Fund Evaluator:
MFS MA Municipal Bond B (MBMAX)
Follow This Fund
Best Performing in Muni Massachusetts Over the Last Year
| 6.5% | Vanguard MA Tax-Exempt Inv (VMATX) |
| 4.9% | Fidelity Massachusetts Municipal Income (FDMMX) |
| 3.7% | Columbia Massachusetts Itmt MuncplBdInst (SEMAX) |
| 3.5% | BNY Mellon MA Interm Muni Bd M (MMBMX) |
Fund Details
MFS MA Municipal Bond B Overview
MFS MA Municipal Bond B (MBMAX) is an actively managed Municipal Bond Muni Massachusetts fund. MFS launched the fund in 1993.
The investment seeks total return with an emphasis on income exempt from U.S. federal income tax and personal income tax, if any, of Massachusetts, but also considering capital appreciation. The fund invests, under normal market conditions, at least 80% of its net assets in securities and other investments, the interest on which is exempt from U.S. federal income tax and personal income tax, if any, of Massachusetts. It may also invest the fund's assets in taxable instruments, including municipal instruments of other states.
About MFS MA Municipal Bond B (MBMAX)
There are 2 members of the management team with an average tenure of 13.97 years: Thomas Compton (2026), Michael Dawson (1999). Management tenure is more important for actively managed funds than passive index funds.
The fund has 1 primary benchmark: Bloomberg Municipal TR USD index with a weighting of 100%. MFS MA Municipal Bond B has 267 securities in its portfolio. The top 10 holdings constitute 11.5% of the fund’s assets. The fund meets the SEC requirement of being classified as a diversified fund. The fund is not considered to have an ESG focus with its investment selection and management.
MFS MA Municipal Bond B is part of the Fixed Income global asset class and is within the Municipal Bond fund group. MFS MA Municipal Bond B has 3.4% of its portfolio invested in foreign issues. The overall assets allocated to domestic stock is 0.0%. There is 0.0% allocated to foreign stock, and 0.0% is allocated to preferred stocks. The bond allocation as a percentage of total assets is 97.9% (94.5% domestic bond, 3.4% foreign bond and 0.0% convertible bond). MFS MA Municipal Bond B has 2.1% of the portfolio in cash.
Assets Under Management
The fund has $42 million in total assets, which is below the $217 million average for the Muni Massachusetts category. Normally, lower assets under management translates to higher average expense ratios, and greater total assets are desired. However, for some investment categories, such as small-cap investing, it may be difficult for the manager to fully employ the desired active strategy if assets grow too large or too quickly.
MBMAX Performance and Fees
The expense ratio measures how much of a fund’s assets are used for administrative expenses and operating expenses, including adviser fees and fees for the transfer agent and custodial services. The MFS MA Municipal Bond B expense ratio is high compared to funds in the Muni Massachusetts category. MFS MA Municipal Bond B has an expense ratio of 1.57%, which is 92% higher than its category average, making the fund expense ratio grade a F. While it is difficult to predict returns, it is known that high annual expense ratios reduce your rate of return, and excessive fees are difficult to overcome. Active management normally comes with higher expense ratios than passive index management. Certain investment categories such as small company and foreign also normally have higher expense ratios. It is best to compare fund expense ratios against the category averages for meaningful assessments.
High portfolio turnover can translate to higher expenses and lower aftertax returns. MFS MA Municipal Bond B has a portfolio turnover rate of 12%, indicating that holds its assets around 0.1 years. By way of comparison, the average portfolio turnover is 25% for the Muni Massachusetts category.
Recently, in the month of July 2026, MFS MA Municipal Bond B returned -1.9%, which earned it a grade of F, as the Muni Massachusetts category had an average return of -1.8%. The letter grades of A, B, C, D and F are based upon relative rankings within the investment category. A grade of A, for example, would indicate that the return is in the highest 20% for that time period compared to all funds in that category.
MFS MA Municipal Bond B has a trailing yield of 2.54%, which is below the 2.95% category average. The fund normally distributes its income monthly and its capital gains annually.
It’s natural to seek the best-performing investments, but you must consider the relationship between risk and return and the impact of costs and taxes on your realized returns.
MFS MA Municipal Bond B Grades
Year to date, the fund has returned 0.4%, 0.0 percentage points worse than the category, which translates into a grade of D. The fund has returned 5.5% over the past year (grade of C), 2.4% over the past three years (grade of D) and -0.6% per year over the past five years (grade of F) and 0.8% per year over the past 10 years (grade of F).
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MBMAX Trailing NAV Total Returns Data as of 7/31/26
| Last Month |
Last Quarter |
Ann'l. 1Yr |
Ann'l. 3Yr |
Ann'l. 5Yr |
Ann'l. 10Yr |
|
| MBMAX Return (NAV) | -1.9% | -0.5% | 5.5% | 2.4% | -0.6% | 0.8% |
| MBMAX Grade | F | D | C | D | F | F |
| +/- Category | -0.1% | -0.0% | 0.3% | -0.2% | -0.4% | -0.4% |
| Muni Massachusetts Avg | -1.8% | -0.5% | 5.2% | 2.6% | -0.2% | 1.2% |
| MBMAX Tax Cost Ratio | na | na | 0.0% | 0.0% | 0.0% | 0.0% |
MBMAX Annual NAV Total ReturnsData as of 7/31/26
| 2026 | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | |
| MBMAX Return (NAV) | 0.4% | 2.2% | 1.5% | 5.3% | -10.9% | 1.3% | 2.8% | 6.5% | -0.0% | 4.0% | -0.4% |
| MBMAX Grade | D | F | B | D | D | B | F | D | D | D | C |
| +/- Category | -0.0% | -1.0% | 0.3% | -0.1% | -1.0% | 0.1% | -1.4% | -0.3% | -0.2% | -0.5% | -0.2% |
| Muni Massachusetts Avg | 0.4% | 3.2% | 1.2% | 5.5% | -9.9% | 1.2% | 4.2% | 6.8% | 0.2% | 4.5% | -0.2% |
| Risk Measures | |
| Standard Deviation: | 6.1% |
| Total Risk Index: | 0.49 - Below Average |
| Category Risk Index: | 1.11 - High |
| Category Risk Grade: | F (97% Rank) |
| Beta: | 1.04 |
| R-Squared: | 97% |
| Leveraged Fund: | No |
| Inverse Fund: | No |
| Portfolio Characteristics | |
| Equity Investment Style: | na |
| Bond Investment Style: | High Quality Extensive Sensitivity |
| Yield: | 2.5% |
| Dividend Distribution: | Monthly |
| Cap Gains Distribution: | Annually |
| Total Assets: | $412 Mil |
| Fund Total Assets: | $ 0 Mil |
| Share Class Type: | B |
| Portfolio Turnover: | 12% |
Management Team
| Number of Managers: 2 | |||
| Longest Tenure: 27.6 years | |||
| Average Tenure: 14.0 years | |||
| Managers (Year): Dawson Michael (1999), Compton Thomas (2026) | |||
Portfolio Composition (as of 6/30/26)
| # of Holdings: | 267 |
| % in Top 10 Holdings: | 11.5% |
| Fund is Non-Diversified: | No |
| % in Foreign Issues: | 3.4% |
Portfolio Allocation |
|
| Domestic Stock: | 0.0% |
| Foreign Stock: | 0.0% |
| Preferred Stock: | 0.0% |
| Domestic Bond: | 94.5% |
| Foreign Bond: | 3.4% |
| Convertible Bond: | 0.0% |
| Other: | 0.0% |
| Cash: | 2.1% |
Purchase Information
| Fund Family: | MFS |
| Phone Number: | 800-225-2606 |
| Website: | http://www.mfs.com |
| Status: | Closed |
| Inception Date: | September 7, 1993 |
| Min. Initial Purchase: | $1,000 |
| Min. Initial IRA Purchase: | $ 250 |
| True No-Load: | No |
| Front Load Maximum: | 0.00% |
| Deferred Charge Maximum: | 4.00% |
| Redemption Charge Maximum: | 0.00% |
| 12b-1 Fee: | 1.00% |
Expenses and Fees | |
| Expense Ratio (%): | 1.57% ( Rating : High ) |
| Category Average Expense Ratio (%): | 0.82% |
| Share Class: | MFS MA Municipal Bond A |
| Min. Subsequent Purchase: | $ 0 |
| Min. Subsequent IRA Purchase: | $ 0 |
