Commissions and any applicable taxes are debited from an account and reduce SMA. Fees, such as order cancellation fee, market data fee, etc. do not affect SMA. Cash withdrawals are debited from SMA and Cash deposits are credited to SMA. The IB Knowledge Base article for "What is SMA and how does it work" can be found by clicking here You can find the "SMA Rules" by scrolling down the IB Margin Education page
Does SMA change from Commissions, Taxes or Fees being debited?
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SMA (Special Memorandum Account)
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