Wealthy PotSGOV vs SPAXX (2026)
This is not a like-for-like comparison and the difference matters. SPAXX is a money-market fund with a stable $1.00 share price that sweeps automatically at Fidelity. SGOV is an exchange-traded fund holding 0-3 month T-bills: you place an order, the price floats around $100, and settlement takes a day. What you buy with that friction is cost and tax treatment — 0.09% against 0.42%, and almost pure Treasury income that is generally exempt from state and local tax. In a taxable account in a high-tax state, SGOV usually wins after tax. In an IRA, or for cash you might need tomorrow, SPAXX’s simplicity is worth more than the spread.
By Wealthy Pot · Last updated September 2026
| Feature | SGOV | SPAXX |
|---|---|---|
| Provider | iShares (BlackRock) | Fidelity |
| Wrapper | Exchange-traded fund | Money-market fund |
| Holdings type | Treasury | Government |
| Yield (SEC) | 3.65% (30-day SEC yield, 2026-09-17) | 3.34% (7-day SEC yield) |
| Share price | Floating share price (~$100), not a stable $1.00 NAV | Stable $1.00 NAV (targeted, not guaranteed) |
| Expense ratio | 0.09% | 0.42% |
| Minimum | One share (about $100) | $0 |
| State tax | Holds only short-dated U.S. Treasury bills, so nearly all income is typically exempt from state and local tax | Partly state-tax-exempt (50.9% U.S. government obligations, 2025 — below the CA/CT/NY threshold) |
| Auto-sweep? | No — an exchange-traded fund you buy and sell yourself; it can never be an automatic core position | Yes — a default core/sweep position at Fidelity |
| Best for | Taxable investors in high-tax states who will park cash for a while and do not need instant sweep access | Fidelity customers who want their idle cash to earn a yield automatically |
Where SGOV wins
- A 0.09% expense ratio and almost pure T-bill income, which is the most state-tax-efficient way to hold cash
Where SPAXX wins
- The default Fidelity core/sweep position — idle cash earns automatically
- No minimum investment
- Government fund (holds government debt and repos), lower credit risk than prime
- Portion of income is state-tax-exempt
Which should you choose?
This is not a like-for-like comparison and the difference matters. SPAXX is a money-market fund with a stable $1.00 share price that sweeps automatically at Fidelity. SGOV is an exchange-traded fund holding 0-3 month T-bills: you place an order, the price floats around $100, and settlement takes a day. What you buy with that friction is cost and tax treatment — 0.09% against 0.42%, and almost pure Treasury income that is generally exempt from state and local tax. In a taxable account in a high-tax state, SGOV usually wins after tax. In an IRA, or for cash you might need tomorrow, SPAXX’s simplicity is worth more than the spread.
Compare these against every fund in our money-market fund comparison.
We summarize the funds' published facts, not user reviews. Yields are variable, change daily, and are re-checked against each fund's official page. Neither money-market funds nor ETFs are FDIC-insured, and an ETF's share price can fall as well as rise. Some outbound links may be affiliate links — that never affects our comparisons. Nothing here is financial advice.