Margin Call Price Calculator
Calculate the price at which a margin call is triggered on a leveraged stock position. Enter your purchase price, initial margin, and maintenance margin requirement to find the margin call threshold.
How to use this tool
- Enter purchase price per share, initial margin requirement and maintenance margin requirement in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your margin call price and the full breakdown beneath it.
⚠ This tool provides general estimates for education only and is not financial, tax or legal advice. Figures may not reflect your situation — verify with a qualified professional.
Formula
Loan Amount = Purchase Price × (1 − Initial Margin)
Margin Call Price = Loan Amount / (1 − Maintenance Margin)
Equivalently: Margin Call Price = Purchase Price × (1 − Initial Margin) / (1 − Maintenance Margin)
How it works
When buying on margin, the broker lends the portion of the purchase price not covered by the investor's initial margin. A margin call is triggered when the equity in the account (current price minus loan) falls to the maintenance margin level. Setting equity equal to the maintenance margin fraction of the current price and solving for that price gives the margin call threshold.
Worked example
Stock purchased at $50, 50% initial margin, 25% maintenance margin
- Loan per share = 50 × (1 − 0.50) = 50 × 0.50 = $25
- Margin Call Price = 25 / (1 − 0.25) = 25 / 0.75 = $33.33
- Price Drop = 50 − 33.33 = $16.67 (33.33% decline)
Margin call is triggered if the share price falls to $33.33 — a drop of $16.67 (33.33%) from purchase
Common mistakes to avoid
- Using equity value instead of loan amount in the numerator — the margin call price formula divides the fixed loan amount (borrowed dollars) by (1 - maintenance margin), not total position value.
- Forgetting that the loan amount is fixed in dollar terms; as the stock price falls, the equity percentage falls while the loan stays constant, which is exactly what triggers the margin call.
- Confusing initial margin (minimum equity required to open a position) with maintenance margin (minimum ongoing equity ratio); these are different thresholds and the margin call is triggered by the maintenance requirement.
Key terms
- What is a margin call?
- A margin call occurs when the equity in a margin account falls below the broker's required maintenance margin level. The investor must deposit more funds or sell securities to restore the account to the minimum level.
- What is the initial margin requirement?
- The initial margin is the minimum percentage of a stock purchase the investor must fund with their own money. Under Regulation T in the US, this is typically 50%.
- What is the maintenance margin?
- The maintenance margin is the minimum equity percentage that must be maintained in a margin account after the initial purchase. FINRA requires at least 25%, though brokers often set higher minimums.
- What happens if I get a margin call?
- If you receive a margin call you must either deposit additional cash or securities, or sell holdings to bring your account equity back above the maintenance margin level, usually within 2–5 business days.
- What is a loan amount in margin trading?
- The loan amount (or debit balance) is the portion of the stock purchase funded by the broker. It equals Purchase Price × (1 − Initial Margin) and remains fixed regardless of price movements.
Frequently asked questions
- What happens if I receive a margin call?
- You must either deposit additional cash or marginable securities into your account, or sell enough securities to bring the equity ratio above the maintenance margin level. If you do not act quickly, your broker may liquidate positions without your consent.
- Can I avoid margin calls by setting a stop-loss order?
- A stop-loss can help by automatically selling before the margin call price is reached, but stop orders are not guaranteed to execute at the stop price in fast-moving markets. They reduce but do not eliminate margin call risk.
- What is a typical maintenance margin requirement in the US?
- FINRA requires a minimum maintenance margin of 25% equity for long positions. Many major brokers set house requirements at 30-40% to provide a buffer above the regulatory minimum.