Power Hour

Power hour is the last 60 minutes of the Regular Trading Hours session, from 3:00 PM to 4:00 PM ET. It is the second most active period of the trading day after the opening range, and often produces strong directional moves as institutional flow concentrates near the close.

Why volume surges in the final hour

Closing price dependency: mutual funds, ETFs, and index funds execute large orders at or near the 4:00 PM close because their NAV is calculated based on closing prices. This predictable flow creates volume and often directional pressure.

Position management: day traders and intraday institutional desks close positions before the session ends, adding to volume.

Options expiration: on expiration Fridays, options market makers delta-hedge positions aggressively into the close, amplifying moves toward high-open-interest strike prices.

Futures settlement: the settlement price for many CME equity index futures is calculated using the closing prices of the underlying stocks, creating additional hedging activity near 4:00 PM.

Power hour trading characteristics

Power hour tends to produce one of two patterns:

Continuation: if the market has been trending all day, power hour often accelerates the trend as latecomers enter and short-covering (or long liquidation) adds momentum into the close.

Reversal: if price ran hard intraday, power hour sometimes sees a sharp reversal as profit-taking and rebalancing flows overwhelm the trend.

3:00 PM ET as a pivot

Many traders specifically mark 3:00 PM as a key time level. A market that is strong at 3:00 PM often stays strong into the close. A market that reverses at 3:00 PM can give back significant intraday gains quickly.

Power hour vs the opening range

The opening range and power hour are the two highest-edge periods for many day trading strategies. Lunch hours (12:00–2:00 PM ET) tend to be lower quality. Structuring your trading to be most active in the first and last hours of RTH is a time-tested approach to capturing the best setups.