v3.26.3
Shareholder Report
 6 Months Ended
Aug. 31, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name MFS ACTIVE EXCHANGE TRADED FUNDS TRUST
Entity Central Index Key 0002018846
Entity Investment Company Type N-1A
Document Period End Date Aug. 31, 2026
C000251000 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active Core Plus Bond ETF
Class Name MFS® Active Core Plus Bond ETF
Trading Symbol MFSB
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active Core Plus Bond ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active Core Plus Bond ETF $17 0.34%
Expenses Paid, Amount $ 17
Expense Ratio, Percent 0.34%
Net Assets $ 551,107,936
Holdings Count | Holding 464
Investment Company Portfolio Turnover 24.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 551,107,936 Average Effective Maturity (yrs): 9.1
Total Number of Holdings: 464 Average Effective Duration (yrs): 5.8
Portfolio Turnover Rate (%): 24
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Fixed Income 97.3%
Money Market Funds 2.7%
Composition including fixed income credit quality
AAA 9.7%
AA 4.6%
A 13.4%
BBB 27.6%
BB 6.6%
B 4.0%
CCC 0.7%
U.S. Government 23.9%
Federal Agencies 6.8%
Money Market Funds 2.7%
Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change.
Credit Ratings Selection [Text Block]
Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change.
C000251001 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active Growth ETF
Class Name MFS® Active Growth ETF
Trading Symbol MFSG
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active Growth ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active Growth ETF $26 0.49%
Expenses Paid, Amount $ 26
Expense Ratio, Percent 0.49%
Net Assets $ 379,210,722
Holdings Count | Holding 68
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 379,210,722 Portfolio Turnover Rate (%): 28
Total Number of Holdings: 68
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 99.3%
Money Market Funds 0.7%
Equity sectors
Information Technology 46.7%
Communication Services 16.0%
Industrials 9.1%
Consumer Discretionary 8.1%
Health Care 7.2%
Financials 6.4%
Consumer Staples 1.9%
Energy 1.8%
Materials 1.8%
Real Estate 0.3%
Top ten holdings
NVIDIA Corp. 14.3%
Alphabet, Inc., "A" 11.2%
Apple, Inc. 6.0%
Microsoft Corp. 5.3%
Broadcom, Inc. 3.4%
Visa, Inc., "A" 3.3%
Amazon.com, Inc. 2.9%
Meta Platforms, Inc., "A" 2.3%
Arista Networks, Inc. 2.0%
GE Vernova, Inc. 1.9%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
NVIDIA Corp. 14.3%
Alphabet, Inc., "A" 11.2%
Apple, Inc. 6.0%
Microsoft Corp. 5.3%
Broadcom, Inc. 3.4%
Visa, Inc., "A" 3.3%
Amazon.com, Inc. 2.9%
Meta Platforms, Inc., "A" 2.3%
Arista Networks, Inc. 2.0%
GE Vernova, Inc. 1.9%
C000251002 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active Intermediate Muni Bond ETF
Class Name MFS® Active Intermediate Muni Bond ETF
Trading Symbol MFSM
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active Intermediate Muni Bond ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active Intermediate Muni Bond ETF $17 0.34%
Expenses Paid, Amount $ 17
Expense Ratio, Percent 0.34%
Net Assets $ 103,765,078
Holdings Count | Holding 419
Investment Company Portfolio Turnover 17.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 103,765,078 Average Effective Maturity (yrs): 8.6
Total Number of Holdings: 419 Average Effective Duration (yrs): 6.4
Portfolio Turnover Rate (%): 17
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Fixed Income 98.1%
Money Market Funds 1.9%
Composition including fixed income credit quality
AAA 2.5%
AA 40.2%
A 31.2%
BBB 17.6%
BB 2.8%
B 0.4%
CC 0.2%
Not Rated 3.2%
Money Market Funds 1.9%
Industries
Healthcare Revenue - Hospitals 10.3%
Utilities - Other 10.0%
Airport Revenue 8.7%
Universities - Colleges 7.6%
Multi-Family Housing Revenue 7.3%
Healthcare Revenue - Long Term Care 6.9%
General Obligations - Schools 6.6%
State & Local Agencies 5.2%
General Obligations - General Purpose 3.7%
Student Loan Revenue 3.6%
Other Industries 28.2%
Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change.
For purposes of these classifications, MFS uses its own internal sector/industry classification methodology, which may deviate from classification methodologies used by other industry participants (e.g., the Global Industry Classification Standard).
Credit Ratings Selection [Text Block]
Ratings are assigned using Moody’s, Fitch, and Standard & Poor’s and applying a hierarchy: If all 3 agencies rate a security, the middle rating is assigned; if 2 agencies rate a security, the lower rating is assigned. If none of the 3 agencies rate a security, we use DBRS Morningstar. If none of the 4 agencies rate a security, we use Kroll Bond Rating Agency. Ratings are shown in the S&P and Fitch scale (e.g., AAA). All ratings are subject to change.
C000251003 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active International ETF
Class Name MFS® Active International ETF
Trading Symbol MFSI
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active International ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active International ETF $30 0.59%
Expenses Paid, Amount $ 30
Expense Ratio, Percent 0.59%
Net Assets $ 1,222,297,101
Holdings Count | Holding 94
Investment Company Portfolio Turnover 5.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 1,222,297,101 Portfolio Turnover Rate (%): 5
Total Number of Holdings: 94
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 98.7%
Money Market Funds 1.3%
Top ten holdings
Taiwan Semiconductor Manufacturing Co. Ltd., ADR 7.3%
Samsung Electronics Co. Ltd. 3.5%
Tencent Holdings Ltd., ADR 2.3%
Schneider Electric SE 2.1%
Hitachi Ltd. 2.0%
Compagnie Financiere Richemont S.A. 2.0%
Rolls-Royce Holdings PLC 2.0%
Novartis AG 1.9%
Roche Holding AG 1.9%
ING Groep N.V. 1.9%
Issuer country weightings
Japan 14.8%
United Kingdom 12.0%
France 11.4%
Switzerland 9.6%
Taiwan 8.4%
China 7.0%
Germany 5.1%
Canada 4.9%
South Korea 3.5%
Other Countries 23.3%
Largest Holdings [Text Block]
Top ten holdings
Taiwan Semiconductor Manufacturing Co. Ltd., ADR 7.3%
Samsung Electronics Co. Ltd. 3.5%
Tencent Holdings Ltd., ADR 2.3%
Schneider Electric SE 2.1%
Hitachi Ltd. 2.0%
Compagnie Financiere Richemont S.A. 2.0%
Rolls-Royce Holdings PLC 2.0%
Novartis AG 1.9%
Roche Holding AG 1.9%
ING Groep N.V. 1.9%
C000251004 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active Value ETF
Class Name MFS® Active Value ETF
Trading Symbol MFSV
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active Value ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active Value ETF $23 0.44%
Expenses Paid, Amount $ 23
Expense Ratio, Percent 0.44%
Net Assets $ 601,124,791
Holdings Count | Holding 62
Investment Company Portfolio Turnover 24.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 601,124,791 Portfolio Turnover Rate (%): 24
Total Number of Holdings: 62
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 99.1%
Money Market Funds 0.9%
Equity sectors
Financials 23.2%
Information Technology 14.7%
Health Care 14.4%
Industrials 14.3%
Consumer Discretionary 9.3%
Utilities 8.4%
Energy 7.0%
Consumer Staples 4.6%
Real Estate 1.6%
Communication Services 0.8%
Materials 0.8%
Top ten holdings
Amazon.com, Inc. 5.4%
Microsoft Corp. 5.4%
JPMorgan Chase & Co. 4.5%
Apple, Inc. 2.9%
ExxonMobil Holdings Corp. 2.8%
Cigna Group 2.6%
RTX Corp. 2.3%
Bank of America Corp. 2.3%
Morgan Stanley 2.2%
Chevron Corp. 2.1%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
Amazon.com, Inc. 5.4%
Microsoft Corp. 5.4%
JPMorgan Chase & Co. 4.5%
Apple, Inc. 2.9%
ExxonMobil Holdings Corp. 2.8%
Cigna Group 2.6%
RTX Corp. 2.3%
Bank of America Corp. 2.3%
Morgan Stanley 2.2%
Chevron Corp. 2.1%
C000263368 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active Mid Cap ETF
Class Name MFS® Active Mid Cap ETF
Trading Symbol MMID
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active Mid Cap ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active Mid Cap ETF $30 0.59%
Expenses Paid, Amount $ 30
Expense Ratio, Percent 0.59%
Net Assets $ 36,220,653
Holdings Count | Holding 107
Investment Company Portfolio Turnover 9.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 36,220,653 Portfolio Turnover Rate (%): 9
Total Number of Holdings: 107
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 96.8%
Money Market Funds 3.2%
Equity sectors
Industrials 17.7%
Financials 15.2%
Information Technology 12.1%
Health Care 11.5%
Consumer Discretionary 9.3%
Real Estate 7.2%
Energy 6.9%
Materials 6.4%
Utilities 5.8%
Consumer Staples 3.5%
Communication Services 1.2%
Top ten holdings
Global Payments, Inc. 1.9%
Cheniere Energy, Inc. 1.7%
Waters Corp. 1.7%
Becton, Dickinson and Co. 1.6%
Diamondback Energy, Inc. 1.6%
Agilent Technologies, Inc. 1.5%
Wabtec Corp. 1.5%
W.W. Grainger, Inc. 1.4%
Valero Energy Corp. 1.4%
STERIS PLC 1.4%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
Global Payments, Inc. 1.9%
Cheniere Energy, Inc. 1.7%
Waters Corp. 1.7%
Becton, Dickinson and Co. 1.6%
Diamondback Energy, Inc. 1.6%
Agilent Technologies, Inc. 1.5%
Wabtec Corp. 1.5%
W.W. Grainger, Inc. 1.4%
Valero Energy Corp. 1.4%
STERIS PLC 1.4%
C000264376 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Blended Research® Core Equity ETF
Class Name MFS® Blended Research® Core Equity ETF
Trading Symbol BRCE
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Blended Research Core Equity ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Blended Research Core Equity ETF $13 0.24%
Expenses Paid, Amount $ 13
Expense Ratio, Percent 0.24%
Net Assets $ 37,024,147
Holdings Count | Holding 105
Investment Company Portfolio Turnover 19.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 37,024,147 Portfolio Turnover Rate (%): 19
Total Number of Holdings: 105
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 99.7%
Money Market Funds 0.3%
Equity sectors
Information Technology 38.4%
Financials 12.8%
Health Care 10.2%
Communication Services 8.7%
Industrials 8.1%
Consumer Discretionary 8.0%
Consumer Staples 5.1%
Energy 3.8%
Utilities 2.1%
Materials 1.4%
Real Estate 1.1%
Top ten holdings
NVIDIA Corp. 9.3%
Apple, Inc. 7.0%
Microsoft Corp. 5.0%
Amazon.com, Inc. 4.1%
Alphabet, Inc., "A" 2.7%
Broadcom, Inc. 2.4%
Johnson & Johnson 2.3%
Salesforce, Inc. 2.2%
Micron Technology, Inc. 2.2%
Mastercard, Inc., "A" 2.1%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
NVIDIA Corp. 9.3%
Apple, Inc. 7.0%
Microsoft Corp. 5.0%
Amazon.com, Inc. 4.1%
Alphabet, Inc., "A" 2.7%
Broadcom, Inc. 2.4%
Johnson & Johnson 2.3%
Salesforce, Inc. 2.2%
Micron Technology, Inc. 2.2%
Mastercard, Inc., "A" 2.1%
C000264377 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Blended Research® International Equity ETF
Class Name MFS® Blended Research® International Equity ETF
Trading Symbol BRIE
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Blended Research International Equity ETF for the period of March 1, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Blended Research International Equity ETF $18 0.34%
Expenses Paid, Amount $ 18
Expense Ratio, Percent 0.34%
Net Assets $ 489,962,608
Holdings Count | Holding 160
Investment Company Portfolio Turnover 18.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 489,962,608 Portfolio Turnover Rate (%): 18
Total Number of Holdings: 160
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 98.0%
Money Market Funds 2.0%
Equity sectors
Financials 24.2%
Information Technology 20.4%
Industrials 13.9%
Consumer Discretionary 6.9%
Health Care 6.8%
Materials 6.3%
Consumer Staples 5.6%
Communication Services 4.8%
Energy 4.8%
Utilities 2.8%
Real Estate 1.5%
Top ten holdings
Taiwan Semiconductor Manufacturing Co. Ltd., ADR 5.1%
ASML Holding N.V. 2.6%
Samsung Electronics Co. Ltd. 2.5%
SK hynix, Inc. 2.1%
Rio Tinto PLC 1.9%
BNP Paribas S.A. 1.7%
Novartis AG 1.7%
ING Groep N.V. 1.7%
Toronto-Dominion Bank 1.6%
UBS Group AG 1.6%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
Taiwan Semiconductor Manufacturing Co. Ltd., ADR 5.1%
ASML Holding N.V. 2.6%
Samsung Electronics Co. Ltd. 2.5%
SK hynix, Inc. 2.1%
Rio Tinto PLC 1.9%
BNP Paribas S.A. 1.7%
Novartis AG 1.7%
ING Groep N.V. 1.7%
Toronto-Dominion Bank 1.6%
UBS Group AG 1.6%
C000267408 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Blended Research® Emerging Markets Equity ETF
Class Name MFS® Blended Research® Emerging Markets Equity ETF
Trading Symbol BREE
Security Exchange Name NYSE
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Blended Research Emerging Markets Equity ETF for the period of March 5, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months#?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Blended Research Emerging Markets Equity ETF $24 0.44%
# For the period from the commencement of the fund’s investment operations, March 5, 2026 through August 31, 2026. Expenses for a full 6 month semiannual period would have been higher.
Expenses Paid, Amount $ 24 [1]
Expense Ratio, Percent 0.44% [1]
Net Assets $ 26,579,681
Holdings Count | Holding 137
Investment Company Portfolio Turnover 14.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 26,579,681 Portfolio Turnover Rate (%): 14
Total Number of Holdings: 137
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 99.0%
Money Market Funds 1.0%
Equity sectors
Information Technology 41.8%
Financials 19.3%
Consumer Discretionary 7.7%
Communication Services 6.8%
Industrials 6.4%
Materials 5.7%
Energy 3.7%
Consumer Staples 3.1%
Health Care 2.7%
Utilities 1.4%
Real Estate 0.4%
Top ten holdings
Taiwan Semiconductor Manufacturing Co. Ltd., ADR 13.6%
SK hynix, Inc. 5.9%
Samsung Electronics Co. Ltd. 5.7%
Tencent Holdings Ltd., ADR 2.9%
Samsung Electronics Co. Ltd. 2.7%
China Construction Bank Corp. 2.2%
Hon Hai Precision Industry Co. Ltd. 1.9%
Alibaba Group Holding Ltd., ADR 1.7%
King Slide Works Co. Ltd. 1.7%
MediaTek, Inc. 1.6%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
Taiwan Semiconductor Manufacturing Co. Ltd., ADR 13.6%
SK hynix, Inc. 5.9%
Samsung Electronics Co. Ltd. 5.7%
Tencent Holdings Ltd., ADR 2.9%
Samsung Electronics Co. Ltd. 2.7%
China Construction Bank Corp. 2.2%
Hon Hai Precision Industry Co. Ltd. 1.9%
Alibaba Group Holding Ltd., ADR 1.7%
King Slide Works Co. Ltd. 1.7%
MediaTek, Inc. 1.6%
C000275596 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Active International Value ETF
Class Name MFS® Active International Value ETF
Trading Symbol MIVL
Security Exchange Name NYSEArca
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Active International Value ETF for the period of June 4, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months#?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Active International Value ETF $14 0.57%
# For the period from the commencement of the fund’s investment operations, June 4, 2026 through August 31, 2026. Expenses for a full 6 month semiannual period would have been higher.
Expenses Paid, Amount $ 14 [2]
Expense Ratio, Percent 0.57% [2]
Net Assets $ 25,072,812
Holdings Count | Holding 63
Investment Company Portfolio Turnover 2.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 25,072,812 Portfolio Turnover Rate (%): 2
Total Number of Holdings: 63
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 99.4%
Money Market Funds 0.6%
Top ten holdings
NatWest Group PLC 4.3%
BNP Paribas S.A. 4.2%
UBS Group AG 3.5%
TotalEnergies SE 3.3%
Eni S.p.A. 2.6%
Glencore PLC 2.5%
British American Tobacco PLC 2.5%
Rio Tinto PLC 2.4%
Barclays PLC 2.4%
Henkel AG & Co. KGaA 2.2%
Issuer country weightings
United Kingdom 29.6%
France 17.9%
Japan 13.6%
Italy 5.5%
Ireland 5.5%
Netherlands 5.2%
Switzerland 5.1%
Germany 5.0%
Canada 4.3%
Other Countries 8.3%
Largest Holdings [Text Block]
Top ten holdings
NatWest Group PLC 4.3%
BNP Paribas S.A. 4.2%
UBS Group AG 3.5%
TotalEnergies SE 3.3%
Eni S.p.A. 2.6%
Glencore PLC 2.5%
British American Tobacco PLC 2.5%
Rio Tinto PLC 2.4%
Barclays PLC 2.4%
Henkel AG & Co. KGaA 2.2%
C000275597 [Member]  
Shareholder Report [Line Items]  
Fund Name MFS® Blended Research® Small-Mid Cap ETF
Class Name MFS® Blended Research® Small-Mid Cap ETF
Trading Symbol BRSM
Security Exchange Name NYSEArca
Annual or Semi-Annual Statement [Text Block] This semiannual shareholder report contains important information about MFS Blended Research Small-Mid Cap ETF for the period of June 4, 2026 to August 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at etfs.mfs.com. You can also request this information by contacting us at 1‑800‑225‑2606 or by sending an e-mail request to orderliterature@mfs.com.
Additional Information Phone Number 1‑800‑225‑2606
Additional Information Email orderliterature@mfs.com
Additional Information Website etfs.mfs.com
Expenses [Text Block]
FUND EXPENSES
What were the fund costs for the last six months#?
(based on a hypothetical $10,000 investment)
Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment (annualized)
MFS Blended Research Small-Mid Cap ETF $9 0.38%
# For the period from the commencement of the fund’s investment operations, June 4, 2026 through August 31, 2026. Expenses for a full 6 month semiannual period would have been higher.
Expenses Paid, Amount $ 9 [3]
Expense Ratio, Percent 0.38% [3]
Net Assets $ 27,525,416
Holdings Count | Holding 312
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block]
FUND STATISTICS AS OF 8/31/26
Net Assets ($): 27,525,416 Portfolio Turnover Rate (%): 13
Total Number of Holdings: 312
Where the fund holds derivatives, they are not included in the total number of portfolio holdings.
Holdings [Text Block]
PORTFOLIO COMPOSITION (BASED ON TOTAL INVESTMENTS AS OF 8/31/26)
Portfolio structure
Equities 99.8%
Money Market Funds 0.2%
Equity sectors
Industrials 17.5%
Financials 17.1%
Information Technology 14.7%
Health Care 13.9%
Consumer Discretionary 10.0%
Real Estate 7.6%
Materials 5.3%
Energy 4.2%
Utilities 3.4%
Communication Services 3.3%
Consumer Staples 2.8%
Top ten holdings
TechnipFMC PLC 1.1%
Roku, Inc. 1.1%
Box, Inc., "A" 1.1%
Aramark 1.0%
Universal Health Services, Inc. 1.0%
Everest Group Ltd. 1.0%
BILL Holdings, Inc. 1.0%
Popular, Inc. 1.0%
Lincoln National Corp. 1.0%
UGI Corp. 0.9%
MFS uses the Global Industry Classification Standard (GICS®) for sector/industry reporting. MFS has applied its own internal sector/industry classification methodology for equity securities and non-equity securities that are unclassified by GICS.
Largest Holdings [Text Block]
Top ten holdings
TechnipFMC PLC 1.1%
Roku, Inc. 1.1%
Box, Inc., "A" 1.1%
Aramark 1.0%
Universal Health Services, Inc. 1.0%
Everest Group Ltd. 1.0%
BILL Holdings, Inc. 1.0%
Popular, Inc. 1.0%
Lincoln National Corp. 1.0%
UGI Corp. 0.9%
[1] For the period from the commencement of the fund’s investment operations, March 5, 2026 through August 31, 2026. Expenses for a full 6 month semiannual period would have been higher.
[2] For the period from the commencement of the fund’s investment operations, June 4, 2026 through August 31, 2026. Expenses for a full 6 month semiannual period would have been higher.
[3] For the period from the commencement of the fund’s investment operations, June 4, 2026 through August 31, 2026. Expenses for a full 6 month semiannual period would have been higher.