Quote from osorico:
It depends how your trading accounts are titled and how you file taxes. As an individual without an exchange seat, gains are taxed at the blended 23% rate. Period. No self-employment tax needed. But you also have no "earned income", so you can not make contributions to retirement plans, or write off other items requiring earned income, such as health related expense.
This scenario is completely different if you trade via a business structure with or without an exchange seat. The business facilitates your trading, and you are paid from the business. The business enjoys the benefits of business, including preferential tax treatment of futures trading, employee benefits, writeoffs, etc, and you enjoy the benefits of earned income and company benefits, along with being subject to self employment tax more affectionately known as FICA. Your employment arrangement dictates how the fica (self-employment) tax is handled. For example independent contractor or payrolled.
Osorico