Vanguard Announces New Treasury Bill ETFs: New Best Cash Alternative?

Vanguard recently released an announcement that in “First Quarter 2025” they will be releasing two new index ETFs that both hold short-term US Treasury Bonds:

Vanguard 0-3 Month Treasury Bill ETF (VBIL). Holds Treasuries with maturities of 3 months or less. Estimated expense ratio of 0.07%.
Vanguard Ultra-Short Treasury ETF (VGUS). Holds Treasuries with maturities of less than 12 months. Estimated expense ratio of 0.07%.

Currently, I would say the two best options for those who want low-cost exposure to Treasury Bills as a cash alternative without having to manually manage their own T-Bill ladder are:

iShares 0-3 Month Treasury Bond ETF (SGOV). Holds Treasuries with maturities of 3 months or less (1.2 months weighted average as of 12/2024). Expense ratio of 0.09%. 30-day historical median bid/ask spread of 0.01%. Can be bought and sold at nearly any brokerage.
Vanguard Treasury Money Market Fund (VUSXX). Maintains a NAV of $1. Holds Treasuries with average maturity of 38 days (as of 10/31/24). Expense ratio of 0.09%. Usually must be bought and sold within a Vanguard brokerage accounts to avoid transaction fees.

The advantages of owning properly-managed T-Bill funds are that you hopefully maintain the state income tax exemption of T-Bill interest, while adding the convenience and easy liquidity of ETFs and mutual funds. T-Bills often give residents of states with high local/state income taxes the highest tax-equivalent yield available for a cash equivalent (minimal volatility, minimal principal risk).

For tax year 2023, SGOV reported 96.45% of interest was derived from qualified U.S. Government and agency obligations. In many states, this meant that 96.45% of the interest paid out was exempt from state and local income taxes.

For tax year 2023, VUSXX reported 80.06% of interest was derived from qualified U.S. Government and agency obligations. In many states, this means that 80.06% of the interest paid out was exempt from state and local income taxes.

Ideally, VBIL will be very similar to SGOV with a tight bid/ask spread and nearly all interest eligible for state income tax exemption, but with even lower expenses and thus higher net yields. Something to keep a look out for in early 2025.