You can borrow against stocks by pledging the shares in your brokerage account as collateral, either through a margin loan built into that account or through a separate securities-backed line of credit. Federal rules cap your initial borrowing at 50 percent of the portfolio’s market value.1eCFR. 12 CFR 220.12 – Supplement: Margin Requirements Interest tends to run lower than unsecured debt because the lender holds your securities as security, and you avoid the capital gains taxes that would come with selling. The tradeoff is that the lender can liquidate your holdings without warning if the account value drops too far, and you remain personally on the hook for any shortfall.
Pick the Right Product: Margin Loan or SBLOC
Two products dominate this space, and they behave differently even though both use your stocks as collateral.
A margin loan sits inside a brokerage margin account. You borrow against the equity in that account, and the funds can be used for anything, including buying more securities. Regulation T, administered by the Federal Reserve, governs these accounts and sets the initial borrowing limits.2eCFR. 12 CFR Part 220 – Credit by Brokers and Dealers (Regulation T)
A securities-backed line of credit, usually called an SBLOC, is a separate credit facility that your brokerage or an affiliated bank extends against your investment account. The important distinction is that SBLOC proceeds generally cannot be used to buy more securities. Federal Regulation U prohibits lenders from extending credit secured by margin stock when the purpose of that credit is to purchase or carry additional margin stock.3eCFR. 12 CFR Part 221 – Credit by Banks and Persons Other Than Brokers or Dealers (Regulation U) SBLOCs are built for non-investment uses: a home renovation, a tax bill, bridging a real estate closing, covering business expenses.
SBLOCs typically require larger portfolios. Firms often want at least $100,000 in eligible assets before approving one, while a standard margin account can be opened with as little as $2,000 in equity.4FINRA. Securities-Backed Lines of Credit Explained Some SBLOC lenders skip the credit check entirely and base your limit on portfolio value alone. That speeds approval, but it also tells you the lender is relying on the collateral rather than your broader financial picture.
Setting Up the Account
If you already hold securities in a cash-only account, you apply for margin privileges through your brokerage’s online platform, usually under account settings or trading preferences.5FINRA. Margin Regulation The application asks for your Social Security number, employment status, annual income, net worth, and liquid assets. The firm uses this to set your risk profile and credit limits.
FINRA Rule 4210 requires at least $2,000 in cash or eligible securities before you can open a margin position.6FINRA. FINRA Rule 4210 – Margin Requirements Many firms set higher minimums, especially for dedicated credit lines. You’ll sign a margin agreement spelling out the firm’s right to liquidate your holdings if account value drops below required levels, the interest rate structure, and the conditions under which the firm can change your terms. Read it before signing. The liquidation clause is the part that surprises people later.
Not every holding in your portfolio counts toward borrowing power. Regulation T defines “margin securities” to include stocks listed on major exchanges, Nasdaq-listed securities, most mutual funds and ETFs registered under the Investment Company Act, and certain foreign stocks meeting trading volume and market-cap thresholds.7eCFR. 12 CFR Part 220 – Credit by Brokers and Dealers (Regulation T) – Section 220.2 Definitions Penny stocks, thinly traded shares, and newly issued IPO stock during a lock-up period are typically non-marginable. You can hold them in a margin account, but they won’t add to your borrowing capacity.
Drawing the Funds
Once your account or SBLOC is approved, drawing money is straightforward. Most platforms display your available borrowing power in real time. You choose a dollar amount and a destination: a linked checking account, an external bank account via ACH, or a wire transfer. Internal transfers between linked accounts at the same institution often post the same day. ACH to external banks usually takes one to three business days.
No separate credit application happens at the point of withdrawal. The collateral is already pledged, so the system just verifies that the requested amount doesn’t exceed your available margin. Larger draws may trigger an internal review by the firm’s risk department, adding hours rather than days. Speed and simplicity are the main appeal compared to a traditional bank loan.
How Much You Can Borrow
The federal ceiling on your initial borrowing is 50 percent of the current market value of the securities.1eCFR. 12 CFR 220.12 – Supplement: Margin Requirements On a $200,000 portfolio, that means an initial cap of $100,000. Individual firms often lend less than the federal maximum, particularly against volatile stocks or concentrated positions.
Concentration is where borrowers usually get surprised. If your portfolio is heavily weighted in one or two names, the brokerage will likely impose higher margin requirements on those positions, cutting your effective borrowing power. FINRA Rule 4210 requires firms to evaluate whether concentrated positions represent “undue risk” and to set margin requirements accordingly.6FINRA. FINRA Rule 4210 – Margin Requirements A $500,000 portfolio spread across 30 blue-chip stocks will almost always have more borrowing capacity than a $500,000 position in a single tech company.
What It Costs
Interest accrues daily on your outstanding balance and is typically charged to your account monthly. Rates are usually benchmarked to the Secured Overnight Financing Rate (SOFR), which sat at approximately 3.70 percent in early 2026. SBLOC rates commonly run two to three percentage points above SOFR, with the spread narrowing as account size grows. Margin loan rates at brokerages follow a similar tiered structure, though the specific benchmarks and spreads vary by firm.
Many firms charge no application fee, origination fee, or prepayment penalty on SBLOCs. You pay interest only on what you actually draw, not on the full credit line. The catch is that rates are variable. If SOFR rises, your borrowing cost rises with it, and there is no contractual cap on how high it can go.
Margin Calls and Forced Liquidation
This is the part that determines whether borrowing against stocks works out or blows up. Your account must maintain a minimum equity level at all times. FINRA Rule 4210 sets the regulatory floor at 25 percent of the total market value of the securities in the account.6FINRA. FINRA Rule 4210 – Margin Requirements Most firms impose stricter house requirements, typically between 30 and 40 percent, and sometimes higher for volatile or concentrated positions.8SEC. Understanding Margin Accounts
If equity falls below the maintenance threshold, you face a margin call. The reality here is harsher than most borrowers expect. Your brokerage is not required to notify you before selling securities. FINRA is explicit: firms do not have to issue a margin call before liquidating, they do not have to let you choose which positions are sold, and they can sell enough to pay off the entire margin loan rather than just the shortfall.9FINRA. Know What Triggers a Margin Call Some firms extend a courtesy notice and a short window to deposit funds, but they are not obligated to.
A sharp market drop on a Monday morning can result in your broker selling your best holdings by Monday afternoon, locking in losses at exactly the wrong time. You have no legal path to stop the sale once maintenance is breached, because the margin agreement you signed grants the firm that authority.
Other Risks Worth Weighing
The margin call is the sharpest risk, but it isn’t the only one.
Margin loans are recourse debt. If a forced liquidation doesn’t cover the loan balance, you owe the difference personally. Your downside is not capped at the value of the collateral. In a fast-moving market, and especially with concentrated positions, the gap between what you owe and what the sale recovers can be significant.
Concentration compounds the danger. A single earnings miss or sector rotation can drop one stock 20 to 30 percent in a day, cutting through your maintenance cushion before you can respond. If you hold a large position in your employer’s stock, think hard before leveraging it further.
Securities in a margin account can also be re-pledged. Your broker has the legal right to lend or re-hypothecate those shares to other market participants, subject to federal limits tied to aggregate customer indebtedness.10eCFR. 17 CFR Part 240 Subpart A – Hypothecation of Customers’ Securities In practice, your shares may be lent to short sellers. You keep economic ownership, but you can lose voting rights on lent shares, and dividends may arrive as “payments in lieu of dividends,” which can carry less favorable tax treatment.
Interest keeps accruing whether the market is up or down. If you borrow and stocks fall, your collateral shrinks while your debt grows. Investors who plan to let interest compound on the assumption that portfolio growth will outpace it are betting on a market that doesn’t always cooperate. Bear markets can last years, and variable rates may rise at the same time.
Tax Treatment
Loan proceeds themselves are not taxable income. You received money, but you also took on an obligation to repay it, so there is no net gain to tax. The point of borrowing rather than selling is that you avoid realizing capital gains on appreciated shares. For investors holding stock with large unrealized gains, especially in higher brackets, the deferral can be worth real money.
Interest paid on margin loans may be deductible as investment interest expense, but only up to your net investment income for the year, which includes dividends, interest, and short-term capital gains. Excess interest carries forward to future years.11Internal Revenue Service. Form 4952 – Investment Interest Expense Deduction You have to itemize to claim it, so there is no benefit if you take the standard deduction.
Two nuances matter. Interest used to generate tax-exempt income, such as borrowing to buy municipal bonds, is not deductible. And if you use an SBLOC for personal expenses rather than investment purposes, the interest is generally not deductible at all, because it isn’t allocable to investment property. Getting the allocation right is worth a conversation with a tax professional before you assume you can write it off.
Paying It Back
Most margin loans and SBLOCs have no fixed repayment schedule. You can pay down the balance whenever you want through cash deposits, by selling securities in the account, or by transferring funds from an outside bank. Some borrowers make regular monthly payments to keep the balance in check. Others let it ride and pay it off in a lump sum when they eventually sell shares or come into cash.
The flexibility is genuinely useful, and also genuinely dangerous. Monthly interest that rolls into principal compounds quietly. Borrow $50,000 at 6 percent, make no payments, and the balance climbs to roughly $53,000 in a year before you spend another dollar. Treating the loan as indefinite free money is the mistake that shows up most often, and it tends to surface during the next market downturn, when you have the least room to absorb it.