MUB vs NUMI

MUBAiShares National Muni Bond ETF

NUMIBNuveen Municipal Income

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.

NUMI Nuveen underwrote its first municipal bond in 1898. NUMI packs that credit desk into an ETF: roughly 300 mostly investment-grade munis, tilted long, hunting undervalued yield, and paying tax-exempt income monthly for 0.30%.

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.

NUMI The Fund invests at least 80% of its net assets in municipal securities whose interest is exempt from federal income taxes.

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

• NUMI Active, not an index sweep: roughly 300 bonds, primarily investment grade with room for higher-yielding and undervalued names, at a weighted average maturity above 10 years.nuveen.com
• At least 80% of net assets sit in municipal bonds whose interest is exempt from federal income tax, and distributions go out monthly.
• Gross and net fees match at 0.30%, so there is no fee waiver due to roll off and lift the cost later. That lands near the muni category's typical fee.

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.

• NUMI Index rivals charge a fraction: VTEB and SCMB at 0.03%, MUB at 0.05%. The 0.30% here pays for a credit desk picking bonds rather than broad market coverage.
• Long bonds move hard when rates move. The fund concentrates in long maturities and durations, and its own materials flag interest rate, duration and call risk.nuveen.com
• Launched January 2025, it is still a smaller, thinly traded fund, so the spread at the point of trade is worth a look.

Full MUB profile⁠

Full NUMI profile⁠