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MUB vs. SPY
Performance
Return for Risk
Drawdowns
Volatility
Dividends

MUB vs. SPY

Last updated Jun 5, 2026

MUB (iShares National AMT-Free Muni Bond ETF) and SPY (State Street SPDR S&P 500 ETF) are both exchange-traded funds - MUB is a Municipal Bonds fund tracking the S&P National AMT-Free Municipal Bond Index, while SPY is a S&P 500 fund tracking the S&P 500 Index. Both are passively managed. Over the past 10 years, MUB returned 2.01%/yr vs 15.48%/yr for SPY. At a correlation of -0.04, they often move in opposite directions. MUB charges 0.07%/yr vs 0.09%/yr for SPY.

Performance

MUB vs. SPY - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares National AMT-Free Muni Bond ETF (MUB) and State Street SPDR S&P 500 ETF (SPY). The values are adjusted to include any dividend payments, if applicable.

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Returns By Period

In the year-to-date period, MUB achieves a 1.41% return, which is significantly lower than SPY's 11.33% return. Over the past 10 years, MUB has underperformed SPY with an annualized return of 2.01%, while SPY has yielded a comparatively higher 15.48% annualized return.

MUB

1D
0.17%
1M
0.66%
YTD
1.41%
6M
1.92%
1Y
6.87%
3Y*
3.41%
5Y*
0.89%
10Y*
2.01%

SPY

1D
0.38%
1M
4.60%
YTD
11.33%
6M
11.25%
1Y
28.50%
3Y*
22.58%
5Y*
13.91%
10Y*
15.48%
*Multi-year figures are annualized to reflect compound growth (CAGR)

MUB vs. SPY - Yearly Performance Comparison

2026 (YTD)202520242023202220212020201920182017
MUB
iShares National AMT-Free Muni Bond ETF		1.41%3.78%1.26%5.56%-7.34%1.02%5.12%7.06%0.93%4.72%
SPY
State Street SPDR S&P 500 ETF		11.33%17.72%24.89%26.18%-18.18%28.73%18.33%31.22%-4.57%21.71%

Correlation

The correlation between MUB and SPY is 0.27, which is low. Their price movements are largely independent, making them effective diversification partners.

Correlation
Correlation (1Y)
Calculated over the trailing 1-year period

0.27

Correlation (3Y)
Calculated over the trailing 3-year period

0.23

Correlation (5Y)
Calculated over the trailing 5-year period

0.19

Correlation (10Y)
Calculated over the trailing 10-year period

0.06

Correlation (All Time)
Calculated using the full available price history since Sep 11, 2007

-0.04

The correlation between MUB and SPY shifts across timeframes, from -0.04 (all time) to 0.27 (1 year), reflecting how their relationship changes across market environments.

Compare stocks, funds, or ETFs

Search for stocks, ETFs, and funds for a quick comparison or use the comparison tool for more options.

iShares National AMT-Free Muni Bond ETF

State Street SPDR S&P 500 ETF

Often compared with MUB:
MUB vs. VTEBMUB vs. SUBMUB vs. CMFMUB vs. NYFMUB vs. MUNIMUB vs. HYDMUB vs. VWIUX
Often compared with SPY:
SPY vs. QQQSPY vs. VOOSPY vs. BRK-BSPY vs. RSPSPY vs. VTISPY vs. SCHDSPY vs. GLD

Return for Risk

MUB vs. SPY — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.
MUB
MUB Risk / Return Rank: 6868
Overall Rank
MUB Sharpe Ratio Rank: 7474
Sharpe Ratio Rank
MUB Sortino Ratio Rank: 7878
Sortino Ratio Rank
MUB Omega Ratio Rank: 8383
Omega Ratio Rank
MUB Calmar Ratio Rank: 5151
Calmar Ratio Rank
MUB Martin Ratio Rank: 5252
Martin Ratio Rank
SPY
SPY Risk / Return Rank: 7474
Overall Rank
SPY Sharpe Ratio Rank: 7676
Sharpe Ratio Rank
SPY Sortino Ratio Rank: 7474
Sortino Ratio Rank
SPY Omega Ratio Rank: 7575
Omega Ratio Rank
SPY Calmar Ratio Rank: 6666
Calmar Ratio Rank
SPY Martin Ratio Rank: 7878
Martin Ratio Rank
The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

MUB vs. SPY - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares National AMT-Free Muni Bond ETF (MUB) and State Street SPDR S&P 500 ETF (SPY). 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.

MUBSPYDifference
Sharpe ratioReturn per unit of total volatility
2.37
2.42

-0.05

Sortino ratioReturn per unit of downside risk
3.46
3.29

+0.17

Omega ratioGain probability vs. loss probability

1.50

1.44

+0.06

Calmar ratioReturn relative to maximum drawdown

2.48

3.22

-0.75

Martin ratioReturn relative to average drawdown

8.74

14.99

-6.25

Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MUB vs. SPY - Sharpe Ratio Comparison

The current MUB Sharpe Ratio is 2.37, which is comparable to the SPY Sharpe Ratio of 2.42. The chart below compares the historical Sharpe Ratios of MUB and SPY, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

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Sharpe Ratios by Period

MUBSPYDifference

Sharpe Ratio (1Y)

Calculated over the trailing 1-year period

2.37

2.42

-0.05

Sharpe Ratio (5Y)

Calculated over the trailing 5-year period

0.22

0.82

-0.60

Sharpe Ratio (10Y)

Calculated over the trailing 10-year period

0.41

0.87

-0.46

Sharpe Ratio (All Time)

Calculated using the full available price history

0.59

0.59

0.00

Drawdowns

MUB vs. SPY - Drawdown Comparison

The maximum MUB drawdown since its inception was -13.68%, smaller than the maximum SPY drawdown of -55.19%. Use the drawdown chart below to compare losses from any high point for MUB and SPY.

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Drawdown Indicators

MUBSPYDifference

Max Drawdown

Largest peak-to-trough decline

-13.68%

-55.19%

+41.51%

Max Drawdown (1Y)

Largest decline over 1 year

-2.79%

-8.88%

+6.09%

Max Drawdown (3Y)

Largest decline over 3 years

-5.34%

-18.76%

+13.42%

Max Drawdown (5Y)

Largest decline over 5 years

-11.88%

-24.50%

+12.62%

Max Drawdown (10Y)

Largest decline over 10 years

-13.68%

-33.72%

+20.04%

Current Drawdown

Current decline from peak

-0.53%

-0.33%

-0.20%

Average Drawdown

Average peak-to-trough decline

-2.23%

-9.05%

+6.82%

Ulcer Index

Depth and duration of drawdowns from previous peaks

0.79%

1.91%

-1.12%

Volatility

MUB vs. SPY - Volatility Comparison

The current volatility for iShares National AMT-Free Muni Bond ETF (MUB) is 0.98%, while State Street SPDR S&P 500 ETF (SPY) has a volatility of 2.79%. This indicates that MUB experiences smaller price fluctuations and is considered to be less risky than SPY based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

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Volatility by Period

MUBSPYDifference

Volatility (1M)

Calculated over the trailing 1-month period

0.98%

2.79%

-1.81%

Volatility (6M)

Calculated over the trailing 6-month period

2.22%

8.91%

-6.69%

Volatility (1Y)

Calculated over the trailing 1-year period

2.92%

11.82%

-8.90%

Volatility (5Y)

Calculated over the trailing 5-year period, annualized

4.06%

17.05%

-12.99%

Volatility (10Y)

Calculated over the trailing 10-year period, annualized

4.92%

17.93%

-13.01%

MUB vs. SPY - Expense Ratio Comparison

MUB has a 0.07% expense ratio, which is lower than SPY's 0.09% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

MUB vs. SPY - Dividend Comparison

MUB's dividend yield for the trailing twelve months is around 3.17%, more than SPY's 0.98% yield.

PositionTTM20252024202320222021202020192018201720162015
MUB
iShares National AMT-Free Muni Bond ETF		3.17%3.14%3.01%2.65%2.11%1.81%2.11%2.42%2.46%2.26%2.21%2.51%
SPY
State Street SPDR S&P 500 ETF		0.98%1.07%1.21%1.40%1.65%1.20%1.52%1.75%2.04%1.80%2.03%2.06%

Frequently Asked Questions

MUB and SPY have a correlation of 0.27, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

SPY has higher volatility (2.79%) compared to MUB (0.98%). In terms of maximum drawdown, MUB dropped -13.68% vs SPY's -55.19%.

On 10-year performance, SPY leads with 15.48% vs 2.01% for MUB. On fees, MUB is cheaper at 0.07% per year. On volatility, MUB has been the lower-risk option at 0.98%. The better choice depends on whether you care most about return, fees, risk, or income.

Over the 10-year period, SPY has performed better with a 15.48% return vs 2.01%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

MUB is cheaper with a 0.07% expense ratio, compared with 0.09% for SPY.

MUB has the higher dividend yield at 3.17%, compared with 0.98% for SPY.

MUB is categorized as Municipal Bonds, while SPY is S&P 500. MUB tracks S&P National AMT-Free Municipal Bond Index, while SPY tracks S&P 500 Index. They also come from different issuers: iShares and State Street. Their fees differ too: 0.07% for MUB and 0.09% for SPY.

SPY currently has the higher Sharpe Ratio (2.42 vs 2.37), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.

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