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Chart Patterns and William O'Neil: Integrating Technical Analysis with CAN SLIM Fundamentals

From TradingHabits, the trading encyclopedia · 4 min read · March 1, 2026
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William O'Neil's CAN SLIM system is a masterful blend of fundamental and technical analysis. While the "C" and "A" of the system focus on a company's earnings, the "N" for New High and the chart patterns that O'Neil favored are pure technical analysis. For the experienced trader, understanding how to integrate chart patterns with fundamental analysis is a important skill for identifying high-probability trading setups.

The Importance of Chart Patterns

Chart patterns are the footprints of the big money. They are the visual representation of the supply and demand dynamics of a stock. A stock that is under accumulation by institutional investors will form a distinct chart pattern, such as a cup and handle or a flat base. These patterns are a sign that the stock is coiling for a big move.

O'Neil's research showed that the market's biggest winning stocks all had one thing in common: they all broke out of a sound chart pattern before they made their big move. This is why he placed such a strong emphasis on chart analysis. He understood that the chart is a leading indicator, and that it can often tell you what a stock is going to do before the fundamentals are widely known.

The Classic O'Neil Patterns

O'Neil identified a number of classic chart patterns that are associated with super-stocks. These include:

  • Cup and Handle: This is the most famous of the O'Neil patterns. It is a bullish continuation pattern that is formed after a stock has had a strong uptrend. The cup is a "U" shaped consolidation, and the handle is a slight downward drift in price. The breakout from the handle is the buy signal.
  • Flat Base: This is a sideways consolidation pattern that is formed after a stock has had a strong advance. The stock will trade in a tight range for a period of at least five weeks. The breakout from the top of the base is the buy signal.
  • Double Bottom: This is a bullish reversal pattern that is formed after a stock has had a significant decline. The stock will make two distinct lows at roughly the same price level. The breakout above the intervening peak is the buy signal.

These are just a few of the classic O'Neil patterns. The key is to learn to recognize these patterns and to understand the psychology behind them.

Integrating Chart Patterns with Fundamentals

While chart patterns are a effective tool, they should not be used in isolation. The most effective trading setups are the ones that have both a strong chart pattern and strong fundamentals. This is the essence of the CAN SLIM system.

When you find a stock with a perfect cup and handle pattern, the next step is to check its fundamentals. Does it have strong earnings growth? Does it have a new product or service? Is it a leader in its industry? If the answer to these questions is yes, then you have a potential super-stock on your hands.

By combining technical analysis with fundamental analysis, you can increase your odds of success and avoid the pitfalls of trading on just one or the other. A stock with a great chart but terrible fundamentals is a recipe for disaster. A stock with great fundamentals but a broken chart is a stock that is not yet ready to move.

The Art of the Buy Point

The buy point is the specific price at which you should enter a trade. For a cup and handle pattern, the buy point is the high of the handle. For a flat base, the buy point is the high of the base. It is important to buy the stock as it is breaking out of the pattern, not after it has already had a big run.

O'Neil was a stickler for buying at the proper buy point. He knew that a stock that is bought at the right price has a much higher probability of success. He also knew that a stock that is bought at an extended price is more likely to fail.

By mastering the art of chart patterns and integrating them with the fundamental principles of the CAN SLIM system, you can develop a effective and effective trading strategy. It is a strategy that has been proven to work time and time again, and it is a strategy that can help you to achieve your financial goals.