Brokerage Account Basics: What SIPC Covers and What It Doesn't

A brokerage account is a container. That's the sentence that clears up most of the confusion around it. It is not an investment, it does not have a return, and opening one accomplishes nothing on its own — a fact that a surprising number of people discover years later when they log in and find their money still sitting in cash, exactly where they left it.

What follows is general education, not investment advice, and nothing in it forecasts returns — past performance does not predict future results, and a brokerage account carries no promise of any outcome at all. It covers what the container is, what protections come with it, what protections emphatically do not, and the handful of default settings that quietly cost people money.

Taxable versus tax-advantaged: same broker, different rules

Most brokerages will open you either kind, on the same platform, holding the same investments. The difference is entirely how the IRS treats what happens inside.

A tax-advantaged account — a traditional or Roth IRA, a 401(k), an HSA — comes with a contribution limit and rules about when money can come out. For 2026 the IRS set the IRA contribution limit at $7,500, with a $1,100 catch-up from age 50, and the 401(k) elective deferral limit at $24,500. In exchange for those constraints, dividends and realized gains inside the account generate no annual tax bill.

A taxable brokerage account has no contribution limit, no income limit, and no withdrawal rules. You can put in $80,000 this year and take it all out next Tuesday. The price is that you owe tax as you go — on dividends each year, and on gains when you sell.

What that costs, with the arithmetic

The holding period is where taxable accounts punish impatience. Per IRS Topic 409, an asset held more than one year gets long-term capital gain treatment — currently 0%, 15%, or 20% depending on taxable income, with the thresholds adjusted annually. Held a year or less, the gain is short-term and taxed as ordinary income at your marginal rate.

So on a $10,000 gain, for someone in the 24% bracket:

• Sold at 364 days: $10,000 × 24% = $2,400 in federal tax.
• Sold at 366 days: $10,000 × 15% = $1,500.
• Two days of patience: $900.

State tax may apply on top of both, and higher earners can also face the net investment income tax. Check IRS Topic 409 for the current year's thresholds rather than trusting any article's snapshot, this one included. Our explainer on tax brackets covers why the marginal rate is the one that matters here.

Cash account or margin account — and why the default matters

A cash account means you pay in full for what you buy. A margin account lets you borrow from the broker against your securities to buy more, with interest, using your holdings as collateral.

The SEC's bulletin on opening a brokerage account contains a warning worth repeating: margin may be the default on the new account form. Confirm which one you're signing up for before you sign. Margin amplifies losses as efficiently as it amplifies gains, and if the collateral falls far enough the broker can sell your positions to cover the loan — at the worst possible moment, by definition, because that's when it happens. If you are opening your first brokerage account, there is no version of your situation that requires margin.

The same form will ask about your employment status, annual income, net worth, investment objectives, risk tolerance, investment experience, and time horizon. Those aren't nosy questions for their own sake; they're the record a firm's recommendations get measured against later. Answer them accurately rather than aspirationally.

SIPC: what it covers, and the part people get wrong

Every U.S. broker-dealer registered with the SEC is required to be a SIPC member, and the coverage is real but narrow.

SIPC protects up to $500,000 per customer, with a $250,000 sublimit for cash, if the brokerage firm fails and customer assets are missing. It covers securities held in custody — stocks, bonds, Treasury securities, CDs held at the broker, mutual funds and money market funds, and certain registered investment contracts.

Now the part that gets misunderstood, in SIPC's own framing: SIPC does not bail out investors when the value of their investments falls, for any reason. It is custody insurance, not performance insurance. It also excludes losses from bad or unsuitable investment advice, commodity futures contracts, foreign exchange trades, fixed annuity contracts unless SEC-registered, unregistered investment contracts, currency and stablecoins, and digital assets that aren't registered with the SEC as securities.

In short: if the firm collapses, SIPC is why your shares come back. If the shares themselves drop 40%, SIPC has nothing to say to you.

The cash sweep — where the quiet money is

Uninvested cash in a brokerage account doesn't just sit there. Firms sweep it somewhere every day, and where they sweep it by default is one of the most consequential settings in your account. The SEC's bulletin on cash sweep programs lays out the three destinations:

• A bank sweep, moving your cash into deposit accounts at one or more banks. These are FDIC-insured up to $250,000 per customer per participating bank — and the SEC notes bank sweeps often pay less interest than the alternative.
• A money market fund sweep, moving cash into a fund holding short-term debt like Treasury bills. Not FDIC-insured; covered by SIPC as a security.
• A free credit balance, meaning the cash stays at the firm. The firm may or may not pay you anything on it.

Say you keep $25,000 in cash at a broker. If the default sweep pays 0.35% and a money market option available on the same platform pays 4.00%, that's $87.50 a year versus $1,000 — a $912.50 difference for changing one setting. Rates move constantly, so run it with today's actual numbers, but run it. The SEC is explicit that you can move your uninvested cash in search of a better rate even if the firm enrolled you in its default option automatically.

Two questions to ask your firm, in these words: "Which cash sweep options are available on my account, and what is each one currently paying?" and "Is my sweep FDIC-insured, SIPC-covered, or neither?"

Opening and funding it, in practice

1. Have your Social Security number, government ID, employer name, and bank account and routing numbers ready. The application takes about fifteen minutes.
2. Before you choose a firm, pull its Form CRS relationship summary and check the firm's and any individual's background. The SEC hosts free search tools at Investor.gov.
3. Pick cash, not margin, unless you can articulate a specific reason otherwise.
4. Set the cash sweep deliberately rather than accepting the default.
5. Fund by ACH transfer from your bank. The first transfer often has a hold of a few business days before the money is available to trade.
6. Place the actual investment order. Since May 28, 2024, most U.S. securities trades settle on a T+1 cycle — the shares and the cash officially change hands one business day after the trade, rather than two.
7. Set up automatic recurring investments so step six does not depend on you remembering.

That last step is the one that matters most, because the most common failure mode here isn't a bad investment. It's an account funded once, never invested, and forgotten.

When not to open one

A taxable brokerage account is the wrong next move for a lot of people, and it's usually the one being marketed hardest.

If your employer matches 401(k) contributions and you aren't capturing the full match, every dollar going into a brokerage account instead is skipping an immediate return to chase an uncertain one. If you're carrying a credit card balance north of 20%, paying it down is a guaranteed rate of return that a taxable account cannot promise. If you have no cash reserve, the brokerage account will end up functioning as your emergency fund, which means selling at whatever price the market offers on the day your furnace dies — our guide on where an emergency fund should actually live covers the alternative.

The honest order for most people is: match, then high-interest debt, then a cash cushion, then tax-advantaged space, then the taxable account. If you're already through that list, open it this week and set the recurring transfer before you close the tab.