In Elliott Wave Theory, a Flat Wave is a common corrective wave pattern within the broader market cycle. It is characterized by a three-wave structure labeled as A-B-C, where the waves move sideways or in a horizontal range rather than trending strongly in one direction. This pattern reflects a period of consolidation or balance in the market, often occurring after a strong impulsive wave.

The Flat Wave differs from other corrective patterns, such as Zigzags and Triangles, in its structure and behavior. Unlike a Zigzag, which has a sharp, steep correction with a clear 5-3-5 wave structure, a Flat Wave tends to be more balanced and less volatile. It typically retraces less of the preceding impulsive wave compared to a Zigzag. Additionally, Flat Waves can take three forms: Regular Flats, Expanded Flats, and Running Flats. In a Regular Flat, wave B retraces close to the start of wave A, and wave C ends near the end of wave A. In an Expanded Flat, wave B exceeds the start of wave A, and wave C extends beyond the end of wave A. Running Flats are rare and occur when wave C fails to reach the end of wave A.

The key distinction lies in the market sentiment. Flat Waves indicate a balance between bullish and bearish forces, whereas Zigzags show a stronger counter-trend movement. Traders use Flat Waves to identify potential continuation points in the trend, as they often precede the resumption of the dominant impulsive wave. Understanding this pattern helps traders anticipate market behavior and make informed decisions.