A cash sweep is an automated transfer that moves uninvested cash out of your brokerage or bank account at the end of each business day and into an interest-earning product, then pulls it back whenever you need to trade, pay a fee, or withdraw. The point is to keep idle dollars working instead of sitting at zero. Most brokerages enroll you in a sweep program by default when you open an account, and the destination they pick for your cash shapes three things: how much interest you earn, what kind of insurance protects it, and how much revenue the firm makes off your balance.
How a Cash Sweep Works
When money arrives in your brokerage account from a deposit, a stock sale, a dividend, or bond interest, it sits as what the industry calls a “free credit balance.” Under SEC rules, your broker has to notify you at least quarterly that the balance exists and is available on demand.1eCFR. 17 CFR 240.15c3-3 – Reserves and Custody of Securities Rather than leaving the cash idle, the sweep program moves it into an interest-bearing product automatically at day’s end.
The reverse happens just as automatically. Place a buy order, incur a fee, or request a withdrawal, and the system pulls the right amount back into your core account without any action on your part. You never move cash manually. The sweep is invisible unless you look at your statement and notice where your uninvested balance is actually sitting.
Before enrolling you in a sweep, a broker has to get your written consent and provide the general terms of the available products. If the firm later changes sweep options or shifts your cash to a different product, it must give you at least 30 days’ written notice.1eCFR. 17 CFR 240.15c3-3 – Reserves and Custody of Securities In practice, that consent is usually built into the account-opening paperwork most people sign without reading.
Where Your Swept Cash Goes
Uninvested cash generally lands in one of three places, and many investors never actively choose which one.
Bank Deposit Sweep Programs
Bank sweeps move your cash into one or more FDIC-insured bank deposit accounts, which may be affiliated with your brokerage or part of an outside network. The cash earns a variable rate set by the bank, and that rate is often quite low compared to other options.2Investor.gov. Cash Sweep Programs for Uninvested Cash in Your Investment Accounts – Investor Bulletin
The main advantage is FDIC insurance. Each participating bank covers your deposit up to $250,000 per depositor, per bank, for each ownership category.3FDIC. Understanding Deposit Insurance Large deposit networks split your cash across dozens of banks so the full balance stays within FDIC limits at each one, which is how a sweep can insure multi-million-dollar balances that would blow past the limit at a single institution.
Bank sweep is the default at most major brokerages. That default exists partly because it produces reliable revenue for the firm, not necessarily because it offers you the best return.
Money Market Fund Sweeps
A money market fund sweep moves your cash into a mutual fund that invests in short-term, high-quality debt: Treasury bills, government agency securities, commercial paper, and similar instruments. These funds pay dividends that track short-term interest rates and are generally considered low-risk. They are not bank deposits and carry no FDIC insurance.2Investor.gov. Cash Sweep Programs for Uninvested Cash in Your Investment Accounts – Investor Bulletin
Government and retail money market funds are allowed to maintain a stable share price of $1.00, which is why your balance looks like plain cash on a statement.4eCFR. 17 CFR 270.2a-7 – Money Market Funds Yields on money market fund sweeps are often meaningfully higher than bank sweep rates, especially when short-term rates are elevated. The tradeoff is the absence of FDIC coverage and a small theoretical risk that a fund could “break the buck,” meaning its share price drops below $1.00.
Free Credit Balances
The third option is leaving cash in your brokerage account without sweeping it anywhere. It typically earns little or nothing but is immediately available for trading and is protected by SIPC if the brokerage fails. Some investors with small balances or very active strategies prefer the simplicity. For most people it means leaving money on the table.
FDIC Insurance Versus SIPC Protection
What protects your swept cash depends entirely on where the sweep sends it, and the two systems do different jobs.
Cash in a bank deposit sweep is covered by FDIC insurance up to $250,000 per depositor at each participating bank.3FDIC. Understanding Deposit Insurance If a bank in the network fails, your insured deposits are covered dollar for dollar. The FDIC requires institutions to disclose prominently whether swept funds are deposits and what happens to them if the institution fails.5FDIC. X-6 Sweep Account Disclosure Requirements – FDIC Part 360.8
Cash in a money market fund sweep gets different protection. Money market fund shares are securities, so they fall under SIPC rather than FDIC. SIPC protects customers when a brokerage firm fails financially; it does not protect against a decline in the value of your investments.6Securities Investor Protection Corporation. What SIPC Protects The coverage limit is $500,000 per customer, with a $250,000 sublimit specifically for cash claims.2Investor.gov. Cash Sweep Programs for Uninvested Cash in Your Investment Accounts – Investor Bulletin If a money market fund itself loses value, SIPC does not cover that loss. It steps in only if the brokerage holding your shares goes under and your assets are missing.
The practical read: bank sweeps protect against bank failure with government-backed insurance; money market fund sweeps protect against brokerage failure but not against investment losses.
Why Your Sweep Rate Matters
Here is the part most brokerage marketing skips. When your cash is swept into a bank deposit program, the bank pays interest on the deposit. The rate the bank pays and the rate you receive are not the same number. The brokerage keeps the difference as revenue, and the difference can be large.
As of early 2026, the federal funds rate sat around 3.64%, yet one major wirehouse was paying bank sweep customers as little as 0.02% on balances under $1 million. That is a spread of more than 350 basis points on every dollar. The SEC penalized two major broker-dealers in January 2025, fining one $35 million and the other $25 million, for failing to pay advisory clients appropriate interest on swept cash. The gap between what those firms paid and what comparable sweep programs offered was nearly 400 basis points. FINRA has also acted: in one case, it ordered a firm to pay $4.6 million in restitution after finding the firm calculated sweep fees differently than its own disclosures described, keeping over $3 million in excess charges over a four-year period.
None of this makes a low sweep rate illegal on its own. Brokerages disclose their rates, and sweep accounts are designed as temporary holding places rather than high-yield savings vehicles. But on a $100,000 cash balance, a 3% spread is $3,000 a year.
How to Check or Change Your Sweep
You are not locked into whatever your firm chose for you. The SEC’s investor education office is direct about this: you can move your uninvested cash in search of higher rates even if the firm automatically enrolled you in its default program.2Investor.gov. Cash Sweep Programs for Uninvested Cash in Your Investment Accounts – Investor Bulletin
Start with your most recent account statement. It should list where your uninvested cash is held and the current interest or dividend rate. Then ask your firm what other sweep options exist. Some brokerages offer both a bank sweep and a money market fund sweep. Others offer only one. If none of the in-house options are competitive, you can usually buy shares of a money market fund directly within your brokerage account; it just won’t happen automatically through the sweep.
Questions worth asking:
- What is the current yield on my sweep, and how does it compare to the federal funds rate or to money market funds I could buy directly?
- Are other sweep products available at this firm?
- Is there a minimum balance required to participate or to earn a better rate?
- Is the sweep FDIC-insured or SIPC-protected?
Taxes on Sweep Income
Interest earned in a cash sweep is taxable income in the year it becomes available to you, whether you withdraw it or not. This applies to bank deposit sweep interest and to money market fund dividends. Your brokerage will report the income on a Form 1099-INT or 1099-DIV, but the tax is owed even if no form is issued.7Internal Revenue Service. Topic No. 403, Interest Received
One exception: some brokerages offer tax-exempt money market funds as a sweep option. These funds invest primarily in municipal securities, and the interest is generally exempt from federal income tax, though it may still be subject to state tax or the alternative minimum tax. Tax-exempt sweep funds usually offer lower pre-tax yields than their taxable counterparts, so whether the tax benefit is worth it depends on your marginal bracket.
Cash Sweeps for Businesses
The term “cash sweep” also describes something different in corporate finance, so it’s worth flagging if that is what brought you here. Corporate treasury departments use sweeps to consolidate working capital across many bank accounts.
The most common structure is a zero-balance account arrangement. A company sets up subsidiary accounts for individual stores, regional offices, or plants, along with a single master concentration account. At the end of each business day, the sweep moves excess cash from every subsidiary account into the master account. If a subsidiary needs funds the next morning for disbursements, the sweep moves cash back in. Subsidiary accounts end the day at a target balance, often zero, and the master account holds the consolidated total where the treasury team can invest it overnight or use it to pay down a credit line.
The economics are simple. Fifty million dollars scattered across 200 accounts in small balances earns almost nothing. The same $50 million concentrated into a single overnight investment earns meaningful interest and gives the treasurer a clear picture of liquidity. Corporate sweep services typically cost between $25 and $300 per month depending on transaction volume and the number of linked accounts.