MFSM vs MUB
MFS Active Intermediate Muni Bond ETF against iShares National Muni Bond ETF: cost, size, returns, what they hold and how much of it is the same.
Overlap by weight
0%
10 shared positions
Fee gap
29 bp
MUB is cheaper
1-year return gap
0.2 pts
MFSM is ahead
Larger fund
MUB
$55.0B
Side by side
| MFSM | MUB | |
|---|---|---|
| Fund | MFS Active Intermediate Muni Bond ETF | iShares National Muni Bond ETF |
| Issuer | MFS | iShares |
| Category | National Muni | National Muni |
| Expense ratio | 0.34% | 0.05% |
| Assets | $104M | $55.0B |
| Average daily dollar volume | $3.5M | $1.6B |
| Listed | Dec 4, 2024 | Sep 7, 2007 |
| FrenzyCap score | 50 | 99 |
| 1-month return | +4.3% | +4.1% |
| 3-month return | −1.0% | −0.9% |
| Year to date | −1.9% | −2.1% |
| 1-year return | −1.8% | −1.9% |
| 30-day volatility | 6.4% | 5.7% |
| Worst drawdown, 1 year | −8.4% | −7.9% |
| Trailing 12-month yield | 3.59% | 3.26% |
| Holdings | 419 | 7,991 |
| Top 10 weight | 6.8% | 1.2% |
| Look-through P/E | — | — |
| Holdings vs fair value | — | — |
| Holdings above 200-day average | — | — |
| Net flow, latest 3 reported months | +$6.8M thru Aug 2026 | +$1.3B thru Aug 2026 |
| 30-day implied volatility | — | 7.3% |
| Holdings as of | as of Aug 31, 2026SEC filing | as of Nov 6, 2026issuer data |
Returns are price returns and exclude distributions. Flows are each fund's own latest reported months and may not cover the same period.
Largest shared holdings
3% of MFSM · 0% of MUB| Holding | MFSM | MUB |
|---|---|---|
| Grand Parkway Transportation Corp 5%, due Oct 1, 2043 | 0.29% | 0.02% |
| New Jersey Transportation Trust Fund Authority 4.25%, due Jun 15, 2040 | 0.20% | 0.02% |
| State of Illinois 5.5%, due May 1, 2039 | 0.25% | 0.01% |
| Illinois State Toll Highway Authority 5.25%, due Jan 1, 2045 | 0.15% | 0.01% |
| San Antonio Public Facilities Corp 4%, due Sep 15, 2042 | 0.34% | 0.01% |
| Board of Water Commissioners City & County of Denver/The 5%, due Sep 15, 2047 | 0.20% | 0.01% |
| New York City Transitional Finance Authority Future Tax Secured Revenue 5%, due May 1, 2042 | 0.25% | 0.00% |
| Arapahoe County School District No 5 Cherry Creek, due Dec 15, 2042 | 0.52% | 0.00% |
| State of Washington 5%, due Aug 1, 2046 | 0.10% | 0.00% |
| Intermountain Power Agency 5%, due Jul 1, 2038 | 0.27% | 0.00% |
Sector mix of the stock holdings
No sector breakdown: these funds hold few classified stocks.
More: full overlap table · MFSM holdings · MUB holdings
Fund data comes from each fund's SEC filings and issuer disclosures and is shown with the date it is as of. SEC portfolio and flow filings become public about 60 days after the period they cover. Nothing here is investment advice; see Terms.