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Fidelity Merrimack Street Trust
2026-07-31
Fidelity® Municipal Bond Opportunities ETF
Fidelity® Municipal Bond Opportunities ETF
FMUB
NASDAQ
This semi-annual shareholder report contains information about Fidelity® Municipal Bond Opportunities ETF for the period February 1, 2026 to July 31, 2026.
semi-annual shareholder report
You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-FIDELITY or by sending an e-mail to fidfunddocuments@fidelity.com.
fundresearch.fidelity.com/prospectus/sec
1-800-FIDELITY
fidfunddocuments@fidelity.com
<span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;">What were your Fund costs for the last six months?</span>
<div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">(based on hypothetical $10,000 investment)</span></div>
<div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"> </span></div>
<span style="line-height:12px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
<div style="text-align:left;text-align-last:auto;"><table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"><tr><td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"><div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"> </span></div>
</td>
<td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"><div style="text-align:center;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">Costs of a $10,000 investment</span></div>
</td>
<td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"><div style="text-align:center;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">Costs paid as a percentage of a $10,000 investment </span></div>
</td>
<td style="width:1%; " valign="top"><span style="line-height:12px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
</tr>
<tr><td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"><div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Municipal Bond Opportunities ETF</span><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"> </span></div>
</td>
<td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:center;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">$</span><span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"> </span>15<span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"> </span></div>
</td>
<td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:center;text-align-last:auto;">0.30<span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">%</span></div>
</td>
<td style="width:1%; " valign="top"><span style="line-height:12px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
</tr>
</table>
</div>
<div style="text-align:left;text-align-last:auto;"></div>
15
0.0030
<span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;">Key Fund Statistics</span>
<div style="text-align:left;text-align-last:auto;"></div>
<div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">(as of July 31, 2026)</span></div>
<div><span style="font-size:11px;"> </span></div><div style="text-align:left;text-align-last:auto;"></div>
<div style="text-align:right;text-align-last:auto;"><table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"><tr><td style="width:63%; " valign="top"><div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;">KEY FACTS</span><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"> </span></div>
</td>
<td style="width:32%; " valign="top"><span style="line-height:12px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
<td style="width:5%; " valign="top"><span style="line-height:12px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
</tr>
<tr><td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Fund Size</span></div>
</td>
<td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:right;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">$</span>243,673,728</div>
<div style="text-align:right;text-align-last:auto;"></div>
</td>
<td style="width:5%; " valign="top"><span style="line-height:11px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
</tr>
<tr><td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Number of Holdings</span></div>
</td>
<td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:right;text-align-last:auto;">596</div>
<div style="text-align:right;text-align-last:auto;"></div>
</td>
<td style="width:5%; " valign="top"><span style="line-height:11px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
</tr>
<tr><td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:left;text-align-last:auto;"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Portfolio Turnover</span></div>
</td>
<td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"><div style="text-align:right;text-align-last:auto;">16<span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">%</span></div>
<div style="text-align:left;text-align-last:auto;"></div>
</td>
<td style="width:5%; " valign="top"><span style="line-height:11px;"> </span><div style="text-align:left;text-align-last:auto;"></div>
</td>
</tr>
</table>
</div>
<div style="text-align:left;text-align-last:auto;"></div>
243673728
596
0.16
REVENUE SOURCES
(% of Fund's net assets)
General Obligations
27.6
Health Care
19.7
Transportation
13.6
Housing
10.8
Education
9.0
Special Tax
5.9
Others(Individually Less Than 5%)
10.3
96.9
AAA
5.5
AA
37.7
A
28.9
BBB
11.7
BB
2.1
Not Rated
11.0
Short-Term Investments and Net Other Assets (Liabilities)
3.1
QUALITY DIVERSIFICATION (% of Fund's net assets)
AAA - 5.5
AA - 37.7
A - 28.9
BBB - 11.7
BB - 2.1
Not Rated - 11.0
Short-Term Investments and Net Other Assets (Liabilities) - 3.1
We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.
TOP STATES
(% of Fund's net assets)
Texas
11.4
Alabama
10.6
Illinois
7.3
Florida
5.0
Pennsylvania
4.0
0.276
0.197
0.136
0.108
0.090
0.059
0.103
0.055
0.377
0.289
0.117
0.021
0.110
0.031
0.114
0.106
0.073
0.050
0.040