With the transition of accounts from TD Ameritrade to , OBP is now managed through the Schwab platform, though the core thinkorswim engine still handles the underlying calculations. Core Calculations by Account Type
is the total capital currently available in your account to open new options positions. It differs from your total cash balance because it accounts for margin requirements, open orders, and funds that haven't fully settled yet. option buying power td ameritrade
Your available OBP depends heavily on your account classification: With the transition of accounts from TD Ameritrade
When you place a trade, your OBP is reduced by the "Buying Power Effect" (BPE): What Is Options Buying Power? - tastylive Your available OBP depends heavily on your account
OBP is strictly equal to your settled cash . You cannot use margin or leverage; you must pay the full premium upfront for any option purchase.