At a glance
MUB charges 0.05% a year, below the 0.24% average of the 7 funds most like it (the 2nd cheapest of 8). It has $45.38B in assets, the 2nd largest of that group; it paid 3.3% of its price in distributions over the past 12 months, monthly. Over the past year it returned −0.2% with distributions reinvested, 4th of those 8 funds; over three years it returned +3.7% a year. At its worst it fell 13.7% in the 2020 crash (S&P 500: 33.7%) and 10.6% in the 2022 bear market (S&P 500: 24.5%), and was back at its earlier high 4 months and 24 months after the lows. Its ten largest positions make up 1.3% of the fund, out of 7,002 in all.
The short version
iShares National Muni Bond ETF (MUB) is a BlackRock index fund tracking the ICE AMT-Free US National Municipal Index: investment-grade bonds from US states and local governments, with interest exempt from federal income tax and the alternative minimum tax. It charges 0.05% a year, versus a 0.24% average for similar muni funds; Vanguard's VTEB charges 0.03%. Income arrives monthly, with a 3.3% yield from the past year's payouts as of October 27, 2026.
Price history
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MUB -0.2% over the year to Nov 2, 2026, total return with distributions reinvested.
How it has behaved
| YTD | 1 yr | 3 yr | 5 yr | 10 yr | Since start | |
|---|---|---|---|---|---|---|
| MUB official prospectus, to Dec 31, 2025 | — | +3.69% | — | +0.77% | +2.13% | — |
| MUB price data to Nov 2, 2026 | -0.6% | -0.2% | +3.7% | +0.6% | +1.8% | +3.0% |
- Over the year to Nov 2, 2026, MUB returned -0.2%, 4th of 8 among similar funds.
- Its 5-year annualized return was +0.6% and its 10-year +1.8%.
- In the 2020 COVID crash it fell 13.7% and regained its old high 4.4 months after the low.
- Its worst full calendar year was 2022 (-7.3%); its best was 2011 (+13.0%).
- The deepest fall in its price history was 13.7% (Mar 9, 2020 to Mar 19, 2020), recovered by Jul 30, 2020.
Show as a table
| Year | Price data | Prospectus (official) |
|---|---|---|
| 2026 (to date) | -0.6% | — |
| 2025 | +3.8% | +3.69% |
| 2024 | +1.3% | +1.11% |
| 2023 | +5.5% | +5.86% |
| 2022 | -7.3% | -7.50% |
| 2021 | +1.0% | +1.24% |
| 2020 | +5.1% | +4.87% |
| 2019 | +7.0% | +7.28% |
| 2018 | +0.9% | +0.86% |
| 2017 | +4.7% | +4.61% |
| 2016 | -0.2% | +0.06% |
| 2015 | +2.9% | — |
| 2014 | +9.3% | — |
| 2013 | -3.5% | — |
| 2012 | +5.2% | — |
| 2011 | +13.0% | — |
| 2010 | +0.1% | — |
| 2009 | +7.1% | — |
| 2008 | +1.2% | — |
| 2008 financial crisis stocks fell Oct 9, 2007 – Mar 9, 2009 | Gained 3.6% over that stretch · deepest drop along the way 12.3%, back to its old high 2.8 months after the low |
|---|---|
| 2020 COVID crash stocks fell Feb 19, 2020 – Mar 23, 2020 | Lost 9.9% over that stretch · deepest drop along the way 13.7%, back to its old high 4.4 months after the low |
| 2022 bear market stocks fell Jan 3, 2022 – Oct 12, 2022 | Lost 9.5% over that stretch · deepest drop along the way 10.6%, back to its old high 23.7 months after the low |
Dividends and income
Show as a table
| Year | Per share | Change |
|---|---|---|
| 2026 (to date) | $2.5700 | |
| 2025 | $3.3800 | +5.3% |
| 2024 | $3.2100 | +12.6% |
| 2023 | $2.8500 | +27.8% |
| 2022 | $2.2300 | +6.2% |
| 2021 | $2.1000 | -15.3% |
| 2020 | $2.4800 | -9.8% |
| 2019 | $2.7500 | +2.6% |
| 2018 | $2.6800 | +7.2% |
| 2017 | $2.5000 | +5.0% |
| 2016 | $2.3800 | -14.1% |
| 2015 | $2.7700 | -7.7% |
| 2014 | $3.0000 | -3.8% |
| 2013 | $3.1200 | -2.8% |
| 2012 | $3.2100 | -10.6% |
| 2011 | $3.5900 | -5.0% |
| 2010 | $3.7800 | +1.9% |
| 2009 | $3.7100 | +5.1% |
| 2008 | $3.5300 |
Living on MUB: its income record, cuts, and how much a $1,000 monthly income takes →
What's inside
As of Aug 31, 2026, the fund held 7,002 securities; the ten largest made up 1.31% of assets, and 2.1% sat in cash and money-market holdings.
| Holding | Weight | |
|---|---|---|
| Board of Regents of the University of Texas System Bonds and notes | 0.18% | |
| New York State Thruway Authority Bonds and notes | 0.15% | |
| New York State Dormitory Authority Bonds and notes | 0.13% | |
| Northwest Independent School District Bonds and notes | 0.12% | |
| Houston Higher Education Finance Corp. Bonds and notes | 0.12% | |
| State of New Jersey Bonds and notes | 0.12% | |
| Ohio State University (The) Bonds and notes | 0.12% | |
| State of Washington Bonds and notes | 0.12% | |
| State of California Bonds and notes | 0.12% | |
| Chicago Transit Authority Sales Tax Receipts Fund Bonds and notes | 0.11% | |
| East County Advanced Water Purification Joint Powers Authority Bonds and notes | 0.11% | |
| New Jersey Educational Facilities Authority Bonds and notes | 0.11% | |
| State of Illinois Bonds and notes | 0.11% | |
| Washoe County School District Bonds and notes | 0.11% | |
| Commonwealth of Massachusetts Bonds and notes | 0.10% |
By country
United States 97.44%By issuer
Municipalities 97.44%The bonds mature in 13.5 years on average (weighted by size), with an average coupon of 4.68%.
Source: N-PORT holdings report as of Aug 31, 2026. Cash, money-market funds and derivatives are shown separately from the securities list.What changed recently
- Over the three months to Aug 31, 2026, investors added a net $1.31B (creations minus redemptions, per the N-PORT report).
- Monthly total returns reported for that quarter: +0.75%, -1.68%, -0.17%.
How it works
MUB tracks the ICE AMT-Free US National Municipal Index, built by ICE Data Indices. The index covers tax-exempt bonds issued by US states and local governments; it had 26,009 issues as of February 28, 2026. Each bond must be investment grade (the higher credit-rating tiers): at least BBB- from S&P or Fitch, or Baa3 from Moody's, and the lowest rating counts. It also needs an original offering of at least $100 million, at least $15 million still outstanding and at least a month left to maturity.
Bonds are weighted by market value, so bigger issues count for more, with a cap to limit concentration. The index rebalances on the last calendar day of each month. The fund doesn't necessarily hold every bond; BlackRock uses representative sampling, picking a subset that matches the index on duration (sensitivity to interest rates), maturity, credit quality and yield. At least 80% of assets must be index bonds, and up to 10% may go into futures, options, swaps or other bonds that aid tracking.
The fund generally holds bonds whose interest is exempt from federal income tax and the alternative minimum tax (AMT), a parallel tax that can hit some higher earners. Cash goes into affiliated municipal money market funds. It doesn't try to beat the index or shift to cash when markets fall.
What it really costs
- MUB charges 0.05% a year, versus an average of 0.24% for the similar funds below (2nd of 8, cheapest first).
- Using the prospectus's standard example, $10,000 invested would cost about $5 in the first year and $64 over 10 years (assuming a 5% annual return).
| Cost of $10,000 (SEC example) | 1 yr | 3 yrs | 5 yrs | 10 yrs |
|---|---|---|---|---|
| MUB | $5 | $16 | $28 | $64 |
Structure and tax notes
- Bond prices move opposite to interest rates; the longer the maturities it holds, the more its price reacts to rate changes.
In a retirement portfolio
It pays monthly interest that is largely exempt from federal income tax, which matters most for retirees holding bonds in taxable accounts.
MUB pays interest monthly; its trailing 12-month yield was 3.3% as of October 27, 2026. That interest is largely free of federal income tax, so it tends to add more in a taxable account than an IRA. Costs are low at 0.05% a year: the SEC's standard $10,000 example shows $64 in expenses over 10 years.
It is calmer than stocks but not crash-proof. Across the 2007–09 stock slide it gained 3.6%, though it briefly fell 12.3% in fall 2008. Its deepest drop, 13.7% in March 2020, took 4.4 months to recover. It slid 10.6% from peak to low in 2022, its worst calendar year (down 7.5%), and took 23.7 months to recover. Anyone drawing income through a stretch like that may have to cash out shares at depressed prices. Past results don't predict the future, and a plan should look at the whole portfolio, not one fund.
Who it may suit — and who should look elsewhere
May suit
- Investors in higher tax brackets seeking monthly income free from federal income tax and the alternative minimum tax, held in a taxable brokerage account.
- Cost-conscious investors: the 0.05% fee works out to $5 in the first year on $10,000 under the SEC's standard example, versus a 0.24% peer average.
- Investors wanting broad national muni exposure: 7,002 holdings as of August 31, 2026; the largest, a University of Texas bond, was 0.18% of assets.
Look elsewhere if
- Savers investing through IRAs or other tax-deferred accounts, where the federal tax exemption brings no extra benefit and taxable bonds typically yield more.
- Those needing steady prices: an average maturity of 13.5 years makes it rate-sensitive, and it lost 7.5% in 2022, recovering fully only by September 2024.
- Those needing growth or inflation protection: average annual returns were 0.77% over five years and 2.13% over 10 years through December 31, 2025.
Close alternatives
Matched by bond funds with the closest average maturity and issuer mix (N-PORT).
| Fund | Avg. maturity | Cost | Net assets | 1 yr | 3 yr |
|---|---|---|---|---|---|
| MUB this fund | 13.5 yrs | 0.05% | $45.38B | -0.2% | +3.7% |
| VTEB Vanguard Tax-Exempt Bond ETF | 14.5 yrs | 0.03% | $48.52B | +0.1% | +4.4% |
| CMF iShares California Muni Bond ETF | 12.4 yrs | 0.08% | $4.63B | -0.6% | +3.8% |
| ITM VanEck Intermediate Muni ETF | 12.4 yrs | 0.18% | $2.12B | -0.3% | +4.6% |
| TFI SPDR Nuveen Bloomberg Municipal Bond ETF | 15.1 yrs | 0.23% | $3.12B | -0.8% | +3.9% |
| FMB First Trust Managed Municipal ETF | 15.5 yrs | 0.65% | $2.05B | 0.0% | +4.3% |
| MUNI PIMCO Intermediate Municipal Bond Active Ex… | 15.3 yrs | 0.35% | $3.09B | +0.2% | +4.7% |
| JMUB JPMorgan Municipal ETF | 16.7 yrs | 0.18% | $8.75B | -0.2% | +4.4% |
Questions investors ask
Is MUB tax-free?
Mostly at the federal level. MUB generally holds municipal bonds whose interest is exempt from federal income tax and the alternative minimum tax. As of its June 2026 prospectus, that interest is also exempt from the 3.8% Medicare tax on net investment income. State income tax may still apply. This national fund holds bonds from many states, including Texas, New York and California, and many states tax interest from out-of-state bonds. Capital gains, including any profit when shares are cashed out, are taxable.
Does MUB pay monthly dividends?
Yes. MUB pays income every month. Over the 12 months through October 27, 2026, it paid $3.43 per share, a 3.3% yield on its share price. Most of that income comes from municipal bond interest, so it is largely exempt from federal income tax. Payments can shift: the prospectus warns that income may fall when bonds mature or are called (repaid early by the issuer) and the fund must reinvest at lower rates.
What's the difference between MUB and VTEB?
The differences are small. Both are large national muni bond ETFs. Vanguard's VTEB has a 0.03% expense ratio, versus 0.05% for MUB. VTEB had $48.5 billion in net assets as of July 31, 2026; MUB had $45.4 billion as of August 31, 2026. VTEB's bonds averaged 14.5 years to maturity, against 13.5 for MUB, which may make VTEB slightly more sensitive to interest-rate moves. Returns through October 27, 2026 were nearly identical: -0.4% versus -0.3% over one year, and 4.2% versus 4.0% a year over three years.
Can you lose money in MUB?
Yes. Bond prices fall when interest rates rise. MUB's bonds averaged 13.5 years to maturity as of August 31, 2026, so rate moves matter. Its prospectus shows a 7.5% loss in 2022 and a 5.6% drop in the first quarter of that year. Its deepest decline was 13.7%, in March 2020, and it took 4.4 months to recover. Credit risk also applies. The index requires investment-grade ratings, but an issuer could still struggle to pay, and ratings can lag an issuer's real finances.
What are MUB's top holdings?
No single bond dominates. As of August 31, 2026, MUB held 7,002 holdings, and the 10 largest made up just 1.31% of assets. The biggest were a University of Texas System Series 2025B bond (0.18%), a New York State Thruway Authority bond (0.15%) and a New York State Dormitory Authority bond (0.13%). The top 10 also included bonds from New Jersey, Washington, California, Ohio State University and the Chicago Transit Authority. Bonds were 97.4% of assets and cash 2.1%.