Margin lending lets customers control more securities than their own capital would buy. What two concerns does the regulation of margin accounts under FINRA Rule 4210 respond to?

Unequal access to credit between retail and institutional customers, and margin interest charged at rates above those the banks themselves charge

Customer losses beyond the customer's capacity to absorb them, and instability from leverage building up across the financial system

Tax avoidance through purchases made with borrowed money, and the movement of customer cash into accounts carrying no deposit insurance

Excessive commissions earned on heavily leveraged accounts, and conflicts arising when firms lend against securities they underwrote themselves

A member firm proposes a maintenance requirement of twenty percent for its longest-standing customers, judging them creditworthy enough not to need the level FINRA Rule 4210 sets. May the firm apply a twenty percent maintenance level to those customers?

Yes; a house requirement may depart from the regulatory minimum in either direction where the firm records its reasons

Yes, provided each customer agrees in writing to the lower level at the time the margin account is opened

No; a firm's house requirement may be more stringent than the regulatory minimum, not less stringent

No; a lower figure needs FINRA's prior approval for each customer account the firm would apply it to

A member carries margin accounts guaranteed by one guarantor, and the margin deficiencies in them total $450,000. The member's excess net capital is $3,000,000. When the member computes net capital under SEC Rule 15c3-1, how does FINRA Rule 4210 treat those guaranteed deficiencies?

$150,000 is charged against net capital, the part of the guaranteed deficiencies above ten percent of its excess net capital

The whole $450,000 is charged against net capital, since the guaranteed deficiencies have passed ten percent of its excess net capital

$300,000 is charged against net capital, being ten percent of its excess net capital, the guarantor bearing the rest of the deficiencies

Nothing is charged against net capital, a deficiency that another party guarantees being that guarantor's liability and not the member's

A member wants to value the positions in a customer's margin account at later prices than the trade price or the prior day's close when it determines the intraday margin level. What does FINRA Rule 4210 require of the member?

FINRA's approval of the more recent pricing source, obtained for each customer account to which the member applies it

A written procedure reasonably designed to make its computations more current, not to reduce intraday margin requirements

Nothing further, the member using whatever price it judges fairest provided the customer is told which prices were used

A written procedure under which the more recent price is used only where it is lower than the execution price, to hold requirements down

A customer buys stock in a margin account, and the initial margin Regulation T requires is not received within the Regulation T payment period. The deficiency is large, and the firm has not applied to its examining authority for an extension. What must the broker-dealer then do?

Carry the position and charge a penalty rate of interest on the unpaid amount until the customer deposits it

Liquidate securities sufficient to eliminate the whole deficiency, even where meeting the call itself would need less

Liquidate securities sufficient to meet the margin call or to eliminate the deficiency then existing, whichever is less

Treat the shortfall as a maintenance call and allow the time it allows on maintenance calls

A customer buying stock on margin wants to meet the Regulation T initial requirement by depositing fully paid marginable shares transferred from another firm rather than cash. Is that permitted?

No; the initial deposit must be made in cash, securities being accepted against maintenance calls instead

Yes, but only where the shares are of the same issuer as the stock being bought on margin

No; deposited securities count toward the initial deposit once the firm has sold them for cash

Yes; eligible securities as well as cash meet the initial deposit that Regulation T requires

A customer bought forty-eight thousand dollars of stock with twenty-four thousand dollars borrowed. The stock is now worth thirty-one thousand dollars. Measured against FINRA Rule 4210's twenty-five percent minimum, is there a maintenance margin deficiency?

Yes; equity of $7,000 is below the $7,750 required on the stock's current market value

No; equity of $7,000 exceeds twenty-five percent of the $24,000 debit balance owed to the firm

Yes; equity of $7,000 is below the $12,000 required on the price originally paid for the stock

No; the maintenance requirement is tested only when a new purchase is made in the account

Many member firms set house maintenance requirements of thirty percent or more for equity securities. What judgment lies behind setting the figure above the FINRA Rule 4210 minimum?

That a higher house level qualifies the firm's margin lending for cheaper funding from the banks it borrows from

That the regulatory minimum leaves too thin a cushion against rapid adverse price movements in volatile markets

That the regulatory minimum is meant for exempt securities, equity securities needing a figure each firm sets

That a firm applying a higher house level may then lend more than Regulation T allows on new purchases

What does the Margin Disclosure Statement tell a customer about the member firm's house maintenance margin requirements?

That an increase applies to positions bought after the firm announces it, not to existing ones

That the firm must give the customer thirty days' written notice before any increase takes effect

That the firm may increase them at any time, without giving the customer advance notice

That the firm may increase them once FINRA approves the change for that class of security

Under FINRA Rule 4210's pattern day trader framework, how was a pattern day trader's day trading buying power calculated?

As up to four times the maintenance margin excess, recalculated in real time from open intraday positions

As up to twice the account's total equity, recalculated in real time from open intraday positions

As up to twice the account's total equity, measured from the account's end-of-day equity

As up to four times the maintenance margin excess, measured from the account's end-of-day equity

Critics raised several objections to FINRA Rule 4210's pattern day trader framework. Which of these was among them?

That labelling a customer either a pattern day trader or not ignored wide variation in actual intraday risk

That it treated a short sale closed by a purchase later the same day as falling outside the count of day trades

That it reached only customers' cash accounts, leaving intraday trading in margin accounts outside the rule

That it obliged a firm to approve each of a designated customer's day trades before the order was executed

A customer uses a margin account mainly for long-term holdings and makes a day trade only a few times a year. Is the account within the reach of the intraday margin standard that took effect under FINRA Rule 4210 on June 4, 2026?

Yes, once the firm has designated the account as an active trading account in its own records

Yes; it reaches customer margin accounts other than good faith and portfolio margin accounts, at any trading frequency

No; the standard reaches only accounts whose equity falls below a fixed dollar minimum at some point during the day

No; the standard reaches only accounts whose day trades make up most of their trading in any calendar month

A customer's margin account is under the ninety-day restriction that FINRA Rule 4210 imposes for intraday margin deficits left unsatisfied. Which of these may the firm's procedures still allow the customer to do?

Sell short a stock the firm has located, provided cash is deposited to cover the margin

Buy further shares on margin, provided its equity stays above the maintenance level afterwards

Sell shares already held long in the account, using the proceeds to reduce its debit balance

Borrow against the shares held in the account to withdraw cash, provided its equity stays above the maintenance level afterwards

Under FINRA Rule 4210's intraday margin framework, which combination of conditions requires the member firm to enforce the ninety-day trading restriction?

It leaves any single intraday deficit unmet past the close of the fifth business day, whatever its record of meeting deficits before

It leaves any single intraday deficit unmet past the close of the trading day on which that deficit first arose in the account

It makes a practice of failing to meet intraday deficits promptly and leaves one unmet past the close of the trading day it arose

It makes a practice of failing to meet intraday deficits promptly and leaves one unmet past the fifth business day's close

A customer's portfolio margin account, carried on its own, has a margin deficit. Her ordinary margin account at the same member holds excess equity larger than that deficit. Under FINRA Rule 4210, how can the deficit be met from that excess?

By transferring funds or securities into the portfolio margin account and keeping a written record, the excess itself not satisfying the deficit

The deficit counts as satisfied once the member notes that the other account's excess equity exceeds it, no transfer or record of one being needed

By transferring funds or securities into the portfolio margin account, with FINRA's written approval of each such transfer and of the customer's reasons for it

Only by closing out the positions in the portfolio margin account, whatever excess equity the customer's other accounts at the member hold

FINRA Rule 4210 requires less margin on a covered call position than on an uncovered call written on the same stock. What accounts for the difference?

The covered position is guaranteed by the clearing corporation, which does not stand behind uncovered writers

In the covered position the underlying shares held protect the writer against an adverse price movement

The covered writer receives a larger premium for the same call, and the rule counts the premium as margin

A covered call cannot be assigned before its expiration date, so the writer faces no early demand to deliver

FINRA Rule 4210 determines the intraday margin level immediately after each transaction that reduces it. A customer's margin account holds a long option whose expiration lowers the cash she could withdraw while still meeting maintenance margin. Is the expiration a transaction of that kind?

Yes, but only if she bought the option the same day, an option carried from an earlier day being left out of the level's determination

No; a purchase or a short sale that the customer enters is what reduces the level, an expiration happening without any instruction from her

Yes; the expiration counts although no order was entered, since such transactions are not confined to purchases and short sales

No; an expiration bears on the maintenance requirement at the close of business, not on the level determined during the day

FINRA Rule 4210 sets specific margin requirements for security futures, the exchange-traded futures contracts on individual equity securities. What do those requirements reflect?

That a security future is an exempt security, margined in good faith by the firm in the way Treasury issues are

That a security future is guaranteed by the company whose stock it is on, so margin need cover only that issuer's credit

That a security future carries the loss of an uncovered call, and so takes the margin schedule for uncovered calls

That a security future is leveraged and replicates an equity position, while carrying risk and leverage unlike an outright purchase

Under FINRA Rule 2264, which works alongside FINRA Rule 4210, which customers must receive the Margin Disclosure Statement, and when?

Non-institutional customers, before or at the time the margin account is opened

Every customer, institutional ones included, before or at the time the margin account is opened

Non-institutional customers, within ten business days after their first purchase made on margin

Every customer, institutional ones included, within ten business days after their first purchase on margin

A customer's margin call has gone unmet, and the firm is selling securities in her account to eliminate the deficiency. She instructs the firm to sell her bond fund and leave her technology shares untouched. Must the firm follow the instruction?

No; the firm must sell the positions bought most recently on margin before any other positions

No; the customer is not entitled to choose which securities are sold to meet a margin call

Yes, provided the bond fund's sale raises enough to eliminate the whole deficiency in one step

Yes; a customer's instruction on which positions to sell binds the firm once a call has gone unmet

Under FINRA Rule 4210, what outer time limit applies to obtaining the margin or mark to market that any provision of the rule requires?

Thirty calendar days from the date of the deficiency, unless FINRA has specifically granted the member additional time

Fifteen business days from the date of the deficiency, unless the member itself extends the time for that customer

Fifteen business days from the date of the deficiency, unless FINRA has specifically granted the member additional time

Thirty calendar days from the date of the deficiency, unless the member itself extends the time for that customer

Two margin customers each meet every Regulation T call by selling securities in the account instead of depositing funds; neither account is carried on an omnibus basis. At each sale A's account holds more than FINRA Rule 4210's maintenance equity and B's holds less. Whose practice must the member not permit?

Neither, a Regulation T call met in full within the payment period being satisfied however the funds are raised

A's only, B's sales being needed to bring the account back up to the equity the rule requires it to maintain

Both, the prohibition reaching every customer who meets calls by liquidation, whatever the account's equity at each sale

B's only, the prohibition not reaching an account that complies with the rule's maintenance equity when the sale is made

Trading in one listed stock becomes disorderly. Under FINRA Rule 4210, what may FINRA itself do about the margin required on that stock?

Prescribe higher initial margin for new transactions in that stock and higher maintenance margin, without amending the rule's text

Prescribe lower maintenance margin on that stock for a period, so that forced selling by margin customers does not deepen the disorder

Nothing directly, since a different requirement for a single stock takes an amendment to the rule that the SEC has approved

Raise the Regulation T initial margin on that stock, the Federal Reserve Board having delegated that power over margin to FINRA

Purchases one morning leave a customer's margin account short of the maintenance margin FINRA Rule 4210 requires; at two in the afternoon she deposits cash covering the shortfall. What allowance does the rule give the member for that deposit in determining the day's intraday margin deficit?

None; the deposit counts at two in the afternoon, so a deficit stands for the morning and must be met by a later deposit

It may count the deposit as made immediately after the start of the day, offsetting the shortfall the morning purchases would create

It may count the deposit as made at the close, so that it reduces only a deficit carried into the next business day

It may count the deposit as made at the start of the day, but only where she told the member of it before the open

On one day a customer's margin account records the purchase of one stock and the sale of another stock bought earlier that day, and the member cannot show which of the two occurred first. On what assumption does FINRA Rule 4210 have the member compute the account's intraday margin level?

That they occurred in the order the customer says she placed them, unless the member has evidence against her

That they occurred in whichever order produces the lowest intraday margin deficit, the doubt favouring the customer

That they occurred in whichever order produces the highest intraday margin deficit for that day in the account

That each moved the level by half its full effect, the average of the two possible orders being taken

A member operates a bank sweep program under which a margin customer's cash is held as deposits at FDIC-insured banks. Under FINRA Rule 4210, how may the member treat those deposits when it computes her intraday margin level?

As collateral valued at half its amount, because the deposits are held outside the member's own custody

Not at all, because cash held at the program banks lies outside the account until it is swept back into it

As a credit balance, but only to the extent the deposits at each bank fall within the FDIC insurance limit

As a credit balance in her margin account, under a written policy the member follows for sweep deposits

Under FINRA Rule 4210's portfolio margin provisions, how is the margin required for each portfolio of positions in a security class determined?

The greater of the largest theoretical loss at any one of ten equidistant valuation points or a per-contract minimum, values coming from an SEC-approved model

The lesser of the largest theoretical loss at any one of ten equidistant valuation points or a per-contract minimum, values coming from a model the member selects

The greater of the average theoretical loss across ten equidistant valuation points or a per-contract minimum, values coming from a model the member selects

The lesser of the average theoretical loss across ten equidistant valuation points or a per-contract minimum, values coming from an SEC-approved model

A customer whose options approval covers spreads but not the writing of uncovered options asks her member firm to open a portfolio margin account. Under FINRA Rule 4210, may the firm open it?

Yes; her spread approval suffices, spreads being the hedged positions that a portfolio margin account is designed to recognise

No; only eligible participants approved for uncovered short option contracts under FINRA Rule 2360 are permitted to use one

Yes, provided the account she asks for is not an individual retirement account, to which the provisions do not apply

No; portfolio margin accounts are open only to institutional customers, individual customers being confined to strategy-based margin

At the close of business the equity in a customer's portfolio margin account is less than the margin required, and over the following three business days she neither deposits funds or securities nor establishes a hedge. Under FINRA Rule 4210, what follows?

The firm may go on accepting any opening orders the remaining equity supports, and need liquidate only if the equity falls further

The firm must liquidate every position in the account at once and transfer the account to strategy-based margin

The firm may accept only opening orders that reduce market risk, and must liquidate positions if the deficiency remains

The firm must obtain FINRA's approval before it accepts further orders or liquidates any position in the account

A customer has two margin accounts at one member firm: one shows a surplus over its required margin and the other a deficiency. Under FINRA Rule 4210, on what condition may the member determine the margin to be maintained on the net position of the two accounts?

FINRA has approved the combination on the member's application, after reviewing the customer's trading in both accounts

The accounts are held in the same name and of the same type, so that the customer's identity alone links them for margin

The member records the netting in writing at the end of each day and keeps that record available for FINRA's inspection

The customer has consented to the use of the money and securities in each to carry or pay any deficit in both

FINRA Rule 4210 | Financial Regulation Courses

Understanding Margin Requirements

FINRA Rule 4210 — Margin Requirements — establishes the comprehensive regulatory framework governing the extension of credit by FINRA member firms to customers in margin accounts — specifying the initial margin that customers must deposit when purchasing securities on credit, the maintenance margin that must be maintained in the account at all times after purchase, the margin call procedures that apply when account equity falls below required levels, and — following SEC-approved amendments effective June 4, 2026 — a modernised intraday margin standard that replaced the long-standing pattern day trader framework with a requirement that member firms determine the intraday margin deficit that a customer's trading creates during the day and require it to be satisfied as promptly as possible.

Margin accounts enable customers to purchase securities using funds borrowed from the broker-dealer — amplifying both the potential gains and potential losses of investment activity by allowing the customer to control more securities than they could afford to purchase outright with their own capital.

The regulatory framework governing margin accounts reflects the dual investor protection and market stability concerns that leveraged investing creates — protecting individual investors from losses that exceed their financial capacity to absorb while preventing systemic instability from excessive leverage accumulation across the financial system.

Rule 4210 supplements the Federal Reserve Board's Regulation T — which establishes the initial margin requirements for securities purchases — by imposing additional maintenance margin requirements and comprehensive risk management obligations that apply throughout the life of the margin account.

Member firms may impose house margin requirements that are more stringent than both Regulation T and Rule 4210's minimums — but may not apply requirements less stringent than the regulatory minimums.

Regulation T and Initial Margin — The Federal Framework

The initial margin requirement — the percentage of a securities purchase that must be deposited by the customer in cash or eligible securities at the time of purchase — is established by Federal Reserve Board Regulation T rather than by FINRA Rule 4210 directly.

Regulation T currently requires an initial margin deposit of fifty percent of the purchase price for most equity securities — meaning that a customer purchasing ten thousand dollars of stock in a margin account must deposit at least five thousand dollars of their own capital, with the remaining five thousand dollars financed by the broker-dealer as a margin loan.

The initial margin requirement establishes the maximum leverage available to customers at the time of purchase — no more than two-to-one leverage for most equity securities under the current fifty percent initial margin requirement.

The initial margin must be deposited within the Regulation T payment period — currently three business days after the trade date for most securities transactions, the payment period being the number of business days in the standard settlement cycle, now one business day after the trade date, plus two business days — or the broker-dealer must liquidate securities sufficient to meet the margin call or to eliminate the margin deficiency existing on the day the liquidation is required, whichever is less, unless the payment period has been extended on the firm's application to its examining authority or the deficiency created or increased is one thousand dollars or less.

Failure to pay the required initial margin within the payment period creates a Regulation T deficiency that triggers specific regulatory consequences including potential restrictions on future trading in the account.

FINRA Rule 4210 implements Regulation T's framework at the self-regulatory organisation level and supplements it with maintenance margin requirements, margin call procedures, and additional provisions addressing specific account types and trading strategies not fully covered by Regulation T.

Maintenance Margin — The FINRA Rule 4210 Standard

While Regulation T establishes the initial margin requirement at the time of purchase, FINRA Rule 4210 establishes the maintenance margin requirement — the minimum equity that must be maintained in a margin account at all times after the initial purchase.

The standard maintenance margin requirement under Rule 4210 is twenty-five percent of the current market value of the margined securities — meaning that the customer's equity in the account must equal at least twenty-five percent of the current market value at all times. As the value of margined securities changes after purchase the required maintenance margin changes proportionally — declining market values reduce the equity in the account while the maintenance margin requirement remains at twenty-five percent of the current lower value.

When the value of margined securities falls sufficiently that the customer's equity drops below the twenty-five percent maintenance margin threshold a maintenance margin deficiency exists — and the member firm must issue a margin call requiring the customer to deposit additional cash or securities to restore the account to compliance. The margin call must typically be satisfied promptly — most member firms require margin calls to be met within two to five business days — and the member firm retains the right to liquidate securities in the account without prior notice to the customer if the margin call is not met.

Member firms routinely impose house maintenance margin requirements above the Rule 4210 minimum of twenty-five percent — commonly thirty percent or higher for equity securities — reflecting the practical risk management judgment that the regulatory minimum does not provide adequate protection against rapid adverse price movements in volatile markets. The Margin Disclosure Statement required by FINRA Rule 2264 informs customers that member firms may increase their house maintenance margin requirements at any time without advance notice.

Time Limits, Liquidation Practices and FINRA's Power to Raise Requirements

Rule 4210 places an outer limit on how long a member firm may wait for the margin its requirements call for. The amount of margin or mark to market required by any provision of the rule must be obtained as promptly as possible and in any event within fifteen business days from the date the deficiency occurred, unless FINRA has specifically granted the member additional time — so the house practice of calling for deposits within a few business days operates inside a regulatory ceiling, and a firm cannot extend a customer's time beyond that ceiling on its own authority.

The rule also governs how customers meet Regulation T margin calls. When a margin call as defined in Regulation T is required in a customer's account, no member may permit the customer to make a practice either of deferring the deposit of cash or securities beyond the time when the transactions would ordinarily be settled or cleared, or of meeting the margin required by liquidating the same or other commitments in the account — a customer who habitually buys on margin and then sells to cover the resulting call, rather than depositing funds, is engaged in exactly the practice the rule forbids firms to permit.

The prohibition on liquidations does not apply to an account that, at the time of the liquidation, is in compliance with the equity to be maintained under the provisions of Rule 4210, nor to an account carried on an omnibus basis as prescribed by Regulation T.

Rule 4210 also reserves to FINRA a power to raise requirements above the rule's own figures. Notwithstanding the rule's other provisions, FINRA may, whenever it determines that market conditions so warrant, prescribe higher initial margin requirements for new securities transactions and commitments in customer accounts with respect to specific securities, higher maintenance margin requirements for customer accounts with respect to any securities, and such other terms and conditions relating to initial or maintenance margin as it deems appropriate — so the regulatory minimum for a particular security can rise without any change to the text of the rule.

The 2026 Intraday Margin Amendments

The most significant change to FINRA Rule 4210 in its history — amendments approved by the SEC on April 14, 2026 and effective June 4, 2026, with members that needed more time permitted to phase in their implementation until October 20, 2027 — fundamentally restructured the rule's approach to day trading by eliminating the pattern day trader framework that had governed intraday trading activity since 2001 and replacing it with a new intraday margin standard designed to align margin requirements more closely with real-time intraday trading risk.

The prior pattern day trader framework defined a pattern day trader as any customer who executes four or more day trades within five business days where those trades represent more than six percent of the customer's total trades for the period. Pattern day traders were required to maintain minimum equity of twenty-five thousand dollars in their margin account at all times — regardless of the size or frequency of their actual intraday positions — and were permitted to trade up to four times their maintenance margin excess as day trading buying power.

The limitations of the pattern day trader framework had been a subject of industry and investor concern for years — the twenty-five thousand dollar minimum equity requirement was seen as an arbitrary barrier that prevented many retail investors from accessing legitimate intraday trading strategies, the four-times buying power calculation was based on end-of-day equity rather than real-time intraday positions creating potential for excessive intraday leverage, and the binary pattern day trader designation failed to account for the wide variation in actual intraday risk across different customers and trading strategies.

The new intraday margin standard replaces the pattern day trader concept entirely — applying to all customer margin accounts other than good faith accounts and portfolio margin accounts, regardless of the customer's trading frequency — and requires each member firm to determine the intraday margin deficit, if any, for each such account on every day on which the account has a transaction reducing its intraday margin level — a firm being free to monitor positions in real time and block transactions that would create or increase a deficit, but not required to, since it may instead make a single calculation of the deficit, as firms do for maintenance margin at the end of the day. When an intraday margin deficit exists — meaning the customer's account equity has fallen below required levels based on current intraday positions — the member firm must take prompt action to address the deficit.

Measuring the Intraday Margin Deficit

The intraday margin standard works through the intraday margin level — the amount of cash the customer could withdraw while still having the maintenance margin the rule requires, or, expressed as a negative number, the cash the customer would need to deposit to have it — determined immediately after each transaction that reduces that level. A transaction that reduces the level is not confined to a purchase or a short sale: any withdrawal of cash or securities from the account counts, and so does the expiration of a long option in the account where the expiration reduces the level.

A member firm may treat all deposits and withdrawals of cash or securities made during the day, and any transaction that closes a position open at the beginning of the day, as occurring simultaneously and immediately after the beginning of the day, whatever their actual time — so a deposit made in the afternoon, or the sale of a position carried overnight, may offset a deficit that morning purchases would otherwise have created. A firm may likewise treat as simultaneous the execution of the several legs of a spread, or of another strategy carrying a reduced maintenance requirement, where they result from a single order or are executed substantially contemporaneously, and the creation of a position by the assignment or exercise of an option together with the liquidation of that position on the same day.

Where the firm's records cannot settle the sequence of events, the rule resolves the doubt against the account. Outside those allowances, if two or more activities occurred in a margin account during a day and the firm cannot demonstrate that one occurred before another, the intraday margin level is computed on the assumption that they occurred in the order that produces the highest intraday margin deficit for the day. A firm may also value positions at prices more recent than the execution price or the previous business day's closing price, but only under a written procedure reasonably designed to make its computations more current rather than to reduce intraday margin requirements.

Margin Calls and Remediation

When a margin deficiency exists — whether a maintenance margin deficiency arising from adverse price movements in existing positions or an intraday margin deficit under the new intraday standard — the member firm must take prompt action to restore the account to compliance.

The member firm may require the customer to deposit additional cash or securities sufficient to eliminate the deficiency — the traditional margin call that requires the customer to contribute additional capital. If the customer fails to meet a margin call within the required timeframe the member firm has the authority — and in some circumstances the obligation — to liquidate securities in the account to eliminate the deficiency without prior notice to and without the consent of the customer.

The right to liquidate without notice — disclosed in the Margin Disclosure Statement required by FINRA Rule 2264 — is one of the most important and most frequently misunderstood features of margin accounts. Many retail investors mistakenly believe they will always receive advance warning and an opportunity to respond before their securities are sold to meet a margin call — the margin disclosure requirement exists specifically to correct this misunderstanding and ensure customers understand the firm's right to liquidate before they experience it in practice.

Under the new intraday margin framework if a customer makes a practice of failing to satisfy intraday margin deficits as promptly as possible and fails to satisfy a deficit by the close of business on the fifth business day after it occurs the member firm must enforce written policies and procedures reasonably designed to prevent the customer from creating or increasing a short position or debit balance for ninety calendar days after that fifth business day or until the intraday margin deficit has been satisfied.

Allowances Within the Intraday Margin Standard

The ninety-day restriction is directed at a customer's conduct over time rather than at an isolated lapse, and the rule identifies two kinds of intraday margin deficit that cannot establish that conduct. A customer is not to be considered as making a practice of failing to satisfy intraday margin deficits as promptly as possible because of deficits that do not exceed the lesser of five percent of the equity in the margin account or one thousand dollars — in an account with equity of ten thousand dollars that ceiling is five hundred dollars, while in an account with equity of one hundred thousand dollars it is one thousand dollars.

The second kind is a deficit that the member firm reasonably determines to have occurred under extraordinary circumstances, such that the failure to satisfy it does not reflect a practice of failing to satisfy intraday margin deficits as promptly as possible. The determination belongs to the firm but must be reasonable, and it bears only on whether the customer is treated as making a practice — the separate requirement that the firm require every intraday margin deficit to be satisfied as promptly as possible still applies to the deficit itself.

The rule also lets a firm recognise customer cash held outside the account through a program the firm itself operates. Where a member operates a sweep program under which a customer's funds are held as deposits at FDIC-insured banks, it may follow a written policy of treating the aggregate amount of that customer's sweep deposits as a credit balance in the margin account when it computes the intraday margin level and any intraday margin deficit — a treatment FINRA has said members may apply whether or not the customer does any day trading.

Special Margin Requirements — Specific Securities and Strategies

Rule 4210 establishes special margin requirements for specific categories of securities and trading strategies that present different risk profiles than standard equity margin positions.

Options positions are subject to specific margin requirements under Rule 4210 — with different margin treatments for long options positions, covered options positions, spread strategies, and uncovered naked options positions. The margin requirements for options reflect the different risk characteristics of each strategy — uncovered naked options positions that carry potentially unlimited loss exposure require substantially higher margin than covered positions where the underlying security provides protection against adverse price movements.

Short sale positions — where a customer sells securities they do not own, borrowing them from the broker-dealer or a third party — are subject to specific margin requirements under Rule 4210 that recognise the theoretically unlimited loss potential of short positions. A short seller who sells shares at fifty dollars faces unlimited potential loss if the price rises without bound — requiring margin protection that reflects this asymmetric risk profile.

Security futures — exchange-traded futures contracts on individual equity securities — are subject to specific margin requirements that reflect both the leveraged nature of futures contracts and the unique risks of single-stock futures that can be used to replicate equity positions with different risk and leverage characteristics than outright equity purchases.

Portfolio Margin — The Risk-Based Alternative

As an alternative to the strategy-based requirements set out in the rest of Rule 4210, member firms may elect to apply portfolio margin requirements to margin equity securities, listed options, security futures products, unlisted derivatives, warrants and related instruments. Positions are grouped by security class into portfolios, theoretical gains and losses within each portfolio may be netted fully at each valuation point, and the requirement for each portfolio is the greater of the largest theoretical loss at any of ten equidistant valuation points or a fixed minimum for each contract — the theoretical values coming from a pricing model that must be approved by the SEC.

Portfolio margin is not open to every margin customer. Only eligible participants that have been approved to engage in uncovered short option contracts under FINRA Rule 2360 are permitted to use a portfolio margin account, and the portfolio margin provisions do not apply to individual retirement accounts at all.

A portfolio margin deficiency runs on a fixed timetable. If at the close of business the equity in the account is less than the margin required, the customer may deposit additional funds or securities, or establish a hedge, within three business days; after that period the firm may not accept new opening orders other than orders that reduce market risk and would lower the margin requirement, and if the deficiency has still not been eliminated the firm must liquidate positions sufficient, at a minimum, to bring the total margin required down to no more than the account equity. A deficit in the portfolio margin account cannot be treated as satisfied by excess equity in another of the customer's accounts — funds or securities must be transferred into the deficient account and a written record kept — unless the portfolio margin account is carried as a sub-account of a margin account.

Connection to Margin Disclosure and Customer Education

Rule 4210 works in conjunction with FINRA Rule 2264 — which requires delivery of the Margin Disclosure Statement to non-institutional customers before or at the time of opening a margin account — creating a comprehensive customer education and regulatory protection framework that ensures customers understand the mechanics and risks of margin trading before they begin using borrowed funds to amplify their investment exposure.

The Margin Disclosure Statement's required content — explained in detail in the FINRA Rule 2264 entry of this dictionary — directly reflects Rule 4210's key provisions — the right to liquidate without notice, the right to change margin requirements, the right to sell securities without contacting the customer first, and the inability to choose which securities are sold to meet a margin call. Together Rule 4210 and Rule 2264 ensure that the substantive margin regulatory framework and the customer disclosure obligations are aligned — the rules customers must follow are the same rules they are informed about before their account is opened.

Combined and Guaranteed Accounts

Rule 4210 sets conditions on combining a customer's accounts for margin purposes. Where two or more accounts are carried for the same customer, the margin to be maintained may be determined on the net position of those accounts only where the customer has consented that the money and securities in each may be used to carry or pay any deficit in all of them — without that consent a surplus in one of the customer's accounts does not cover a deficiency in another.

An account guaranteed by another account may also be consolidated with the guaranteeing account, with the margin to be maintained determined on the net position of both, but only where the guarantee is in writing and permits the member carrying the account, without restriction, to use the money and securities in the guaranteeing account to carry the guaranteed account or to pay any deficit in it. A guarantee of that kind cannot, however, be used to meet portfolio margin requirements.

Guarantees carry a capital consequence for the carrying firm. When the total margin deficiencies guaranteed by any one guarantor exceed ten percent of the member's excess net capital, the amount of the guaranteed deficiency above that ten percent must be charged against the member's net capital when it computes net capital under SEC Rule 15c3-1.

Examination Relevance and Key Takeaways

FINRA Rule 4210 is tested on the Series 7 examination extensively in the context of margin accounts, initial and maintenance margin requirements, margin calls, and the regulatory framework governing leveraged investing.

The key points to retain are these.

FINRA Rule 4210 — Margin Requirements — establishes the maintenance margin framework supplementing Federal Reserve Board Regulation T's fifty percent initial margin requirement for equity securities. The standard maintenance margin requirement is twenty-five percent of the current market value of margined securities — when account equity falls below this threshold a margin call requires the customer to deposit additional cash or securities. Member firms may impose higher house maintenance margin requirements. The member firm has the right to liquidate securities without prior notice to meet margin calls — disclosed in the Margin Disclosure Statement required by FINRA Rule 2264.

The SEC approved amendments to Rule 4210 effective June 4, 2026 replacing the pattern day trader framework with a new intraday margin standard. The prior pattern day trader framework — defining any customer executing four or more day trades in five business days as a pattern day trader requiring twenty-five thousand dollars minimum equity — has been eliminated.

The new intraday margin standard requires member firms to determine intraday margin deficits for customer margin accounts regardless of trading frequency, whether by monitoring and blocking transactions in real time or by a single end-of-day calculation. Customers who repeatedly fail to satisfy intraday margin deficits face ninety-day trading restrictions. Special margin requirements apply to options, short sales, and security futures positions reflecting their distinct risk profiles.