MUB vs MUNX

MUBAiShares National Muni Bond ETF

MUNXCAMG GW&K Muni Income ETF

In short

MUB Municipal bonds, indexed and cheap. Since 2007, MUB has packaged investment-grade national munis into tax-exempt monthly income for five basis points a year, and it sits among the deepest pools in the muni-ETF aisle.

MUNX A Boston bond boutique's muni playbook in an ETF wrapper. GW&K's team picks individual tax-exempt bonds across sectors, maturities and credit tiers, aiming at federally tax-free income instead of mirroring an index.

Stated mandate

MUB The fund seeks to track an index of investment-grade U.S. municipal bonds, providing diversified exposure to the national municipal-bond market and tax-exempt income.

MUNX The Fund seeks current income exempt from federal income tax while preserving capital. Capital appreciation is a secondary objective.

Why people hold it

• MUB 0.05% a year against a muni-ETF median near 0.30%. In a category built on modest, tax-exempt yields, that fee gap is real money left in the fund.
• The benchmark is AMT-free: the ICE AMT-Free US National Municipal Index screens out munis whose interest can be pulled into the alternative minimum tax.ishares.com
• Tracks its index closely, one of the tighter jobs in its peer group, and distributes monthly. A multi-billion-dollar fund that trades actively.
• Broad investment-grade exposure across the national muni market, spread over thousands of issuers rather than one state's budget.ishares.com

• MUNX Actively run rather than index-shadowing: managers can shift sectors, maturities and credit quality inside a muni market where many bonds trade by appointment.amgetfs.com
• At 0.29% a year, it charges a shade under the typical muni bond ETF while running an active book instead of a rules-based one.
• Clear job description: core intermediate US munis, federally tax-exempt income first, capital preservation alongside it, price appreciation only a secondary goal.amgetfs.com
• Income is designed to arrive monthly per the fund's filings, and the portfolio stays tightly inside that tax-exempt muni mandate with no side bets.

Worth knowing

• MUB Two rivals undercut it: VTEB and SCMB both run 0.03%. A two-basis-point gap is small, but it is a gap.
• A bond fund with no maturity date to hold to. Share prices move with interest rates and muni credit conditions, both directions.
• National by design, so no single-state tilt and no in-state tax angle. iShares runs state-specific muni funds such as NYF for that job.

• MUNX Index munis undercut it sharply: VTEB and SCMB charge 0.03%. Active bond selection is the entire reason to pay the difference here.
• Launched in late 2025, so the record is short and trading has been light. Spreads can run wider than the big muni index funds, which makes execution matter.
• Payout timing has been uneven early on, and the exemption is federal only: state taxes and bonds subject to the AMT are still in play.aaii.com

Full MUB profile⁠

Full MUNX profile⁠