0001140869
tsr:C000133025Member
2025-09-01
2026-08-31
0001140869
tsr:C000133025Member
2026-08-31
0001140869
tsr:bench202410244121_8410Member
tsr:C000133025Member
2026-08-31
0001140869
tsr:bench202410244123_8410Member
tsr:C000133025Member
2026-08-31
0001140869
tsr:bench202410244124_8410Member
tsr:C000133025Member
2026-08-31
0001140869
2025-09-01
2026-08-31
iso4217:USD
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iso4217:USD
shares
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0001140869
N-1A
N-CSR
Master Portfolio Trust
2026-08-31
U.S. Treasury Obligations Portfolio
U.S. Treasury Obligations Portfolio
2026-08-31
<span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">This </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">annual shareholder report</span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;"> contains important information about </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">U.S. Treasury Obligations Portfolio for the period </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">September 1, 2025, </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">to </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">August 31, 2026.</span>
annual shareholder report
<span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">You can find additional information about the Fund at </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;;">https://www.franklintempleton.com/regulatory-masterfunds-documents</span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">. You can </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">also request this information by contacting us at </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">1-800-625-4554, or 1-203-703-6002</span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#161616;;">.</span>
https://www.franklintempleton.com/regulatory-masterfunds-documents
1-800-625-4554, or 1-203-703-6002
3
<div><span style="text-transform:uppercase;"><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:12.024pt;text-transform:uppercase;color:#1447FF;;"><b>KEY FUND STATISTICS </b></span></span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.824pt;color:#2D2D2D;;">(as of </span><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.824pt;color:#2D2D2D;;">August 31, 2026)</span></div><div>
<table cellspacing="0" style="width:98%;cellspacing:0;border-top:1.5pt solid #6B6B6B;margin-left:7.75pt;border-bottom:1.5pt solid #6B6B6B;margin-top:10px;">
<tr style="height:1px;">
<td style="height:1px;width:74.41007194244604%;"></td>
<td style="height:1px;width:25.58992805755396%;"></td>
</tr>
<tr>
<td colspan="1" style="border-bottom:0.75pt solid #6B6B6B;vertical-align:top">
<div style="background-color:#FFFFFF;padding-left:2pt;padding-top:1pt;padding-bottom:0;align:left;text-align:left;padding-right:2pt;font-family:Arial, Helvetica, sans-serif;font-size:10pt;margin-top:1pt;margin-bottom:0;"><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#2D2D2D;;"><b>Total Net Assets</b></span></div>
</td>
<td colspan="1" style="border-bottom:0.75pt solid #6B6B6B;vertical-align:bottom">
<div style="background-color:#FFFFFF;padding-left:2pt;padding-top:1pt;padding-bottom:0;align:right;text-align:right;padding-right:2pt;font-family:Arial, Helvetica, sans-serif;font-size:10pt;margin-top:1pt;margin-bottom:0;"><span style="font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;">$912,398,729</span></div>
</td>
</tr>
<tr>
<td colspan="1" style="border-bottom:0.75pt solid #6B6B6B;vertical-align:top">
<div style="background-color:#FFFFFF;padding-left:2pt;padding-top:1pt;padding-bottom:0;align:left;text-align:left;padding-right:2pt;font-family:Arial, Helvetica, sans-serif;font-size:10pt;margin-top:1pt;margin-bottom:0;"><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#2D2D2D;;"><b>Total Number of Portfolio Holdings</b></span></div>
</td>
<td colspan="1" style="border-bottom:0.75pt solid #6B6B6B;vertical-align:bottom">
<div style="background-color:#FFFFFF;padding-left:2pt;padding-top:1pt;padding-bottom:0;align:right;text-align:right;padding-right:2pt;font-family:Arial, Helvetica, sans-serif;font-size:10pt;margin-top:1pt;margin-bottom:0;"><span style="font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;">29</span></div>
</td>
</tr>
<tr>
<td colspan="1" style="vertical-align:top">
<div style="background-color:#FFFFFF;padding-left:2pt;padding-top:1pt;padding-bottom:0;align:left;text-align:left;padding-right:2pt;font-family:Arial, Helvetica, sans-serif;font-size:10pt;margin-top:1pt;margin-bottom:0;"><span style="clear:both;font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;color:#2D2D2D;;"><b>Total Management Fee Paid</b></span></div>
</td>
<td colspan="1" style="vertical-align:bottom">
<div style="background-color:#FFFFFF;padding-left:2pt;padding-top:1pt;padding-bottom:0;align:right;text-align:right;padding-right:2pt;font-family:Arial, Helvetica, sans-serif;font-size:10pt;margin-top:1pt;margin-bottom:0;"><span style="font-family:Arial, Helvetica, sans-serif;font-size:10.02pt;">$0</span></div>
</td>
</tr>
</table></div>
912398729
29
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https://www.franklintempleton.com/regulatory-masterfunds-documents
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*Expense amounts may be voluntarily waived and/or reimbursed from time to time.