A margin call happens when your account's equity falls so close to the amount required just to keep your open trades running that your broker steps in — either warning you to add funds or, increasingly, automatically closing positions to protect both you and the broker from a negative balance. It isn't a fee, a penalty, or something that happens at random; it's a mechanical consequence of running out of margin, and understanding that mechanism is the only real way to prevent one from happening to you.
What a Margin Call Actually Is
Every leveraged forex position requires two kinds of margin: initial margin, the deposit your broker locks up the moment you open the trade, and maintenance margin, the minimum equity you must keep in the account to hold that position open. A margin call is triggered when your equity drops toward that maintenance threshold — it's the broker's notification that your account no longer has enough of a buffer, and you need to either deposit more funds or reduce your exposure by closing positions.
The term dates back to when brokers genuinely phoned clients to demand more funds; today it's almost always an automated email, push notification, or on-platform alert. Babypips has a clear walkthrough of the mechanics in its lesson on what a margin call level is, which is worth reading alongside this if you want the concept reinforced from another angle.
Margin Level vs Used Margin vs Free Margin
Three numbers determine whether you're anywhere near a margin call, and mixing them up is the single most common source of confusion for newer traders:
- Used margin — the portion of your account currently locked up to keep your open positions running. It's not lost money; it's reserved and returned when you close the trade, but you can't touch it while the position is open.
- Free margin — the equity left over after used margin is set aside, calculated as equity minus used margin. This is what's actually available to open new positions or absorb further floating losses on existing ones.
- Equity — your account balance adjusted in real time for the floating profit or loss on every open position. Equity moves every time the market moves; balance only changes when a trade closes.
- Margin level — the ratio brokers actually watch, calculated as (equity ÷ used margin) × 100. This single percentage is what determines how close you are to a margin call or forced liquidation.
A quick illustration makes the relationship concrete. Imagine an account with $1,000 of equity currently using $200 of margin to hold its open positions: free margin is $800, and margin level works out to ($1,000 ÷ $200) × 100 = 500%, a comfortably healthy reading. Now suppose floating losses shrink equity to $250 while used margin stays at $200 — margin level drops to ($250 ÷ $200) × 100 = 125%, a much thinner cushion that's edging toward whatever threshold the broker has set for a margin call. Notice that used margin didn't change at all; it was equity falling that did the damage, which is exactly why watching margin level in real time matters more than watching balance.
How Margin Level Sets the Margin Call Threshold
A margin level of 100% means your equity exactly equals your used margin — every dollar of margin is committed and there's nothing left to absorb further losses. Brokers set their own margin call threshold, commonly somewhere around that 100% mark, and a separate, lower stop-out threshold where they'll start force-closing positions automatically if you haven't acted. These thresholds are broker-specific and can also vary by regulatory jurisdiction, so the exact numbers on your account may not match another trader's.
Regulators have taken an interest in this because retail leveraged trading carries real blow-up risk. In the UK, the FCA's rules for CFD providers require firms to close out a client's position once their funds fall to 50% of the margin needed to maintain it, alongside caps on maximum leverage and guarantees that a client can't lose more than the funds in their account. That 50% figure is a good illustration of how a stop-out level works in practice, even though your own broker's specific number will depend on where it's regulated and what account type you hold.
Reaching a margin call doesn't automatically mean your account goes to zero. But ignoring it typically ends in forced closures that lock in losses at whatever price the market happens to be at that moment — usually the worst possible moment, since margin calls cluster around fast, adverse price moves.
How Leverage Changes the Math
Leverage itself doesn't cause a margin call — position size relative to your equity does. What leverage changes is how easy it becomes to open a position that's too large for your account. Higher leverage lowers the margin required to open a given position, which frees up more of your equity as "available" — but if you use that freed-up capacity to open an even bigger position, your used margin as a share of a larger, more volatile exposure erodes your equity buffer faster with every pip that moves against you.
In other words, two traders using wildly different leverage settings can carry identical real risk if they size their positions accordingly, and two traders using the same leverage can have completely different margin-call risk depending on how large a position they actually open. For the full relationship between leverage, margin requirement, and position size, PipDesk's leverage and margin explained article covers that mechanism in depth.
How to Avoid a Margin Call
- Size positions from risk, not from available leverage. Just because your broker allows a large position doesn't mean it fits your account — use a position size calculator to size trades from your stop distance and risk tolerance instead.
- Keep a real buffer of free margin. Running an account with margin level hovering near 100% as a routine practice leaves no room for normal volatility before you're staring at a call.
- Monitor margin level, not just balance. Balance only updates when trades close; margin level reflects your real-time risk and is the number that actually matters while positions are open.
- Use stop losses on every trade. A defined exit prevents one losing position from spiraling into an account-wide margin problem.
- Watch combined exposure across all open positions, not just one trade. Several correlated positions can drain free margin just as fast as one oversized one — PipDesk's drawdown calculator and the article on understanding drawdown are useful for seeing that bigger picture.
Margin Call vs Stop Out: Know the Difference
A margin call is a warning — it tells you the account needs attention but generally still leaves you in control of the decision. A stop out is what happens if that warning goes unaddressed: the broker automatically closes positions, usually starting with the most unprofitable one, until the margin level recovers above the stop-out threshold. Some brokers separate the two clearly with distinct percentages and a notification in between; others skip the warning stage entirely and move straight to closing trades once the stop-out level is breached. Because this varies so much by broker, it's worth checking your specific platform's margin call and stop-out levels directly rather than assuming they match what you've read elsewhere.
A margin call is never really the root problem — it's the symptom of a position sized too large for the account carrying it. Before opening a trade, running the numbers through a margin calculator to see exactly how much margin it requires and how far price would need to move against you to threaten your margin level takes a few seconds and removes most of the guesswork that leads to one.