a tested plan

• Not understanding risk against reward

• Setting targets outside the instrument's typical daily movement

• Position sizing at random

• Ignoring the mental side entirely

1. Trading without a plan

This is the largest of the five. Without a plan there is no preparation, no research and no way to review what went wrong.

Intraday Trading Without a Plan

A plan specifies entry conditions and exit conditions. The point is that both are decided in advance, not in the moment when a position is already open and moving.

Build it by finding at least 50 historical instances of your entry and exit method, and adding up the results. That sample tells you whether the approach has an edge before you risk anything.

Not every trade needs to win. Winning 40 or 50 percent of trades produces a profitable system provided the winners are larger than the losers, which is what the next mistake is about.

2. Not understanding risk against reward

Successful traders generally target more reward than they risk, and the ratio is what makes a sub-50 percent win rate viable.

Suppose you enter a stock trade and place your stop 0.10 below entry. You are risking 0.10 per share. Setting the target at 0.20 to 0.30 means winning trades return two to three times what losing trades cost.

At a 2 to 1 ratio, winning four trades out of ten is breakeven and anything above that is profit. At a 1 to 1 ratio, the same win rate loses money steadily.

3. Targets outside typical movement

This is the mistake that quietly ruins otherwise sound plans, and it follows directly from the previous one.

A target of 0.25 per share is reasonable on a stock that moves several dollars per day. On a stock that moves 1.00 in an entire session, the same target requires a quarter of the day's total range in a single trade, which will rarely happen.

Check Average True Range for the instrument to establish typical daily movement, and check how far price waves run before pulling back. If the price has been moving 0.50 between pullbacks, place the target at 0.25 to 0.30 so it sits comfortably inside that range.

A target inside typical movement gets hit regularly. A target beyond it produces trades that go your way, stall short of the level, and reverse into a loss, which is the most demoralising outcome in intraday trading.

4. Random position sizing

Buying an arbitrary number of shares, lots or contracts makes the loss on each trade unpredictable, which makes the whole system unmeasurable.

Three inputs determine the correct size: your account balance, the distance between entry and stop loss, and the percentage of the account you will risk per trade.

Entering at 17.70 with a stop at 17.60 means risking 0.10 per share. On a 10,000 dollar account risking 1 percent, the limit is 100 dollars, which gives 1,000 shares. The calculation is arithmetic, not judgement.

5. Ignoring the mental game

Every decision passes through your own state at the time you make it, which makes the mental side as consequential as the strategy.

The advice to trade without emotion is unhelpful, because emotions occur whether or not they are permitted. What can be managed is the response to them.

A workable method is to define a rule in advance: after a loss that produces anger or frustration, stop and step away for five minutes before placing anything else. The break interrupts the sequence where one reactive trade follows another.

Note your state during the session rather than ignoring it. Recognising that you are frustrated is what allows the rule to be applied, and the note itself takes seconds.

The order to fix them

• Position sizing first, it makes every other result measurable

• Then the stop and target distances, checked against Average True Range

• Then the plan, tested across at least 50 historical instances

• Then the review process, so deviations are visible afterwards

• The mental rules last, they support the others rather than replacing them

See related trading guides and compare platforms in our forex brokers section.

Intraday mistakes: frequently asked questions

How many historical trades should I test?

At least 50 instances of your entry and exit method. That sample indicates whether an edge exists before you risk money.

What risk to reward ratio should I target?

Generally more reward than risk. At 2 to 1, winning four trades in ten is breakeven. At 1 to 1, the same win rate loses money.

How do I know if my target is realistic?

Check Average True Range for typical daily movement and how far price runs between pullbacks. The target should sit comfortably inside that range.

How do I calculate position size?

Divide your maximum acceptable loss by the distance from entry to stop. A 100 dollar limit with a 0.10 stop distance gives 1,000 shares.

Intraday Trading Without Position Size Rules

Can I trade without emotion?

No, and trying to is the wrong goal. Define a rule in advance, such as stepping away for five minutes after a frustrating loss.

Which mistake is most damaging?

Trading without a tested plan, because it makes every other element unmeasurable. Position sizing is the first one to fix.