MMMA vs MUB

MMMABNYLI MacKay Muni Allocation ETF

MUBAiShares National Muni Bond ETF

In short

MMMA A December 2025 debut from MacKay's muni team: mostly long-dated investment-grade munis with room for up to 40% high yield. Active credit picking in a corner of the market most funds index. 0.35% net of a fee waiver.

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.

Stated mandate

MMMA The Fund seeks current income that is exempt from regular U.S. federal income tax.

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.

Why people hold it

• MMMA Built long on purpose. Predominantly long-duration investment-grade munis, the slice of the curve where tax-exempt yields are richest, chosen by MacKay's muni desk.nylim.com
• Credit flexibility is written into the mandate: at least 60% investment-grade munis, with up to 40% available for opportunistic non-investment-grade bonds.nylim.comstreetinsider.com
• 0.35% net of a fee waiver (0.72% gross) lands near the muni category median, even though a human team is underwriting every bond.
• Roughly 50 positions, so the team's credit calls actually move the portfolio instead of washing out across thousands of CUSIPs.

• 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

Worth knowing

• MMMA Index rivals cost far less: VTEB and SCMB charge 0.03%, MUB 0.05%. Active muni research is the thing you are paying the difference for.
• Long duration swings both ways. When rates move, prices here move more than a short or intermediate muni fund's.nylim.com
• Launched December 2025, still small and thinly traded. New-fund disclosures note there is no assurance it reaches an economically viable size.nylim.com

• 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.

Full MMMA profile⁠

Full MUB profile⁠