Updated October 23, 2026 from live rates
Where to keep $5 million in cash
At today's rates, $5 million in a default brokerage sweep paying 0.01% earns about $290 a year after tax. The best option we track keeps about $139,860, $139,570 more, assuming the 37% federal bracket and 5% state tax.
The best option of each kind, after tax
37% federal bracket, 5% state tax, today's rates, $5 million. Your numbers will differ; the comparison page uses your own.
| Option | Rate | Kept after tax, per year | Getting your money | Protection |
|---|---|---|---|---|
| 1-year Treasury billBought at auction or in your brokerage, held to maturity | 4.44%Verified October 23, 2026 | $139,860 | Matures in 12 months; can be sold any day at market price | Backed by the U.S. government |
| Treasury-only money fundFSIXX, Fidelity Treasury Only Portfolio, on Merrill | 3.79%Verified October 20, 2026 | $119,385 | Next business day | Money market fund, not FDIC-insured |
| Vanguard brokerageVMFXX, Vanguard Federal Money Market (settlement fund) | 3.83%Verified October 21, 2026 | $117,448 | Same day | Money market fund, not FDIC-insured |
| Wealthfront Cash AccountHigh-yield savings | 3.55%Verified October 23, 2026 | $102,950 | 1 to 2 business days to move | FDIC: Up to $8M through program banks |
| For comparison: a typical default sweepMerrill EdgeMerrill Lynch Bank Deposit Program | 0.01%Verified October 20, 2026 | $290 | Same day | FDIC-insured at Bank of America (limits apply) |
Three things that matter at this size
- Insurance limits. FDIC insurance covers $250,000 per depositor, per bank, per ownership category. At $5 million, keeping it all insured in plain bank accounts takes about 20 banks, or a program that spreads deposits across banks, or Treasuries, which are backed by the U.S. government. Check your coverage.
- State tax. Treasury bills and Treasury-only funds avoid state income tax, which is worth more the higher your state rate. T-bills vs money market funds.
- When you'll need it. Money you may need this week belongs where it moves same day; the best of those today is Treasury-only money fund. Money you won't touch for months can go into Treasury bills, whose rate is fixed until they mature. Build a Treasury ladder.
Cash intelligence
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