how opening price works
the nasdaq uses the opening cross approach to calculate opening prices based on the orders that accumulated overnight typically a security s opening price differs from the last day s closing price 1 after hours trading has changed investor valuations or expectations for the security factors that can affect the opening priceafter the market closes corporate announcements and other news can change investor expectations and the next day s opening price some investors may try to buy or sell securities when large scale disasters occur after hours not all orders are executed during after hours trading there is much less liquidity during this time producing wider bid ask spreads this makes orders unattractive because it s more challenging to complete a transaction at a predictable price and limit orders often won t be filled 