A cash sweep is an automated transfer that moves uninvested cash out of your brokerage or bank account and into an interest-earning product, usually overnight. When you need the money to buy securities, pay a fee, or make a withdrawal, the sweep reverses and pulls the cash back. Most brokerage firms enroll you in a sweep by default when you open an account, and the destination they pick determines your yield, your insurance protection, and how much the firm earns off your idle balance.
How a Cash Sweep Works Day to Day
Cash lands in your brokerage account from all sorts of sources: a deposit you made, the proceeds of a stock sale, a dividend, a bond coupon. Until you do something with it, that money sits as what the industry calls a “free credit balance.” Under SEC rules, your broker must notify you at least quarterly about any free credit balance and confirm the money is available on demand.1eCFR. 17 CFR 240.15c3-3 – Reserves and Custody of Securities Rather than leaving that cash idle, the sweep program moves it into an interest-bearing product at the end of each business day.
The reverse happens automatically too. Place a buy order in the morning, and the system pulls the necessary amount back into your core account with no delay on your end. You never move cash manually. The sweep is invisible unless you look at your statement and notice which product is listed for your uninvested balance.
Before enrolling you in a sweep, a broker has to get your written consent and give you the terms of the available products. If the broker later changes options or moves 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 buried in the account-opening paperwork most people sign without reading closely.
Where Your Swept Cash Actually Goes
Your uninvested cash generally ends up in one of three places, and many investors never actively choose which. The differences matter, because the gap in yield between the best and worst option can be significant.
Bank Deposit Sweep Programs
A bank sweep moves your cash into one or more FDIC-insured bank deposit accounts. Those banks may be affiliated with your brokerage or part of an outside network. The cash earns interest at a variable rate set by the bank, and that rate is often quite low compared to other options available to you.2Investor.gov. Cash Sweep Programs for Uninvested Cash in Your Investment Accounts – Investor Bulletin
The main advantage is FDIC insurance. Each participating bank in a sweep network insures your deposit up to $250,000 per depositor, per bank, for each ownership category.3FDIC. Understanding Deposit Insurance Large networks split cash across dozens of banks so the entire balance stays within FDIC limits at each one, which lets a network insure balances that would far exceed coverage at any single institution.
Bank sweep is the default at most major brokerages. That default exists partly because it generates reliable revenue for the firm, not necessarily because it offers you the best return.
Money Market Fund Sweeps
A money market fund sweep puts 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, though 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 your statement.4eCFR. 17 CFR 270.2a-7 – Money Market Funds Yields on money market fund sweeps tend to be meaningfully higher than bank sweep rates, especially when short-term rates are elevated. The tradeoff is the lack of FDIC coverage and a small theoretical risk that a fund could “break the buck” and drop below $1.00 per share.
Free Credit Balances
The third option is leaving cash in your brokerage account without sweeping it anywhere. That balance typically earns little or nothing, but it stays immediately available for trading and is covered by SIPC in the event of the brokerage firm’s failure. Investors with very small cash positions or active trading strategies sometimes prefer the simplicity, but for most people it means leaving money on the table.
FDIC Insurance vs. SIPC Protection
The type of protection your swept cash receives depends entirely on where it lands.
Cash swept into a bank deposit program is covered by FDIC insurance up to $250,000 per depositor at each participating bank.3FDIC. Understanding Deposit Insurance The FDIC requires institutions to prominently disclose to sweep account customers whether the swept funds are deposits and what happens if the institution fails.5FDIC. X-6 Sweep Account Disclosure Requirements – FDIC Part 360.8
Cash swept into a money market fund is protected differently. Money market fund shares are securities, so they fall under SIPC coverage rather than FDIC insurance. SIPC steps in when a brokerage firm fails; 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, which includes a $250,000 sublimit specifically for cash claims.2Investor.gov. Cash Sweep Programs for Uninvested Cash in Your Investment Accounts – Investor Bulletin
The practical takeaway: bank sweeps protect you against bank failure with government-backed insurance; money market fund sweeps protect you against brokerage failure but not against investment losses.
Why the Default Often Costs You Money
Here is the part most brokerage marketing skips over. When your cash is swept into a bank deposit program, the bank pays interest on that 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. Across billions in client cash, those fractions of a percent add up. 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 difference between what those firms paid and what comparable sweep programs offered was nearly 400 basis points. In a separate case, FINRA ordered a firm to pay $4.6 million in restitution after finding that 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 is inherently illegal. Brokerages disclose the rates they pay, and sweep accounts are designed as temporary holding places rather than high-yield savings vehicles. But the size of the gap has drawn regulatory scrutiny and class-action lawsuits alleging that firms violated their duty to act in clients’ best interest. On a $100,000 balance, a 3% yield gap is $3,000 a year. Real money, and it compounds.
How to Check and Change Your Sweep
You are not locked into the default. The SEC’s investor education office is blunt 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 are available. Some brokerages offer both a bank deposit sweep and a money market fund sweep. Others only offer one. If none of the in-house options are competitive, you can often buy shares of a money market fund directly within your brokerage account. It just won’t happen automatically through the sweep mechanism.
Worth asking your brokerage:
- What is the current yield on my sweep, and how does it compare to the federal funds rate and to money market funds I could buy directly?
- What other sweep products do you offer? Some firms have multiple options but default customers into the lowest-yielding one.
- Is there a minimum balance to participate or to earn a better tier?
- Is the sweep FDIC-insured or SIPC-protected?
Taxes on Sweep Income
Interest earned in a cash sweep account is taxable in the year it becomes available to you, whether or not you withdraw it. That applies to both bank deposit sweep interest and money market fund dividends. Your brokerage will report the income on a Form 1099-INT or 1099-DIV, but you owe tax on it even if no form is issued.7Internal Revenue Service. Topic No. 403, Interest Received
One exception is worth knowing. Some brokerages offer tax-exempt money market funds as a sweep option. These invest primarily in municipal securities, and the interest is generally exempt from federal income tax, though it may still be subject to state taxes or the alternative minimum tax. Tax-exempt sweep funds typically offer lower pre-tax yields than their taxable counterparts, so whether the tax benefit makes them worthwhile depends on your marginal bracket. Investors in higher brackets tend to benefit most.
A Note on Corporate Cash Sweeps
The term also shows up in a different setting. Corporate treasury departments use cash sweeps to concentrate working capital across dozens or hundreds of bank accounts, typically through a zero-balance account structure that pulls excess funds from subsidiary accounts into a single master account each night and pushes cash back the next morning to cover disbursements. The mechanic is similar to the brokerage version, but the purpose is liquidity management rather than investor yield, and the rules and pricing are different from what applies to your personal account.