Margin Call Calculator
Find the share price at which your broker will issue a margin call. Enter the purchase price, the share of it you borrowed and your broker’s maintenance requirement. Add today’s price to see your current equity percentage and, if you are below it, how much cash to deposit or stock to sell.
Last updated:
Reg T allows up to 50% for most stocks; 50% loan = 50% initial margin.
Reg T: 50%, on top of the short sale proceeds (150% total).
FINRA minimum is 25% for long stock; many brokers require 30–40%, and 30%+ for shorts.
Shows your equity % now and how much to deposit if you are in a call.
How to use the Margin Call Calculator
- Choose long or short. Long means you bought shares with a margin loan; short means you sold borrowed shares.
- Enter the price and shares, then the margin loan % (long) or the initial margin you deposited (short).
- Enter your broker’s maintenance requirement, such as 25%, 30% or a higher house requirement for a volatile stock.
- Optionally add the current price to see your equity % now and what it takes to meet a call.
- Click Calculate call price and review the steps, table and chart.
Margin call formulas
| Position | Equity | Margin call price |
|---|---|---|
| Long (bought on margin) | shares × price − loan | loan ÷ (shares × (1 − m)) = P₀ × loan% ÷ (1 − m) |
| Short sale | credit balance − shares × price | P₀ × (1 + initial margin) ÷ (1 + m) |
Here m is the maintenance requirement as a decimal and P₀ is the purchase or short sale price. Equity % is equity divided by the current market value of the position.
How far can a stock fall before a margin call?
For a long position with a 50% margin loan, the drop you can absorb depends only on the maintenance requirement:
| Maintenance requirement | Call price (bought at $100, 50% loan) | Drop before a call |
|---|---|---|
| 25% | $66.67 | 33.3% |
| 30% | $71.43 | 28.6% |
| 35% | $76.92 | 23.1% |
| 40% | $83.33 | 16.7% |
| 50% | $100.00 | 0% (call immediately) |
Borrowing less widens the cushion: with a 25% loan and a 25% maintenance requirement, the call price is $100 × 0.25 ÷ 0.75 = $33.33, a 66.7% drop.
Ways to avoid a margin call
- Borrow less than the maximum, so the price can fall further before equity reaches the requirement.
- Know your broker’s house requirement for each holding; it can be much higher than 25% for a single volatile stock.
- Keep spare cash or set alerts near your margin call price.
- Remember that interest charges add to the loan and slowly raise the call price.
Frequently asked questions
What is the margin call price formula?
For a long position: margin call price = purchase price × (loan % ÷ (1 − maintenance %)). Buying at $100 with a 50% loan and a 25% maintenance requirement gives $100 × 0.50 ÷ 0.75 = $66.67, a 33.3% drop. For a short sale: call price = short price × (1 + initial margin %) ÷ (1 + maintenance %).
What is a maintenance margin requirement?
It is the minimum equity you must keep in a margin account, as a percentage of the current market value of the securities. FINRA sets a minimum of 25% for long stock positions, and brokers often set higher “house” requirements, especially for volatile, concentrated or low-priced stocks.
How much do I need to deposit to meet a margin call?
Enough to bring equity back up to the maintenance level: maintenance % × market value − current equity. If equity is $8,000 on a $27,500 position with a 30% requirement, you need 0.30 × $27,500 − $8,000 = $250.
Why does selling stock to meet a call take more than the deposit amount?
Selling shares repays part of the loan but also shrinks the market value, so your equity stays the same. You have to sell enough that equity ÷ remaining value reaches the requirement: market value − equity ÷ maintenance %.
How long do I have to meet a margin call?
It depends on the broker, often two to five business days, but a broker can sell your securities without notice and without waiting, especially in fast-moving markets. Read your margin agreement.
Can I lose more than I invested on margin?
Yes. If the price falls below the point where equity reaches zero (loan ÷ shares for a long position), the account owes the broker money. On a short sale, losses can keep growing as the price rises.
Does margin interest change the margin call price?
Yes, slightly. Unpaid interest is added to the loan balance, which raises the call price over time. Use the margin interest calculator to estimate how much it adds.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.