FMUB vs. ZMUN

Last updated Aug 6, 2026

FMUB (Fidelity Municipal Bond Opportunities ETF) and ZMUN (F/m Ultrashort Tax-Free Municipal ETF) are both Municipal Bonds funds. FMUB is actively managed, while ZMUN is passively managed. Their 0.26 correlation means their historical movements had little consistent relationship. Both charge a 0.30% expense ratio.

Performance

FMUB vs. ZMUN - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Municipal Bond Opportunities ETF (FMUB) and F/m Ultrashort Tax-Free Municipal ETF (ZMUN). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FMUB achieves a 1.70% return, which is significantly lower than ZMUN's 2.09% return.

FMUB

• 1D: 0.31%
• 1M: -0.83%
• 6M: 1.01%
• YTD: 1.70%
• 1Y: 5.57%
• 3Y*: —
• 5Y*: —
• 10Y*: —
• ALL TIME*: 4.83%

ZMUN

• 1D: 0.01%
• 1M: 0.23%
• 6M: 1.81%
• YTD: 2.09%
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —
• ALL TIME*: —

*Multi-year figures are annualized to reflect compound growth (CAGR)

Liquidity Comparison

Position	Avg. Volume Value (2W)	Avg. Volume Value (1M)	Avg. Volume Value (3M)
FMUB Fidelity Municipal Bond Opportunities ETF	$1.88M	$2.46M	$1.66M
ZMUN F/m Ultrashort Tax-Free Municipal ETF	$209.92K	$243.19K	$389.33K

FMUB vs. ZMUN - Yearly Performance Comparison

	2026 (YTD)	2025
FMUB Fidelity Municipal Bond Opportunities ETF	1.70%	1.29%
ZMUN F/m Ultrashort Tax-Free Municipal ETF	2.09%	0.67%

Correlation

The correlation between FMUB and ZMUN is 0.26, which is low. Their historical price movements had little consistent relationship.

	Correlation
Correlation (All Time) Calculated using the full available price history since Sep 30, 2025	0.26

Return for Risk

FMUB vs. ZMUN — Risk / Return Rank

Compare historical risk-adjusted metric ranks over the past 12 months.

FMUB

FMUB Risk / Return Rank: 72
FMUB Sharpe Ratio Rank: 80
FMUB Sortino Ratio Rank: 79
FMUB Omega Ratio Rank: 87
FMUB Calmar Ratio Rank: 55
FMUB Martin Ratio Rank: 60

ZMUN

Risk / return metrics aren't available yet — we need at least 12 months of trading data to calculate them.

The rank (0–100) uses a weighted average of the Sharpe, Sortino, Omega, Calmar, and Martin percentile ranks for the trailing 12 months. Higher means stronger historical risk-adjusted performance within the peer group.

FMUB vs. ZMUN - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Municipal Bond Opportunities ETF (FMUB) and F/m Ultrashort Tax-Free Municipal ETF (ZMUN). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	FMUB	ZMUN	Difference
Sharpe ratio: Return per unit of total volatility	2.06	—	—
Sortino ratio: Return per unit of downside risk	2.88	—	—
Omega ratio: Gain probability vs. loss probability	1.42	—	—
Calmar ratio: Return relative to maximum drawdown	2.24	—	—
Martin ratio: Return relative to average drawdown	8.13	—	—

Drawdowns

FMUB vs. ZMUN - Drawdown Comparison

The maximum FMUB drawdown since its inception was -2.74%, which is greater than ZMUN's maximum drawdown of -0.13%. Use the drawdown chart below to compare losses from any high point for FMUB and ZMUN.

Drawdown Indicators

	FMUB	ZMUN	Difference
Max Drawdown Largest peak-to-trough decline	-2.74%	-0.13%	-2.61%
Max Drawdown (1Y) Largest decline over 1 year	-2.49%	—	—
Current Drawdown Current decline from peak	-0.88%	0.00%	-0.88%
Average Drawdown Average peak-to-trough decline	-0.49%	-0.02%	-0.47%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.69%	—	—

Volatility

Volatility by Period

	FMUB	ZMUN	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.03%	—	—
Volatility (6M) Calculated over the trailing 6-month period	2.23%	—	—
Volatility (1Y) Calculated over the trailing 1-year period	2.72%	0.54%	+2.18%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.59%	0.54%	+3.05%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	3.59%	0.54%	+3.05%

FMUB vs. ZMUN - Expense Ratio Comparison

Both FMUB and ZMUN have an expense ratio of 0.30%.

Dividends

FMUB vs. ZMUN - Dividend Comparison

FMUB's dividend yield for the trailing twelve months is around 3.52%, more than ZMUN's 2.92% yield.

Position	TTM	2025
FMUB Fidelity Municipal Bond Opportunities ETF	3.52%	2.63%
ZMUN F/m Ultrashort Tax-Free Municipal ETF	2.92%	0.70%

Frequently Asked Questions

Can I hold both FMUB and ZMUN in my portfolio?

FMUB and ZMUN have a correlation of 0.26, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which ETF is better, FMUB or ZMUN?

Both ETFs have the same 0.30% expense ratio. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF is cheaper, FMUB or ZMUN?

FMUB and ZMUN have the same expense ratio: 0.30% per year.

Which ETF pays a higher dividend yield, FMUB or ZMUN?

FMUB has the higher dividend yield at 3.52%, compared with 2.92% for ZMUN.

What is the main difference between FMUB and ZMUN?

They also come from different issuers: Fidelity and F/m.