MMHYX Performance — MFS Municipal High Income Fund, Class A

Data updated: 2026-09-28

MMHYX returned +1.89% year to date and +7.87% over one year to Jul 2026. Annualised returns are +5.25% over 3 years and +0.57% over 5 years. The fund beat its Long-Term Municipal Bond category average: $100 invested three years ago grew to $117, against $110 for the category, and to $108 over one year, against $106. Volatility over the past three years was 6.76% a year. In the 12 months to Jul 2026 the fund took in a net $573.5M, and assets reached $5.57B.

MMHYX Growth of $100

What $100 invested in MFS Municipal High Income Fund grew to, compounded from monthly returns reported on SEC Form N-PORT, against the Long-Term Municipal Bond category average over the same months.

PeriodMMHYXCategory average
1 year (Aug 2025 – Jul 2026)$108$106
3 years (Aug 2023 – Jul 2026)$117$110
5 years (Aug 2021 – Jul 2026)$103$101
Since data start (Aug 2019 – Jul 2026)$115$110

MMHYX Trailing Returns

Total returns to Jul 2026, from SEC N-PORT.

PeriodTotal return
YTD+1.89%
1 year+7.87%
3 years (annualised)+5.25%
5 years (annualised)+0.57%

MMHYX Annual Returns

Calendar-year total returns of MFS Municipal High Income Fund, compounded from monthly SEC N-PORT returns. Partial years show the months covered.

YearTotal return
2026 (Jan–Jul)+1.89%
2025+3.52%
2024+7.10%
2023+6.15%
2022−13.84%
2021+5.31%
2020+3.38%
2019 (Aug–Dec)+2.34%

MMHYX Monthly Returns

Monthly total returns as reported on SEC Form N-PORT.

YearJanFebMarAprMayJunJulAugSepOctNovDec
2026+0.8%+1.6%−2.0%+1.3%+0.9%+1.2%−1.8%—————
2025+0.5%+1.4%−1.9%−1.3%−0.6%+0.6%−1.0%+0.7%+3.3%+1.5%+0.4%0.0%
2024+0.5%+0.5%+0.8%−1.3%+0.6%+3.1%+1.2%+1.1%+1.7%−1.3%+1.5%−1.5%
2023+3.7%−2.8%+1.5%+0.4%−0.6%+0.5%+0.2%−1.3%−3.4%−2.1%+7.1%+3.2%
2022−2.8%−0.9%−3.6%−3.1%+1.0%−3.2%+3.2%−2.6%−5.7%−1.8%+5.6%−0.5%
2021+1.8%−1.0%+0.5%+1.3%+1.0%+1.1%+1.1%−0.4%−0.9%−0.4%+1.2%+0.2%
2020+1.9%+1.8%−8.8%−3.3%+2.9%+3.2%+2.3%−0.1%+0.2%−0.2%+2.4%+1.6%
2019———————+2.1%−0.4%−0.1%+0.3%+0.4%

MMHYX Risk

Risk measures from monthly returns over Aug 2023 – Jul 2026.

  • 3-year volatility (annualised): 6.76%
  • 3-year Sharpe ratio: 0.11 (vs 4.5% risk-free rate)
  • Best month: +7.15% (Nov 2023)
  • Worst month: −3.43% (Sep 2023)

MMHYX Fund Flows

Monthly money in and out of MFS Municipal High Income Fund, from SEC Form N-PORT.

  • 12-month net flow: $573.5M
  • 12-month gross sales (incl. reinvestments): $1.9B
  • Sales ÷ redemptions: 1.42×
MonthSalesRedemptionsNet flow
Jul 2026$116.0M$99.5M$16.5M
Jun 2026$115.1M$91.6M$23.4M
May 2026$258.7M$86.7M$172.0M
Apr 2026$120.2M$101.9M$18.3M
Mar 2026$108.8M$104.9M$3.9M
Feb 2026$154.5M$79.9M$74.6M
Jan 2026$138.9M$98.7M$40.1M
Dec 2025$174.7M$151.0M$23.8M
Nov 2025$241.5M$101.1M$140.4M
Oct 2025$175.8M$143.5M$32.2M
Sep 2025$152.9M$132.0M$20.9M
Aug 2025$169.9M$162.4M$7.5M

MMHYX Assets Under Management

Net assets of MFS Municipal High Income Fund by report date, from SEC N-PORT filings.

Report dateNet assets
2026-07-31$5.57B
2026-04-30$5.40B
2026-01-31$5.32B
2025-10-31$5.11B
2025-07-31$4.84B
2025-04-30$4.82B
2025-01-31$4.73B
2024-10-31$4.54B
2024-07-31$4.39B
2024-04-30$4.16B
2024-01-31$4.29B
2023-10-31$3.92B

For information only. Not investment advice: figures are as reported in SEC filings and may contain errors or be out of date. Past performance does not guarantee future results.