The US share markets open between 9:30am - 4pm Eastern Time (1:30am - 8am NZ in winter and 3:30am - 10am in summer). 

If you make an order outside these hours, it will be placed on the share markets the next time they open again. In the hours between the market closing and the following day's opening bell, a number of factors can positively or negatively affect the price of shares, resulting in you receiving more or less shares than anticipated.

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