A margin account is a brokerage account where your broker lends you money, using the investments in your account as collateral, so you can buy more securities than your cash would otherwise allow. You pay interest on the loan, and any rise or fall in your position applies to the full amount you bought, not just the part you paid for.
That single detail explains almost everything beginners get wrong. Borrowing does not reduce risk or reliably raise returns. It moves your entry point, your cost and your worst case all at once.
Below is a plain look at how margin accounts work and their risks, written for US readers who have never traded on borrowed money. Rules and rates differ by country and change over time, so treat the figures here as typical rather than permanent. This is general education, not individual investment advice.
Table of Contents
- What Is a Margin Account?
- Cash Account vs. Margin Account at a Glance
- How Margin Accounts Work and Their Risks, Step by Step
- How a Margin Purchase Is Made
- What Can Make You Lose More Than Your Cash
- How Interest on Borrowed Money Works
- Maintenance Requirements and Margin Calls
- What Happens During a Forced Liquidation
- The Main Risks of Trading on Margin
- Who Is a Margin Account Best For?
- What to Check Before Opening a Margin Account
- Frequently Asked Questions
- Can I lose more than the cash I put in a margin account?
- What happens if I do not pay a margin call?
- Do margin accounts have annual fees?
- Is margin interest tax-deductible?
- Can I use margin in an IRA?
- Conclusion
What Is a Margin Account?
A margin account lets your broker loan you cash, secured against the securities you already hold or the ones you are buying. In exchange for that loan you pay interest, and the broker can sell your holdings if the value of your account falls below its rules.
The main participants in US markets are you, your broker-dealer, and the clearing firms and exchanges that hold and settle the securities. Your broker is the one that extends the loan, sets its own house maintenance requirement, and decides when to call collateral or liquidate a position.
Two things follow from the arrangement. First, the account can magnify gains and losses, because your percentage return is measured against your own cash while the price move applies to the whole position. Second, a loss is not capped at your deposit, so a position can leave you owing money rather than simply shrinking.
Cash Account vs. Margin Account at a Glance
The cleanest way to see the difference is to compare the two side by side.
| Feature | Cash account | Margin account |
|---|---|---|
| Money available to invest | Only settled cash you deposited | Cash plus borrowed funds |
| Interest cost | None on securities you hold | Variable margin interest on borrowed value |
| Can you sell shares you do not own? | No | Yes, subject to rules and requirements |
| Margin call | Not applicable | Yes, when equity falls below the requirement |
| Forced liquidation | Not applicable | Yes, if a call is not met in time |
| Opening minimum | Varies, often no minimum | Typically 2,000 dollars of equity |
| Pattern day trader rule | Does not apply | Applies below 25,000 dollars of equity |
| Worst realistic case | Account value falls toward zero | Account value falls below zero; you owe the difference |
Many US brokers open new accounts with margin approval switched on by default. Forum threads on r/Wealthsimple and r/fidelityinvestments are full of people who did not realise their long position was being financed, and asked why they were charged interest or hit with a call on shares they thought were fully paid for.
How Margin Accounts Work and Their Risks, Step by Step
Here is how margin accounts work and their risks in the order they actually happen.
- You deposit cash and eligible securities. Some investments qualify as marginable collateral, others do not, and the broker values them at a reduced rate.
- You gain buying power. That is your equity plus the amount the broker is willing to lend.
- You buy. Under Federal Reserve Regulation T, you generally must put up 50 percent of the purchase price yourself, so the maximum initial borrowing on a stock purchase is half its value.
- Interest accrues. It is charged daily on the borrowed balance and billed monthly, even if the position does not move.
- You keep equity above the maintenance requirement. Fall below it and the broker issues a margin call, then can liquidate your holdings.
Equity is the number that matters most. Take your cash plus the market value of your holdings, then subtract what you owe the broker. That figure is your equity, and it is what every margin rule is measured against.
| Requirement | Typical level | What it governs |
|---|---|---|
| Initial margin requirement (Regulation T) | 50 percent of purchase price | How much you must contribute when you buy |
| Broker house maintenance requirement | Often 25 to 40 percent, depending on the security | How much equity must remain as prices fall |
| General margin account minimum | 2,000 dollars | Equity required to open and keep the account open |
| Pattern day trader threshold | 25,000 dollars | Extra rules for frequent day trades in a margin account |
How a Margin Purchase Is Made
Suppose you deposit 4,000 dollars and buy 10,000 dollars of stock, borrowing the remaining 6,000 dollars. Your debit balance is 6,000 dollars, your position is worth 10,000 dollars, and your equity is 4,000 dollars.
| What happens to the stock | Position value | You owe | Your equity | Change in your cash |
|---|---|---|---|---|
| Rises 20 percent | 12,000 dollars | 6,000 dollars | 6,000 dollars | Up 50 percent |
| Unchanged | 10,000 dollars | 6,000 dollars | 4,000 dollars minus interest | Down, interest only |
| Falls 20 percent | 8,000 dollars | 6,000 dollars | 2,000 dollars | Down 50 percent |
| Falls 40 percent | 6,000 dollars | 6,000 dollars | Zero | Down 100 percent plus interest |
Owning the same 10,000 dollars of stock without borrowing, a 20 percent fall costs you 20 percent. With a 60 percent loan, the identical move costs half your own money. That is the arithmetic behind every number in the table, and it is also why a flat market is not free.
What Can Make You Lose More Than Your Cash
A steep decline is the obvious route to a negative balance. Price gaps make it worse, because a stock can fall sharply overnight and leave no chance to sell at a price you would have accepted.
Concentration does the same damage more reliably. Hold one stock on margin and that single company’s bad news becomes your account value. Experienced traders on r/interactivebrokers consistently advise using far less than the maximum permitted amount and keeping marginable securities spread across unrelated names.
Options and other leveraged products add a layer on top, since their value can move non-linearly against you. And short positions carry theoretically unlimited loss, because a price can keep climbing.
How Interest on Borrowed Money Works
Margin interest is almost always variable, not fixed. Your broker sets its own base rate, and it sits above a published benchmark that tracks short-term US interest, so your rate moves when the central bank moves and can change without notice.
The practical pattern is benchmark rate plus broker spread. Competitive brokers quote margins in the low-to-mid single digits on top of that benchmark, while some charge double or more, so the spread can matter more than the base rate. Recent rate surveys put typical advertised rates somewhere around 5 percent to 12 percent or higher.
Interest accrues daily on your debit balance and is deducted monthly, and it compounds if you leave the loan open. A 10,000 dollar position financed with 6,000 dollars at 9 percent costs about 45 dollars a month, roughly 540 dollars a year, for the privilege of waiting.
Maintenance Requirements and Margin Calls
The initial requirement governs what you must supply when you buy. The maintenance requirement governs what must remain as prices move, and it is stricter in the sense that it is the one that ends accounts.
Brokers set a house maintenance requirement, and FINRA sets the floor at 25 percent for most securities, with higher levels for volatile or thinly traded names. House requirements are not fixed: they can be raised at any time, sometimes without advance notice, and a broker can ask you to deposit cash or sell shares immediately.
You have roughly two to five business days, depending on the broker and the margin agreement, to meet a margin call. Ways to respond are limited: deposit cash, transfer in settled securities, or sell part of the position. Waiting to see if the price recovers is the option most likely to end badly.
What Happens During a Forced Liquidation
A forced liquidation is the step after the call goes unanswered. Your broker sells enough of your holdings to bring the account back into compliance, and it may do so without waiting for your approval or for the market to reopen at a better price.
Three things make this the sharpest edge in the whole account. The sale can happen at the worst hour of a falling market, you are charged the spread on a trade you did not choose to make, and the loan plus accrued interest still has to be repaid out of whatever the sale produced.
If the account falls below the 2,000 dollar minimum, brokers may restrict new buying activity or require you to bring the balance back up. Persistent failure to meet a call can end the relationship entirely, and any negative balance becomes a debt you owe the firm.
The pattern is not new. Margin calls drove the forced selling that deepened the 1929 crash, and again in 2008 when leveraged holders had to liquidate into a falling market. Different decades, same mechanic.
The Main Risks of Trading on Margin
The downsides of having a margin account are worth reading as a list, because they stack.
- Amplified losses. Your percentage return is calculated on your own cash while the price move applies to the entire position, so a modest move becomes a large percentage change.
- Debt. A negative balance is money owed, with interest attached, and it does not disappear because you closed the position.
- Gap risk. Overnight news can move a price past any stop level you set.
- Concentration risk. One company’s failure can trigger a call on your whole account.
- Margin call and forced liquidation. Your broker can require cash or sell your holdings on its own schedule.
- Interest rate risk. Rates rise without warning and the cost of holding flat positions climbs with them.
- House requirement risk. Your broker can raise its own requirement whenever it chooses.
- Tax consequences. Interest is generally deductible only against investment income, and short sales can create tax bills even on a losing trade.
- Counterparty exposure. Your account is an unsecured claim on a brokerage firm, covered only up to SIPC limits and not at all for market losses.
- Behavioral pressure. Watching a borrowed position swing every day produces exactly the rushed decisions that turn a bad week into a permanent loss.
Short selling deserves its own note: losing trades on a short can exceed the amount borrowed, because there is no ceiling on how far a price can climb.
Who Is a Margin Account Best For?
Margin suits investors who already know the securities they trade, keep a written plan for repaying borrowed funds, and could absorb a large loss without touching rent, groceries or emergency savings. Active traders with a high tolerance for drawdowns are the typical users.
It is a poor fit for beginners, for long-term buy-and-hold investors, and for anyone who could not add funds on short notice. Forum discussion on long-term index investors is instructive here: most describe using a small amount, roughly 2x at most, purely as a convenience, and treat anything higher as a strategy they do not run.
If you are starting out, a cash account, a target-date fund or a broad index fund puts the same money to work without a loan, an interest bill or a broker holding a forced-sale trigger over your head.
What to Check Before Opening a Margin Account
Work through this list before you sign anything.
- Eligibility and minimums. Most US brokers require 2,000 dollars of equity to open and keep a general margin account open.
- The actual margin interest rate, not the headline. Find the benchmark link and the spread, then work out the dollar cost on a 6,000 dollar balance held for a year.
- House maintenance requirements for the securities you plan to trade, which may sit well above 25 percent.
- Which assets are permitted. IRAs, 401(k)s, 403(b)s and UGMA or UTMA accounts are not eligible for margin.
- Trading rules. If you day trade, the 25,000 dollar pattern day trader threshold changes what you are allowed to do in a margin account.
- Liquidation policy. Find the written deadline for meeting a call and the order in which securities are sold.
- Fees beyond interest, including commissions, fees for services like sweeps or data, and any account minimums.
- Housekeeping details. Most brokers default new accounts to margin, so find how to opt out if you want a cash account instead.
- Credit reporting. Ask whether the margin agreement is subject to a credit check and how missed payments are handled.
- Tax treatment and how interest is reported on your statement.
Read the margin agreement itself, not just the summary page. Several long-term investors report that reading the agreement first was the thing that stopped them opening one at all.
Frequently Asked Questions
Can I lose more than the cash I put in a margin account?
Yes. Losses on a margin position are not capped at your deposit or at the value of your collateral. If a 6,000 dollar financed position falls to 4,000 dollars while you owe 6,000 dollars, your equity is negative 2,000 dollars and that becomes a debt owed to your broker, with interest continuing to accrue. The SEC and investor.gov both warn that margin accounts are not appropriate for every investor.
What happens if I do not pay a margin call?
Your broker can sell securities in your account to cover the shortfall, and may do so without waiting for your consent. The sale typically happens within two to five business days of the call, often during a falling market, and you pay the spread on the trade. Interest and any resulting negative balance remain, so an unresolved call can move from a fee into a debt you owe the firm.
Do margin accounts have annual fees?
There is no single mandatory annual fee, but the cost usually shows up in several places. The main one is margin interest charged on borrowed value. Some brokers also charge account maintenance fees below a balance threshold, plus separate fees for services such as wire transfers, extended hours quotes or order routing. Read the fee schedule, because a low trading fee does not offset a wide margin spread.
Is margin interest tax-deductible?
In the US, margin interest is generally deductible only against investment income, and only if you itemise deductions. If you have no investment income, the interest is effectively wasted, and in some cases it produces a carryforward that gives you no current benefit at all. Interest charged on a margin loan used to buy securities is not the same as a home mortgage interest deduction.
Can I use margin in an IRA?
No. Margin is not available inside IRAs, 401(k) plans, 403(b) plans or UGMA and UTMA custodial accounts, because regulations require those assets to be held without borrowing against them. If you want to borrow against a large portfolio instead, look at securities-based lending, which is a separate product with its own risks, its own rate and its own collateral rules.
Conclusion
The central risk of a margin account is simple to state: you are betting borrowed money on a price, and the broker holds the trigger. A 20 percent adverse move does something manageable to your own cash and something severe to your position.
Start by reading the full margin agreement, work out what a year of interest would cost on the amount you plan to borrow, and check whether your broker has switched margin on by default. If the answer to any of that is unclear, keep the account in cash until it is not.
Whatever you decide, only commit money you can afford to lose without changing your plans.
