Quick definition TWAP is an execution algorithm that divides a large order into equal parts and executes one part at regular time intervals (e.g., every 30 minutes) throughout the trading day. What it is TWAP is simple and mechanical. If you need to buy 1 million shares and trade over 5 hours with 10 time intervals, you buy 100,000 shares every 30 minutes. The average price you achieve is the time-weighted average of the market prices during those intervals. TWAP does not adapt to market conditions. It follows a fixed schedule regardless of volume, volatility, or price movement. Why it matters TWAP is passive and easy to execute. It requires no prediction of market conditions. It is useful for traders who want to execute quietly without drawing attention (executing large orders at random times is less visible to the market than executing all at once). TWAP also limits market impact by spreading execution over time. Rather than hitting the market with 1 million shares at once, you hit it with 100,000 shares repeatedly. TWAP versus VWAP VWAP (Volume-Weighted Average Price) adjusts execution timing to match expected volume, trading more during high-volume periods. TWAP trades equal amounts at equal time intervals, ignoring volume. VWAP typically results in better fills but requires predicting volume. TWAP is simpler and requires no predictions. Practical example You have 1 million shares to buy. You choose a TWAP algorithm with 10 intervals over the trading day (each interval 1 hour). The algorithm buys 100,000 shares every hour at the market price at that time. Hour 1: Market price is 50.00, you buy 100,000 shares at 50.00. Hour 2: Market price is 50.10, you buy 100,000 shares at 50.10. Hour 3: Market price is 50.05, you buy 100,000 shares at 50.05. ... Hour 10: Market price is 50.15, you buy 100,000 shares at 50.15. Your average fill is the average of the 10 prices, which is your TWAP. Variations Randomised TWAP executes at random intervals within each time bucket, rather than at fixed intervals. This further reduces market impact by making your order pattern less predictable. See also - VWAP (Volume-Weighted Average Price) - Market Impact - Execution Algorithm - Passive Algorithm
