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

If you’re trying to earn a solid return on cash without taking big risks, you’ll keep hearing the same three options:

A high-yield savings account (HYSA) at a bank
SGOV (an ETF that holds ultra-short U.S. Treasury bills)
VUSXX (Vanguard’s Treasury money market fund)

So… which is better?

For many people, the “best” choice isn’t about the headline yield. It’s about after-tax return, how fast you can get your money, and what can go wrong (even if the risk is small).

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

HYSA (High-Yield Savings Account)

A bank (or credit union) savings account that pays a competitive rate.

Typically FDIC (banks) or NCUA (credit unions) insured up to $250,000 per depositor, per institution
Interest is usually taxed as ordinary income at the federal level and (in most states) the state level
Great for simple, set-it-and-forget-it cash

SGOV (Treasury Bill ETF)

SGOV is an exchange-traded fund that holds very short-term U.S. Treasury bills.

You buy/sell it like a stock in a brokerage account
It pays distributions (often monthly)
It’s not “insured” like a bank account, but it’s backed by the credit of the U.S. government through the underlying T-bills

VUSXX (Treasury Money Market Fund)

VUSXX is a money market mutual fund that focuses on U.S. Treasury securities.

It aims to keep a stable $1 share price (though it’s not a bank deposit)
It’s designed for cash management inside a brokerage
Distributions are typically treated as ordinary income for taxes, 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, taxes can be the deciding factor.

HYSA taxes (simple, but fully taxable)

HYSA interest is generally:

Federal: taxable as ordinary income
State/local: taxable in most states

That means your after-tax yield can be meaningfully lower than the advertised APY.

SGOV taxes (often state-tax advantaged)

U.S. Treasury interest is generally:

Federal: taxable as ordinary income
State/local: often exempt

Because SGOV’s income comes from Treasury bills, a portion (often most) of its distributions may be exempt from state and local income tax. The exact exempt percentage can vary year to year, so it’s worth checking the fund’s annual tax information.

VUSXX taxes (often partially state-tax advantaged)

VUSXX focuses on Treasuries, which can also create state-tax advantages. But the exact state-tax-exempt portion depends on what the fund held (Treasuries vs. repurchase agreements and other instruments) during the year.

Practical takeaway:

In a high-tax state, Treasury-based options can have a higher after-tax yield even if the pre-tax yield looks similar.

Safety and “What Can Go Wrong?”

All three options are low risk, but they’re low risk in different ways.

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

FDIC/NCUA insurance is a big deal if you’re optimizing for “I never want to see this balance go down.”
You still have bank risk, but insurance is designed to cover that up to the limits.

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

Because SGOV is an ETF:

The price can move slightly day to day
You can have a small capital gain or loss if you sell at a different price than you bought
In stressed markets, you’re exposed to bid/ask spreads and market liquidity (usually minor for a large cash ETF, 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 are not FDIC insured
In rare, extreme market stress, money market funds can face restrictions (like fees or redemption gates), depending on fund structure and rules

These scenarios are uncommon, but they’re part of the true risk profile.

Access to Your Money (Liquidity in Real Life)

When you say “this is my emergency fund,” what you really mean is: how fast can I pay for an emergency?

HYSA liquidity

Typically excellent for ACH transfers, but transfers can take 1–3 business days
Some banks offer same-day or instant transfers, but it varies

SGOV liquidity

You can sell any market day when the market is open
Cash availability depends on your broker’s settlement rules (often T+1 for U.S. equities/ETFs)
Great if your emergency timeline is “within a day or two,” less ideal if you need cash this minute

VUSXX liquidity

Usually trades once per day (mutual fund mechanics)
Proceeds are typically available on the next business day (varies by brokerage)

Practical approach many people use:

Keep a smaller, immediate-access cash buffer in a checking/HYSA
Keep the rest of the short-term cash in the higher after-tax option (SGOV/VUSXX), if it fits your situation

Costs, Minimums, and Account Details People Miss

These aren’t dealbreakers, but they can change what’s “better” for you.

Expenses

HYSA: usually no explicit expense ratio, but the bank sets the rate (and can change it anytime).
SGOV: ETFs typically have an expense ratio that slightly reduces your net return.
VUSXX: money market funds also have an expense ratio (often reflected in the quoted yield).

Minimums and availability

Some money market funds have minimum investments or may not be available at every brokerage.
ETFs like SGOV are generally easy to buy anywhere you can trade ETFs (subject to broker rules).

FDIC/NCUA vs SIPC (important distinction)

FDIC/NCUA (bank/credit union insurance) is designed to protect your deposit up to limits.
SIPC (brokerage protection) is different: it generally protects against broker failure (missing securities/cash), not against market losses or a fund declining in value.

Tax paperwork

HYSA interest is typically straightforward (often a 1099-INT).
SGOV can involve brokerage reporting (like 1099-DIV, and potentially 1099-B if you sell).
VUSXX is typically reported on a 1099-DIV, and the state-tax-exempt percentage (if any) is usually something you determine from the fund’s year-end tax information.

Which One Is “Better” Depends on Your Use Case

Choose an HYSA if you want maximum simplicity + insurance

An HYSA is hard to beat when you care most about:

FDIC/NCUA insurance
Simple access and stable balance
Not dealing with brokerage mechanics or 1099-B nuances

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

SGOV can make sense when:

You’re in a higher-tax state and want to maximize after-tax yield
You’re comfortable holding cash in a brokerage
You don’t mind small price fluctuations

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

VUSXX can be a strong fit when:

You already use Vanguard (or have access to the fund at your brokerage)
You want money-market mechanics (stable NAV goal) instead of ETF pricing
You value the potential state-tax advantages of Treasury-heavy income

A Simple Decision Checklist

If you want the quick answer, here’s a practical way to decide:

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 on after-tax yield.
Do you hate complexity?
- HYSA is the cleanest.
Do you already keep cash in a brokerage account?
- VUSXX (money market) or SGOV (ETF) can integrate nicely.
Do small fluctuations in value bother you?
- HYSA or a money market fund may “feel” more stable than an ETF.

Final Thoughts

For many savers, the best setup is a blend:

HYSA for immediate access + peace of mind
SGOV or VUSXX for the portion of cash where you’re optimizing after-tax yield (especially if state taxes matter)

If you want to keep it simple: start with an HYSA, and only graduate to SGOV/VUSXX when you’re confident you’ll be comfortable with the mechanics and the small tradeoffs.