iShares National Muni Bond ETF
U.S. bond index ETF · tracks ICE AMT-Free US National Municipal Index
As of its 2026 Q2 report, iShares National Muni Bond ETF held 6,654 positions with $44.95B in net assets. Its ten largest holdings made up 2.6% of the fund. The MUB share class costs 0.05% a year. Over the 12 months to May 2026, MUB returned 6.3%, with dividends reinvested. In 2026 Q2 it added 508 new positions and exited 118.
The iShares National Muni Bond ETF (the Fund ) seeks to track the investment results of an index composed of investment-grade U.S. municipal bonds.
The fund tracks the ICE AMT-Free US National Municipal Index using representative sampling, holding a sample of investment-grade municipal bonds issued by U.S. states and municipalities rather than all index constituents. Because the fund does not hold all components of the index, its returns may diverge from the index it seeks to track. The fund invests at least 80% of assets in index securities and may use futures, options, and swaps to optimize tracking.
What you own
| Company | Weight | Value | Shares |
|---|---|---|---|
MCSXXBlackRock Liquidity Funds | 1.28% | $574.31M | — |
Board of Regents of the University of Texas System 5.00% · due 2036-08-15 | 0.19% | $86.65M | — |
New York State Thruway Authority 5.00% · due 2048-03-15 | 0.15% | $68.62M | — |
San Antonio Water System | 0.14% | $63.98M | — |
Triborough Bridge & Tunnel Authority | 0.14% | $60.97M | — |
New York City Transitional Finance Authority Future Tax Secured | 0.13% | $59.40M | — |
New York State Dormitory Authority 4.00% · due 2047-02-15 | 0.13% | $59.35M | — |
Ohio State University (The) 5.00% · due 2035-06-01 | 0.13% | $57.75M | — |
Houston Higher Education Finance Corp. 5.00% · due 2034-05-15 | 0.13% | $57.66M | — |
Northwest Independent School District 5.25% · due 2055-02-15 | 0.13% | $57.41M | — |
The 200 largest of 6,654 holdings, with the share counts as filed, open with a free account.
What the fund is made of
Percentages are of fund net assets. Rounding, liabilities and short positions can make totals differ from 100%.
| Bonds | 95.56% |
| Cash & short-term | 3.97% |
How it has done
MUB share class · total returns with dividends reinvested
Volatility over the last 12 months: 3.65%. Past returns are a record, not a forecast.
Fees & fund details
iShares National Muni Bond ETF is a U.S. bond index ETF that tracks the ICE AMT-Free US National Municipal Index.
- Asset class
- Bonds
- Region
- United States
- Management
- Index (passive)
- Fund type
- ETF
- Credit quality
- Investment grade
- Rate sensitivity
- Intermediate duration
- Expense ratio, by class
- 0.05%· MUB 0.05%
- Portfolio turnover
- 11.00% a year · as of 2026 Q2
Turnover is how much of the portfolio was replaced in a year.
Classified from what the fund holds, not from its name · 2026 Q2. The summary is a paraphrase of the prospectus; the objective is verbatim.
What changed this quarter
Positions that entered or left the fund since its previous filing. Positions that were only resized are not listed.
508 new· the largest 7
118 exited· the largest 7
Debt profile
What this fund holds — value-weighted across its bond and securitized long positions · as of 2026-05-31
Share of the fund's debt by how its coupon behaves — the fact that decides whether a rate move reaches this portfolio at all.
| Fixed rate | 96.7% |
| Zero-coupon or unclassified | 1.9% |
| Floating rate | 1.4% |
Share of the fund's debt value in each maturity band, shortest first.
| <1y | 3.2% |
| 1-3y | 7.1% |
| 3-5y | 8.5% |
| 5-10y | 21.6% |
| 10y+ | 59.5% |
Based on what filers reported; a filer that never reported a flag also reads as none.
Risk profile
Interest-rate and credit-spread sensitivity, both in years · as of 2026Q2
More of this fund’s sensitivity sits in credit spreads than in interest rates — a rate rally that comes with a credit selloff works against it.
Where the loss would come from. The two shocks are the same size, so this is the balance of the fund's two sensitivities rather than a bet on one moving more.
| Credit spreads | 50% |
| Interest rates | 50% |
Filers report the impact of a 0.01% move only, so the total is our own scaling of that one number and overstates the loss on most bonds — read it as approximate, never as precise. The two sensitivities overlap rather than add up: they measure the same positions against different shocks, which is why the durations above are shown side by side and never summed.
Share of the fund's spread duration carried by each credit tier.
| Investment grade | +6.34 yr |
| High yield | +0.01 yr |
Share of duration at each point, shortest first. A positive figure loses value when spreads widen; a negative one offsets — a credit hedge.
| 3 mo | 0.03 yr | 0% |
| 1 yr | 0.28 yr | 4% |
| 5 yr | 2.23 yr | 36% |
| 10 yr | 2.28 yr | 36% |
| 30 yr | 1.45 yr | 23% |
| 3 mo | 0.03 yr | 0% |
| 1 yr | 0.31 yr | 5% |
| 5 yr | 3.20 yr | 50% |
| 10 yr | 1.80 yr | 28% |
| 30 yr | 1.01 yr | 16% |
The two bands measure the same positions against different shocks and do not add — a Treasury carries rate duration and no spread duration, a floating-rate credit the reverse. Rate tenors are also summed across every currency the fund discloses.
Show the numbers
| Tenor | Rate yrs | IG yrs | HY yrs | IG $/bp | HY $/bp |
|---|---|---|---|---|---|
| 3 mo | +0.03 | +0.03 | +0.00 | $129.9k | $1.1k |
| 1 yr | +0.28 | +0.31 | +0.00 | $1.40m | $3.5k |
| 5 yr | +2.23 | +3.19 | +0.00 | $14.35m | $21.1k |
| 10 yr | +2.28 | +1.80 | +0.00 | $8.10m | $0 |
| 30 yr | +1.45 | +1.01 | +0.00 | $4.54m | $0 |
Dollar change per 1bp of spread movement, as filed and sign-anchored. A blank cell was not filed; a zero was.
Understand how this fund fits with the rest.
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