Is that why in thinkorswim there is a total under the heading margin balance?

Yes—that’s related. Thinkorswim is basically doing two things: 1. **Per‑position margin requirement** – the column you saw next to each stock. 2. **A total under “Margin Balance” / “Margin Req”** – the **sum of all those requirements** at the account level. That total is **not an extra fee** and **not automatically debt**; it’s just: > “Here’s how much of your equity we’re setting aside as margin requirement to support all these positions.” What you really care about for *borrowing* is different: - Look in your **Account Info / Balances** area for something like: - **“Margin debit”**, **“Margin balance (debit)”**, or similar. - Interpret it as: - **0** → you’re not borrowing on margin. - A **negative / red number** → that’s the actual **dollar amount you’ve borrowed**. - The “margin balance” total under your positions is just a **risk requirement number**, not the amount you owe. So: - **Yes**, the total under “margin balance” is there *because* TOS calculates a margin requirement for each stock and then totals it. - **No**, that total by itself doesn’t mean you’re in trouble or heavily margined; it’s just showing you how much “room” your positions consume. If you tell me: - Whether your **margin debit** (or similar line) is 0 / positive / negative, I can translate exactly whether you’re actually borrowing or just seeing normal margin requirements.