In a brokerage account, the cash and sweep vehicle is the automatic arrangement your broker uses to move any uninvested money in your account into a product that earns a return, usually a money market fund or a bank deposit account at one or more partner banks. “Cash” is the idle money left over after trades settle, dividends land, or you make a deposit. The “sweep vehicle” is where that idle money goes each day so it isn’t sitting dormant. The transfer happens overnight without any action on your part, but the interest rate you receive, the insurance protecting your balance, and the cut your broker keeps all depend on which sweep vehicle your account uses.
How the Daily Sweep Works
At the end of each business day, your broker’s system checks your account for any cash that isn’t needed to cover pending trades or other obligations. Common events that create a cash surplus include a stock sale settling, a dividend payment arriving, or a new deposit clearing. Any surplus gets transferred automatically to the designated sweep vehicle during overnight processing, where it begins earning interest or dividends.
When you need the money back, the system reverses the process. Place a trade, request a withdrawal, or write a check against the account, and funds are pulled from the sweep vehicle to cover the obligation. You generally don’t experience a delay. Your broker displays the swept balance as part of your available buying power, so you can act on it immediately during market hours.
Over weekends and bank holidays the timing stretches. Funds identified as eligible for sweeping on a Friday afternoon may not actually reach the sweep vehicle until Monday or Tuesday. During that gap the cash may not earn interest, and if the sweep vehicle is a bank deposit account, it may not yet qualify for FDIC insurance.
Types of Sweep Vehicles
Your broker selects one or more sweep vehicles for your account. Each type carries different trade-offs in yield, insurance, and tax treatment.
Money Market Mutual Funds
Money market mutual funds are the traditional sweep vehicle, governed by SEC Rule 2a-7, which imposes strict rules to keep these funds low-risk and highly liquid. Government money market funds and retail money market funds can maintain a stable share price of $1.00, which makes them feel similar to a bank account. Institutional prime and institutional tax-exempt money market funds must use a floating net asset value that reflects the market value of their holdings.1SEC.gov. Final Rule: Money Market Fund Reforms
Some brokerages have moved away from offering money market funds as the default, sending cash to bank deposit programs instead. If a money market sweep is available at your broker, it may offer a higher yield than the bank deposit alternative, but you may need to actively select it.
Bank Deposit Sweep Programs
In a bank deposit sweep, your broker moves your uninvested cash into interest-bearing deposit accounts at one or more partner banks.2Investor.gov. Investor Bulletin: Bank Sweep Programs You still manage everything through your brokerage platform; the deposits at the partner banks happen behind the scenes. Many programs spread your balance across a network of banks, placing up to $250,000 at each one to keep the entire amount within FDIC insurance limits. A program using ten partner banks could provide up to $2.5 million in aggregate FDIC coverage.
Treasury and Municipal Options
Some brokers offer money market funds that invest exclusively or primarily in U.S. Treasury securities. Interest from these funds is subject to federal income tax but is generally exempt from state and local income taxes in most states, which can help if you live in a high-tax state. A handful of brokers also offer municipal money market funds, which invest in short-term debt issued by state and local governments. Dividends from these funds are generally exempt from federal income tax, and in some cases from the issuing state’s income tax as well. Municipal money market funds are available only to individual investors, not institutions.
How Your Swept Cash Is Insured
The type of insurance covering your swept cash depends entirely on which vehicle holds it. SIPC and FDIC protect against different risks and have different limits.
If your sweep vehicle is a money market mutual fund, your protection comes from the Securities Investor Protection Corporation. SIPC covers up to $500,000 per customer if your brokerage firm fails, with a $250,000 sub-limit on claims for cash.3Office of the Law Revision Counsel. 15 USC Chapter 2B-1 – Securities Investor Protection SIPC classifies money market mutual fund shares as securities, not cash, so they count against the higher $500,000 securities limit rather than the $250,000 cash cap.4SIPC. How SIPC Protects You SIPC does not protect against investment losses. It only steps in when a brokerage firm becomes insolvent and customer assets are missing.
When your cash is swept into bank deposit accounts, it falls under FDIC insurance instead. Each partner bank in the sweep network insures your deposits up to $250,000, and deposits at separately chartered banks are insured independently of each other.5GovInfo. 12 CFR Part 330 – Deposit Insurance Coverage If one bank in the network fails, your deposits at the remaining banks are unaffected.
One trap to watch. If you already hold deposits at one of the partner banks in your own name, a savings account you opened directly, for example, those balances are combined with your swept deposits for purposes of the $250,000 cap at that particular bank. Check the list of partner banks in your sweep program disclosure to avoid unintentional overlaps.
What Your Broker Keeps
One of the least visible costs in a brokerage account is the spread your broker earns on your swept cash. Most brokers keep a portion of the interest paid by the partner banks or money market funds before passing the remainder to you.2Investor.gov. Investor Bulletin: Bank Sweep Programs In a higher-rate environment, the gap between what the sweep vehicle earns and what you actually receive can be substantial, sometimes as much as 4 to 5 percentage points.6FINRA. Don’t Lose Interest: Managing Cash in Your Brokerage Account
This spread has drawn regulatory scrutiny. In January 2025, the SEC charged Wells Fargo advisory firms and Merrill Lynch with failing to adopt policies that considered the best interests of their clients when selecting sweep program options. During periods of rising interest rates, the yield gap between these firms’ bank deposit sweeps and other available alternatives grew to almost 4 percent. The firms agreed to pay a combined $60 million in civil penalties.7SEC.gov. SEC Charges Pair of Wells Fargo Advisory Firms and Merrill Lynch
The dollar effect adds up. If you hold $50,000 in a sweep account paying 0.25 percent while a high-yield savings account or directly purchased money market fund pays 4 percent, you’re giving up roughly $1,875 per year in potential interest. The convenience of automatic sweeping is real, but it has a cost worth understanding.
How Sweep Income Is Taxed
Any interest or dividends your sweep vehicle earns is taxable income in the year you receive it, whether you withdraw the money or leave it in the account. Interest from bank deposit sweeps is reported on Form 1099-INT, which your broker or the partner bank issues if you earned at least $10 in interest during the year.8Internal Revenue Service. About Form 1099-INT, Interest Income Distributions from money market mutual funds, even though they function like interest, are technically classified as dividends and reported on Form 1099-DIV.9Internal Revenue Service. About Form 1099-DIV, Dividends and Distributions Either way, the income is taxed at ordinary income rates, not at the lower qualified dividend or capital gains rates.
If you haven’t provided a valid taxpayer identification number to your broker, or the IRS has flagged you for underreporting interest or dividends, your broker must withhold tax at a flat 24 percent rate on your sweep earnings. This is known as backup withholding, and it applies until the issue is resolved.10Internal Revenue Service. Topic No. 307, Backup Withholding The withheld amount counts as a prepayment of your taxes; you claim credit for it when you file your return.
Your Rights and How to Change Your Sweep Vehicle
Federal rules require your broker to get your written consent before enrolling your cash in a sweep program. The broker must provide you with the general terms and conditions of available sweep products and obtain your affirmative agreement before sweeping begins. Your broker must also send you a statement at least once every three months showing the amount held for your account and confirming that the funds are payable on demand.11eCFR. 17 CFR 240.15c3-3 Customer Protection – Reserves and Custody of Securities
If your broker offers more than one sweep option, you can typically switch by contacting your financial advisor or the firm’s client services team. Not every broker offers a choice. Some default all accounts to a bank deposit sweep with no money market alternative. Before opening an account, check the sweep program disclosure (usually available on the firm’s website) to see what options exist, what rate you’ll earn, and how much the firm keeps. If the default sweep rate is significantly below market rates, you may be better off periodically moving excess cash into a higher-yielding money market fund or savings account on your own.