MRSKX Performance — MFS Research International Fund, Class R6
Data updated: 2026-07-27
MRSKX returned +8.81% year to date and +17.35% over one year to May 2026. Annualised returns are +13.91% over 3 years and +5.76% over 5 years. The fund trailed its International Mid-Cap Blend category average: $100 invested three years ago grew to $148, against $163 for the category, and to $117 over one year, against $122. Volatility over the past three years was 12.50% a year. In the 12 months to May 2026 the fund lost a net $1.2B, and assets reached $17.76B.
MRSKX Growth of $100
What $100 invested in MFS Research International Fund grew to, compounded from monthly returns reported on SEC Form N-PORT, against the International Mid-Cap Blend category average over the same months.
| Period | MRSKX | Category average |
|---|---|---|
| 1 year (Jun 2025 – May 2026) | $117 | $122 |
| 3 years (Jun 2023 – May 2026) | $148 | $163 |
| 5 years (Jun 2021 – May 2026) | $132 | $142 |
| Since data start (Sep 2019 – May 2026) | $185 | $194 |
MRSKX Trailing Returns
Total returns to May 2026, from SEC N-PORT.
| Period | Total return |
|---|---|
| YTD | +8.81% |
| 1 year | +17.35% |
| 3 years (annualised) | +13.91% |
| 5 years (annualised) | +5.76% |
MRSKX Annual Returns
Calendar-year total returns of MFS Research International Fund, compounded from monthly SEC N-PORT returns. Partial years show the months covered.
| Year | Total return |
|---|---|
| 2026 (Jan–May) | +8.81% |
| 2025 | +22.80% |
| 2024 | +3.20% |
| 2023 | +13.49% |
| 2022 | −17.25% |
| 2021 | +12.00% |
| 2020 | +13.29% |
| 2019 (Sep–Dec) | +12.42% |
MRSKX Monthly Returns
Monthly total returns as reported on SEC Form N-PORT.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | +5.7% | +5.0% | −8.9% | +5.4% | +2.1% | — | — | — | — | — | — | — |
| 2025 | +3.9% | +2.0% | −1.0% | +3.2% | +5.1% | +2.2% | −2.8% | +2.3% | +2.1% | +0.8% | +1.0% | +2.2% |
| 2024 | −0.8% | +2.2% | +3.4% | −3.0% | +5.0% | −1.5% | +3.2% | +3.4% | +0.4% | −4.7% | −0.5% | −3.3% |
| 2023 | +7.8% | −3.5% | +2.9% | +3.1% | −4.1% | +3.9% | +2.0% | −2.8% | −4.7% | −3.0% | +7.5% | +4.8% |
| 2022 | −5.4% | −3.3% | −1.0% | −6.3% | +1.8% | −8.0% | +5.4% | −5.6% | −9.7% | +4.4% | +13.0% | −1.8% |
| 2021 | −1.6% | +1.5% | +2.3% | +2.9% | +4.2% | −1.7% | +1.2% | +2.9% | −3.9% | +3.7% | −3.7% | +3.9% |
| 2020 | −1.9% | −6.7% | −12.2% | +6.3% | +5.5% | +3.9% | +3.8% | +4.9% | −1.1% | −4.1% | +11.6% | +5.0% |
| 2019 | — | — | — | — | — | — | — | — | +2.6% | +3.6% | +2.0% | +3.7% |
MRSKX Risk
Risk measures from monthly returns over Jun 2023 – May 2026.
- 3-year volatility (annualised): 12.50%
- 3-year Sharpe ratio: 0.75 (vs 4.5% risk-free rate)
- Best month: +7.49% (Nov 2023)
- Worst month: −8.94% (Mar 2026)
MRSKX Fund Flows
Monthly money in and out of MFS Research International Fund, from SEC Form N-PORT.
- 12-month net flow: −$1.2B
- 12-month gross sales (incl. reinvestments): $1.6B
- Sales ÷ redemptions: 0.57×
| Month | Sales | Redemptions | Net flow |
|---|---|---|---|
| May 2026 | $49.0M | $396.4M | −$347.4M |
| Apr 2026 | $48.1M | $205.8M | −$157.7M |
| Mar 2026 | $69.8M | $247.8M | −$177.9M |
| Feb 2026 | $53.7M | $468.4M | −$414.7M |
| Jan 2026 | $45.5M | $372.7M | −$327.2M |
| Dec 2025 | $947.4M | $394.2M | $553.2M |
| Nov 2025 | $37.0M | $195.4M | −$158.4M |
| Oct 2025 | $64.9M | $152.6M | −$87.6M |
| Sep 2025 | $55.3M | $110.3M | −$55.0M |
| Aug 2025 | $109.2M | $80.3M | $29.0M |
| Jul 2025 | $87.4M | $124.1M | −$36.7M |
| Jun 2025 | $61.6M | $110.9M | −$49.4M |
MRSKX Assets Under Management
Net assets of MFS Research International Fund by report date, from SEC N-PORT filings.
| Report date | Net assets |
|---|---|
| 2026-05-31 | $17.76B |
| 2026-02-28 | $18.84B |
| 2025-11-30 | $17.69B |
| 2025-08-31 | $17.32B |
| 2025-05-31 | $17.10B |
| 2025-02-28 | $16.31B |
| 2024-11-30 | $16.09B |
| 2024-08-31 | $17.01B |
| 2024-05-31 | $16.62B |
| 2024-02-29 | $16.26B |
| 2023-11-30 | $15.67B |
| 2023-08-31 | $16.06B |
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.