SGOV vs VUSXX vs HYSA: Which Is Better for Your Cash?

If you're trying to earn a decent return on cash without taking real risk, the same three names keep coming up: a high-yield savings account (HYSA) at a bank, SGOV (an ETF holding ultra-short U.S. Treasury bills), and VUSXX (Vanguard's Treasury money market fund).

So which wins? Honestly, it's rarely about the headline yield. The decision comes down to after-tax return, how fast you can actually get your money, and what can go wrong - even if the odds are small.

Quick Definitions (So We're Comparing the Right Things)

HYSA (High-Yield Savings Account)

A savings account at a bank or credit union that pays a competitive rate. It's typically FDIC (banks) or NCUA (credit unions) insured up to $250,000 per depositor, per institution. The interest is usually taxed as ordinary income federally and, in most states, at the state level too. The appeal is simplicity: set it and forget it.

SGOV (Treasury Bill ETF)

SGOV is an exchange-traded fund that holds very short-term U.S. Treasury bills. You buy and sell it like a stock in a brokerage account, and it pays distributions, usually monthly. It's not "insured" the way a bank account is - instead, it's backed by the credit of the U.S. government through the T-bills it holds.

VUSXX (Treasury Money Market Fund)

VUSXX is a money market mutual fund focused on U.S. Treasury securities. It aims to hold a stable $1 share price (though it's not a bank deposit) and is built for cash management inside a brokerage. Distributions are typically ordinary income for tax purposes, with potential state-tax benefits depending on what the fund held during the year.

The Big Differentiator: Taxes (Especially State Taxes)

If you live in a state with income tax, this is often what decides it.

HYSA taxes: simple, but fully taxable

HYSA interest is generally taxable as ordinary income at the federal level and in most states at the state level. Your after-tax yield can end up meaningfully lower than the advertised APY.

SGOV taxes: often state-tax advantaged

U.S. Treasury interest is federally taxable as ordinary income, but it's often exempt from state and local tax. Since SGOV's income comes from T-bills, a portion - often most - of its distributions may escape state and local income tax entirely. The exact exempt percentage varies year to year, so check the fund's annual tax information.

VUSXX taxes: often partially state-tax advantaged

Same idea. VUSXX's Treasury focus can create state-tax advantages, but the exempt portion depends on what the fund actually held during the year (Treasuries vs. repurchase agreements and other instruments).

The practical takeaway: in a high-tax state, Treasury-based options can beat an HYSA on after-tax yield even when the pre-tax numbers look similar.

Safety and "What Can Go Wrong?"

All three are low risk - but low risk in different ways.

HYSA: strongest protection against loss of principal (within limits)

If your priority is "I never want to see this balance go down," FDIC/NCUA insurance is hard to beat. You still technically have bank risk, but insurance exists to cover exactly that, up to the limits.

SGOV: very low interest-rate risk, but it can fluctuate

SGOV is an ETF, so the price moves slightly day to day. Sell at a different price than you bought and you'll have a small capital gain or loss. In stressed markets you're also exposed to bid/ask spreads and market liquidity - usually a non-issue for a cash ETF this large, but it's not the same experience as a bank balance.

VUSXX: designed for stability, but not a bank account

Money market funds are built for cash-like stability, but they aren't FDIC insured. In rare, extreme market stress, money market funds can face restrictions like fees or redemption gates, depending on fund structure and rules. Uncommon, but part of the true risk picture.

Access to Your Money (Liquidity in Real Life)

When you call something an "emergency fund," what you really mean is: how fast can I pay for an emergency?

An HYSA is usually excellent here, though ACH transfers can take 1-3 business days. Some banks offer same-day or instant transfers; it varies.

With SGOV, you can sell any day the market is open, but cash availability depends on your broker's settlement rules - often T+1 for U.S. equities and ETFs. Fine if your emergency timeline is "within a day or two," less ideal if you need cash this minute.

VUSXX trades once per day like any mutual fund, and proceeds are typically available the next business day, depending on the brokerage.

A setup many people land on: keep a smaller, immediate-access buffer in checking or an HYSA, and park the rest of the short-term cash in whichever option wins after tax.

Costs, Minimums, and Details People Miss

None of these are dealbreakers, but they can tip the scales.

Expenses. An HYSA has no explicit expense ratio, but the bank sets the rate and can change it anytime. SGOV has an ETF expense ratio that slightly trims your net return, and VUSXX has one too (usually already reflected in the quoted yield).

Minimums and availability. Some money market funds have minimum investments or aren't offered at every brokerage. SGOV is generally easy to buy anywhere you can trade ETFs.

FDIC/NCUA vs SIPC - important distinction. FDIC/NCUA insurance protects your bank deposit up to the limits. SIPC is different: it protects against broker failure (missing securities or cash), not against market losses or a fund declining in value.

Tax paperwork. HYSA interest is straightforward - usually a 1099-INT. SGOV involves brokerage reporting (1099-DIV, plus potentially a 1099-B if you sell). VUSXX typically shows up on a 1099-DIV, and you figure the state-tax-exempt percentage from the fund's year-end tax information.

Which One Wins Depends on Your Use Case

Choose an HYSA if you want maximum simplicity plus insurance

Hard to beat when you care most about FDIC/NCUA coverage, simple access, a stable balance, and not dealing with brokerage mechanics or 1099-B nuances.

Choose SGOV if you want state-tax advantages and brokerage flexibility

Makes sense when you're in a higher-tax state and want to maximize after-tax yield, you're comfortable holding cash at a brokerage, and small price fluctuations don't bother you.

Choose VUSXX if you want a cash-like fund inside a brokerage

A strong fit if you already use Vanguard (or your brokerage offers the fund), you prefer money-market mechanics - the stable NAV goal - over ETF pricing, and you value the potential state-tax advantages of Treasury-heavy income.

A Simple Decision Checklist

Is this money truly for emergencies (same-day access)? Lean HYSA/checking for at least a portion.
Do you live in a state with meaningful income tax? Treasury-heavy options (SGOV/VUSXX) may win after tax.
Do you hate complexity? HYSA is the cleanest.
Do you already keep cash in a brokerage account? VUSXX or SGOV can slot right in.
Do small fluctuations in value bother you? An HYSA or money market fund will feel more stable than an ETF.

Where I'd Land

For most savers, the answer is a blend: an HYSA for immediate access and peace of mind, plus SGOV or VUSXX for the chunk of cash where you're optimizing after-tax yield - especially if state taxes bite.

And if you want to keep it dead simple? Start with an HYSA. Graduate to SGOV or VUSXX once you're confident you're fine with the mechanics and the small tradeoffs.