mub stock: iShares National Muni Bond ETF

iShares National Muni Bond ETF (MUB)

Keyword note: This page covers mub stock (the ticker MUB), an exchange-traded fund that tracks a broad index of investment-grade U.S. municipal bonds. MUB is not a cryptocurrency.

Introduction

The term mub stock commonly refers to the iShares National Muni Bond ETF (ticker: MUB). In this guide you will learn what mub stock is, why investors use it, how the fund is structured, its tax characteristics, costs, liquidity features, risks, and where to verify current metrics. Reading this article will help you decide whether mub stock fits a tax-aware fixed income sleeve in your portfolio and how to locate authoritative data from the issuer and market data providers.

As of 2026-01-28, according to the iShares product page and public fund documents, mub stock (MUB) is one of the largest broad-market U.S. municipal bond ETFs and distributes income monthly. Readers should verify live figures such as AUM, SEC yield, and expense ratio on the issuer site and major market quote pages before making decisions.

Overview

mub stock is an exchange-traded fund managed by iShares (BlackRock) that seeks to track a national, investment-grade, AMT-free municipal bond index. The fund invests primarily in state and local government bonds that historically provide interest exempt from federal income tax for many U.S. taxpayers. Typical investor use cases for mub stock include seeking tax-exempt income, reducing taxable-equivalent yield requirements for high-bracket investors, and adding broad municipal exposure for diversification against taxable bond holdings.

Investors commonly consider mub stock for: income generation in taxable accounts, a tax-efficient alternative to taxable bond funds, and a liquid instrument for municipal bond exposure without buying individual municipal issues.

Fund Details

Ticker, Exchange and Identifiers

• Ticker: MUB
• Exchange: NYSE Arca (traded intraday like other U.S. ETFs)
• Identifiers: CUSIP, ISIN, and Bloomberg identifiers are published in the fund’s prospectus and on the issuer product page. For the most current identifier values, consult the iShares product documentation or the fund’s SEC filings.

Launch and Sponsor

mub stock (MUB) was launched by iShares, a BlackRock company, as a broad national municipal bond ETF. As of the issuer documentation, the fund’s inception date and sponsor details are provided in the prospectus and fact sheet. Investors should consult the official iShares documents for the exact launch date and sponsor disclosures.

Benchmark Index

MUB seeks to track a market-weighted index of U.S. investment-grade municipal bonds that are generally exempt from federal income tax. The fund’s benchmark is a national AMT-free municipal index maintained by a recognized index provider (see issuer documentation for the precise index name used by the fund). The index aims to represent the broad, investment-grade portion of the U.S. municipal market and typically applies rules for minimum issue size, minimum remaining term, and credit-quality thresholds.

Investment Objective and Strategy

mub stock has the stated objective of tracking the performance, before fees and expenses, of a broad, investment-grade U.S. municipal bond index. The fund invests in a diversified portfolio of municipal bonds issued by states, cities, counties, and governmental agencies. Key strategy elements include:

• Market-weighted replication or representative sampling to track the benchmark index.
• Focus on investment-grade credit quality to limit exposure to high-yield municipal credits.
• Broad diversification across issuers, sectors (general obligation vs. revenue bonds), and maturities.
• Target duration and maturity profile designed to match the underlying index; those metrics change over time with market conditions.

The fund uses either full replication (buying substantially all index constituents) or sampling (buying a cross-section that closely matches index characteristics) depending on market liquidity and transaction costs. Creation and redemption by authorized participants help keep market price aligned with NAV.

Holdings and Portfolio Composition

mub stock holds a large, diversified basket of municipal bonds. Typical portfolio characteristics include:

• Security types: General obligation bonds, revenue bonds, project-backed municipal debt, and other state/local government obligations.
• Number of holdings: The fund often holds thousands of individual municipal bonds to achieve broad market representation; exact holding counts fluctuate and are published daily by the issuer.
• Sector/geographic concentration: Because MUB tracks a national index, geographic exposure is spread across states and municipalities. Exposure to large states and issuers will be proportionate to their outstanding issuance in the index.
• Credit quality distribution: The fund emphasizes investment-grade municipal credits (rated BBB/Baa and above by major credit rating agencies), with a portion of holdings in higher-rated (AA/AAA) and some in lower-investment-grade, consistent with the index rules.

For the most recent full holdings list, weighting by state, maturity buckets, and credit rating breakdown, consult the MUB holdings page and the fund’s monthly fact sheet on the issuer site.

Performance and Returns

Historical performance for mub stock is reported in total return terms (including income and price changes) for several standard periods: year-to-date, 1-year, 3-year, 5-year, 10-year, and since inception. When comparing performance users should consider:

• NAV-return versus market-price return: ETFs report performance based on NAV and also reflect market trading prices; small differences can occur when spreads or intraday premiums/discounts are present.
• Interest rate environment: Municipal bond prices are sensitive to changes in interest rates; returns reflect the combined effect of coupon income and price movements due to yield shifts.
• Past performance is not a guarantee of future results.

As of 2026-01-28, performance metrics and trailing returns for mub stock are available on iShares product pages and major financial data providers. Investors should always use up-to-date performance data from the issuer or regulated market-data providers when evaluating the fund.

Distributions and Tax Treatment

mub stock pays income distributions monthly, reflecting interest earned on the underlying municipal bonds. Key tax characteristics:

• Federal income tax: Most interest distributed by MUB has historically been exempt from U.S. federal income tax for many investors, because the underlying municipal bonds generate federally tax-exempt interest. The fund’s distribution statements and tax documents specify the portion of distributions exempt from federal tax.
• Alternative Minimum Tax (AMT): Some municipal bonds can be subject to the AMT; the fund’s distributions can include income subject to AMT. The issuer reports AMT-related amounts when applicable.
• State and local tax: Exemption from state and local taxes depends on the issuing municipality and the investor’s state of residence. National funds like MUB typically do not provide blanket state tax exemption; investors who require state-exempt income often consider state-specific municipal bond funds.
• Tax reporting: At year-end, iShares provides Form 1099-DIV and supplemental tax information detailing the tax status of distributions. Investors should consult their tax advisors for personal tax treatment.

As of 2026-01-28, the fund continues monthly distributions; the most recent SEC 30-day yield and distribution rate are published on the issuer site and major financial portals.

Fees and Expenses

mub stock charges an expense ratio that covers management fees and operating expenses. Historically, MUB’s expense ratio has been competitive among broad municipal bond ETFs. Investors should consider:

• Expense ratio: Check the fund prospectus and iShares product page for the current net expense ratio and any fee waivers.
• Trading costs: In addition to the expense ratio, investors face brokerage commissions (if applicable), bid-ask spread costs, and potential market-impact costs when trading ETF shares.
• Comparison with peers: Expense ratios across municipal bond ETFs vary; some issuer-managed ETFs may offer slightly lower fees or different fee waivers. Compare expense ratio together with tracking error and liquidity when choosing an ETF.

As of 2026-01-28, the current expense ratio and any fee changes are listed on the fund’s official documents. Confirm the latest figure on the iShares product page.

Trading and Liquidity

mub stock trades on NYSE Arca and benefits from the ETF structure’s creation/redemption mechanism that supports market liquidity. Trading and liquidity considerations include:

• Average daily volume: MUB historically shows meaningful average daily traded volume given its size and popularity among municipal bond ETFs. Check real-time volume on market quote pages for up-to-date figures.
• Bid-ask spreads: Spreads for large, widely held ETFs like MUB are typically narrow, but spreads can widen during periods of market stress.
• NAV vs. market price: The ETF’s intraday market price can trade at a small premium or discount to NAV; authorized participants help arbitrage away persistent differences.
• Creation/redemption: Authorized participants create or redeem ETF shares in large blocks (creation units) which helps align supply with demand and keeps market price close to NAV.

For investors who already use Bitget for crypto and token trading, consider that traditional equity and ETF trading occurs on regulated securities exchanges like NYSE Arca. Bitget remains recommended here for crypto and Web3 services, while market-data and trading for mub stock are available through brokerage platforms. For secure custody of crypto assets or integration between tokenized assets and wallets, Bitget Wallet is the suggested Web3 option.

Risks

mub stock carries several principal risks. Understanding these helps investors position the ETF appropriately within a portfolio.

• Interest rate risk: Municipal bond prices fall when interest rates rise; longer-duration municipal exposures are more sensitive to rate changes.
• Credit risk: Though MUB focuses on investment-grade issues, municipal issuers can face credit deterioration that affects bond prices and income stability.
• Liquidity risk: Some underlying municipal securities may be thinly traded; in stressed markets this can increase trading costs and affect the ETF’s market price relative to NAV.
• Tax law and regulatory risk: Changes to federal tax law or municipal finance regulations can alter the tax treatment or attractiveness of municipals, including those held by MUB.
• Concentration risk: While broadly diversified, the fund’s weighting reflects outstanding issuance; states or large issuers with significant issuance may have larger weights.
• Market price vs. NAV risk: Short-term intraday deviations between market price and NAV can occur, particularly during volatile markets.

This is not an exhaustive list. Review the prospectus for detailed risk disclosures and consult trusted sources for updates.

Use in Portfolios

mub stock is commonly used by investors seeking tax-efficient income in taxable accounts. Typical roles include:

• Core municipal allocation for taxable investors who prioritize after-tax yield.
• Diversifier alongside taxable bond funds to reduce overall portfolio tax burden.
• Cash-flowing sleeve for conservative investors seeking regular income with historically lower default rates than comparable corporate high-yield sectors.
• Trading vehicle for tactical duration exposure to the municipal market.

When evaluating mub stock, compare the fund’s after-tax yield (tax-equivalent yield) to taxable alternatives and consider state tax rules for your residency. Always avoid treating this guide as individualized tax or investment advice; consult a tax professional for personal implications.

Comparisons and Alternatives

Investors comparing mub stock to other municipal bond ETFs should evaluate expense ratio, average duration, credit quality distribution, taxable-equivalent yield, and fund size. Examples of comparison points:

• Expense ratio: Compare MUB’s expense ratio with other national municipal ETFs and index funds.
• Duration: Some muni ETFs target short, intermediate, or long durations; match duration to interest-rate views and investment horizon.
• Credit spectrum: Some alternatives focus on high-yield munis or municipal high-coupon issues; MUB targets investment-grade exposure.
• State-specific funds: For state tax exemption, consider state-specific municipal bond funds tailored to your residency.

When performing comparisons, use the issuer pages, fund prospectuses, and independent data providers for accurate and comparable metrics.

Historical Timeline and Notable Events

A concise historical timeline for mub stock includes the fund’s launch, notable AUM milestones, and product updates. Key types of events to monitor include:

• Fund inception and subsequent asset growth milestones.
• Changes in benchmark methodology or index provider announcements affecting tracked index composition.
• Material changes to expense ratio, ticker structure, or share-class offerings.
• Large distribution events or changes in distribution policy.

As of 2026-01-28, consult the iShares product news and SEC filings for an authoritative timeline and any recent corporate actions affecting MUB.

Fund Management and Governance

mub stock is managed by iShares, a division of BlackRock. Management and governance features include:

• Portfolio management: A dedicated municipal bond portfolio team responsible for implementation, sampling/replication decisions, and risk oversight.
• Oversight: BlackRock’s governance framework, compliance, and risk teams provide oversight consistent with regulatory and fiduciary standards.
• Board and trustee information: The fund’s board and governance details are disclosed in the prospectus and annual reports.

For manager biographies, investment process details, and governance documents, refer to the official fund literature.

Data, Reporting and Transparency

iShares provides daily NAVs, daily holdings snapshots, monthly fact sheets, prospectus documents, and shareholder reports for mub stock. Typical transparency elements:

• Daily updated NAV and market-price quotes on market data pages.
• Daily or monthly full holdings disclosure showing security-level positions, weights, maturities, and credit ratings.
• Prospectus and statement of additional information (SAI) with full legal disclosures available from the issuer.
• Distribution and tax reporting (Form 1099-DIV and supplemental materials) provided annually.

As of 2026-01-28, these data points are published on the iShares product page and through major third-party financial information platforms.

References

As of 2026-01-28, the following primary sources provide issuer and market data for mub stock:

• iShares (BlackRock) product page and prospectus for MUB — issuer data, holdings, facts, fee schedule, and tax information.
• Yahoo Finance (MUB) — market quotes, historical prices, and volume figures as reported by market data providers.
• Morningstar — fund analysis, performance, and rating commentary.
• CNBC and other financial news outlets — periodic reporting on muni markets and interest-rate effects.
• Dividend.com and Schwab fund pages — distribution history and yield metrics.

Note: For precise values (AUM, SEC yield, NAV, expense ratio, holdings count), consult the issuer page and SEC filings dated on or before 2026-01-28.

External links

(Do not include clickable links here in this hosted article. Refer to these resources by name and find them through the provider’s official site or regulated market data platforms.)

• iShares product page for MUB (official issuer documentation and prospectus)
• SEC EDGAR filings for the MUB prospectus and annual reports
• Major financial data pages: Yahoo Finance (MUB), Morningstar, and Schwab fund pages for quotes and third-party metrics

See also

• Municipal bonds
• Bond ETFs
• ETF creation and redemption mechanism
• Short- and intermediate-term muni ETFs
• Tax-equivalent yield calculation

Notes on scope and accuracy

This article focuses on mub stock as a municipal bond ETF (not a cryptocurrency) and is intended as an informational reference. Numerical details such as assets under management (AUM), average daily trading volume, SEC yield, and expense ratios change over time. Always verify current figures on the issuer product page and regulated market-data sources. For personal tax implications and suitability, consult a licensed tax professional or financial advisor.

Further exploration and action

If you want to monitor mub stock regularly, check the iShares product page for daily holdings and NAV updates, review monthly fact sheets for distribution and tax details, and follow reputable market-data providers for performance history. For crypto and Web3 custody or trading needs, consider Bitget and Bitget Wallet for secure, user-friendly crypto services; for ETF trading and quotes, use a regulated brokerage that provides access to NYSE Arca.

To explore more ETF fundamentals or broad municipal bond strategies, continue reading our related guides or consult official fund documents to confirm up-to-date metrics before making any investment decisions.

As of 2026-01-28, according to iShares product documentation and public fund disclosures, mub stock (MUB) remains a primary broad-market municipal bond ETF. Investors should use issuer and regulatory filings dated on or before 2026-01-28 for exact numerical values and historical records.