This study examines formation and adaptation of reference prices by Manitoban grain producers. Research shows that preferences are reference‐dependent and marketing decisions are affected by reference prices. Results suggest that Manitoban producers’ reference prices are formed primarily by an average of recent prices and the highest price to‐date in the marketing window. Reference prices are found to adapt in the same direction as market prices, with adaptation to increasing prices being larger than adaptation to decreasing prices. When deciding to sell grain, producers are more likely to sell when they expect prices to decrease over the next month and when their reference price adjusts downwards towards the current price.