What happens if I sell a position with fractional shares?
Closing your position with fractional shares is straightforward and can be managed online. If the stock symbol you wish to sell does not support fractional trading, please proceed by selling all whole shares first. Then, for any remaining fractional shares, send an email to service@firstrade.com. In your email, make sure to specify the stock symbol and the quantity you wish to liquidate.
For more information, please visit https://help.en-us.firstrade.com/article/887-fractional-trading