diff --git a/ly/musicxml/ly2xml_mediator.py b/ly/musicxml/ly2xml_mediator.py
index e67004e..5b18068 100644
--- a/ly/musicxml/ly2xml_mediator.py
+++ b/ly/musicxml/ly2xml_mediator.py
@@ -564,6 +564,7 @@ def new_chordbase(self, note, duration, rel=False):
         self.current_note.set_duration(duration)
         self.current_lynote = note
         self.check_current_note(rel)
+        self.increase_bar_dura(duration)
 
     def new_chordnote(self, note, rel):
         chord_note = self.create_barnote_from_note(note)
@@ -600,6 +601,7 @@ def copy_prev_chord(self, duration):
                 cn.set_tie('stop')
             self.bar.add(cn)
         self.tied = False
+        self.increase_bar_dura(duration)
 
     def clear_chord(self):
         self.q_chord = self.current_chord
diff --git a/tests/test_xml.py b/tests/test_xml.py
index a3eb5df..e5ca26b 100644
--- a/tests/test_xml.py
+++ b/tests/test_xml.py
@@ -76,6 +76,10 @@ def test_no_barcheck():
     compare_output('no_barcheck')
 
 
+def test_chord_duration():
+    compare_output('chord_duration')
+
+
 def ly_to_xml(filename):
     """Read Lilypond file and return XML string."""
     writer = ly.musicxml.writer()
diff --git a/tests/test_xml_files/chord_duration.ly b/tests/test_xml_files/chord_duration.ly
new file mode 100644
index 0000000..df2dea3
--- /dev/null
+++ b/tests/test_xml_files/chord_duration.ly
@@ -0,0 +1,15 @@
+\version "2.24.0"
+
+% Test chord duration counting for bar boundaries (issue #171)
+% Both explicit chords and duration shorthand must count toward measure duration
+
+\score {
+  <<
+    % Explicit chord notation: 3 measures
+    \new Staff { c''1 | <d'' f'' a''>1 | e''1 }
+
+    % Duration shorthand after chord: 3 measures
+    \new Staff { \time 3/4 <e' f'>4 4 4 | 4 4 8 r8 | r4 a' g' }
+  >>
+  \layout { }
+}
diff --git a/tests/test_xml_files/chord_duration.xml b/tests/test_xml_files/chord_duration.xml
new file mode 100644
index 0000000..0992e3e
--- /dev/null
+++ b/tests/test_xml_files/chord_duration.xml
@@ -0,0 +1,254 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!DOCTYPE score-partwise PUBLIC "-//Recordare//DTD MusicXML 2.0 Partwise//EN"
+                                "http://www.musicxml.org/dtds/partwise.dtd">
+<score-partwise version="3.0">
+  <identification>
+    <encoding>
+      <software>python-ly 0.9.9</software>
+      <encoding-date>2026-01-26</encoding-date>
+    </encoding>
+  </identification>
+  <part-list>
+    <score-part id="P1">
+      <part-name />
+    </score-part>
+    <score-part id="P2">
+      <part-name />
+    </score-part>
+  </part-list>
+  <part id="P1">
+    <measure number="1">
+      <attributes>
+        <divisions>2</divisions>
+        <time>
+          <beats>3</beats>
+          <beat-type>4</beat-type>
+        </time>
+        <clef>
+          <sign>G</sign>
+          <line>2</line>
+        </clef>
+      </attributes>
+      <note>
+        <pitch>
+          <step>C</step>
+          <octave>5</octave>
+        </pitch>
+        <duration>8</duration>
+        <voice>1</voice>
+        <type>whole</type>
+      </note>
+      <backup>
+        <duration>8</duration>
+      </backup>
+    </measure>
+    <measure number="2">
+      <note>
+        <pitch>
+          <step>D</step>
+          <octave>5</octave>
+        </pitch>
+        <duration>8</duration>
+        <voice>1</voice>
+        <type>whole</type>
+      </note>
+    </measure>
+    <measure number="3">
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>5</octave>
+        </pitch>
+        <duration>8</duration>
+        <voice>1</voice>
+        <type>whole</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>A</step>
+          <octave>5</octave>
+        </pitch>
+        <duration>8</duration>
+        <voice>1</voice>
+        <type>whole</type>
+      </note>
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>5</octave>
+        </pitch>
+        <duration>8</duration>
+        <voice>1</voice>
+        <type>whole</type>
+      </note>
+    </measure>
+  </part>
+  <part id="P2">
+    <measure number="1">
+      <attributes>
+        <divisions>2</divisions>
+        <time>
+          <beats>3</beats>
+          <beat-type>4</beat-type>
+        </time>
+        <clef>
+          <sign>G</sign>
+          <line>2</line>
+        </clef>
+      </attributes>
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <backup>
+        <duration>6</duration>
+      </backup>
+    </measure>
+    <measure number="2">
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>eighth</type>
+      </note>
+      <note>
+        <chord />
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>eighth</type>
+      </note>
+      <note>
+        <rest />
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>eighth</type>
+      </note>
+    </measure>
+    <measure number="3">
+      <note>
+        <rest />
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <pitch>
+          <step>A</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+      <note>
+        <pitch>
+          <step>G</step>
+          <octave>4</octave>
+        </pitch>
+        <duration>2</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+      </note>
+    </measure>
+  </part>
+</score-partwise>