diff --git a/sd/qa/unit/export-tests-ooxml4.cxx b/sd/qa/unit/export-tests-ooxml4.cxx
index 97116c2dd5f8..99ec6d476e11 100644
--- a/sd/qa/unit/export-tests-ooxml4.cxx
+++ b/sd/qa/unit/export-tests-ooxml4.cxx
@@ -1456,6 +1456,38 @@ CPPUNIT_TEST_FIXTURE(SdOOXMLExportTest4, testTdf157740_slideMasters)
     assertXPath(pXmlDocContent, "/p:sldMaster/p:sldLayoutIdLst/p:sldLayoutId", 7);
 }
 
+CPPUNIT_TEST_FIXTURE(SdOOXMLExportTest4, testNotesMasterThemeNoAfterDeduplicatedMasters)
+{
+    createSdImpressDoc("n759180.pptx");
+    save(TestFilter::PPTX);
+
+    xmlDocUniquePtr pXmlDocContent = parseExport(u"ppt/presentation.xml"_ustr);
+    assertXPath(pXmlDocContent, "/p:presentation/p:sldMasterIdLst/p:sldMasterId", 1);
+
+    xmlDocUniquePtr pXmlDocRels = parseExport(u"ppt/slideMasters/_rels/slideMaster1.xml.rels"_ustr);
+    assertXPath(pXmlDocRels,
+                "/rels:Relationships/rels:Relationship[@Type='http://schemas.openxmlformats.org/"
+                "officeDocument/2006/relationships/theme']",
+                "Target", u"../theme/theme1.xml");
+
+    // The one slide master of this document has 12 layouts, which are imported as 12 master pages
+    // and written back as one slide master. The notes master theme takes the number after the slide
+    // master theme, as in the original file, without a gap for the master pages that were merged.
+    // Without the change in place, this test would have failed with:
+    // - Expected: ../theme/theme2.xml
+    // - Actual  : ../theme/theme13.xml
+    pXmlDocRels = parseExport(u"ppt/notesMasters/_rels/notesMaster1.xml.rels"_ustr);
+    assertXPath(pXmlDocRels,
+                "/rels:Relationships/rels:Relationship[@Type='http://schemas.openxmlformats.org/"
+                "officeDocument/2006/relationships/theme']",
+                "Target", u"../theme/theme2.xml");
+
+    uno::Reference<packages::zip::XZipFileAccess2> xNameAccess
+        = packages::zip::ZipFileAccess::createWithURL(comphelper::getComponentContext(m_xSFactory),
+                                                      maTempFile.GetURL());
+    CPPUNIT_ASSERT_EQUAL(true, bool(xNameAccess->hasByName(u"ppt/theme/theme2.xml"_ustr)));
+}
+
 CPPUNIT_TEST_FIXTURE(SdOOXMLExportTest4, testTdf159931_slideLayouts)
 {
     createSdImpressDoc("odp/repeatBitmapMode.odp");
diff --git a/sd/source/filter/eppt/pptx-epptooxml.cxx b/sd/source/filter/eppt/pptx-epptooxml.cxx
index 9843f5ed8785..4a7152993130 100644
--- a/sd/source/filter/eppt/pptx-epptooxml.cxx
+++ b/sd/source/filter/eppt/pptx-epptooxml.cxx
@@ -3330,12 +3330,12 @@ void PowerPointExport::WriteNotesMaster()
         auto pTheme = std::make_shared<model::Theme>("Office Theme");
         pTheme->setColorSet(std::make_shared<model::ColorSet>(*pDefaultColorSet));
 
-        WriteTheme(mnMasterPages - static_cast<int>(mbHasCanvasPage), pTheme.get());
+        WriteTheme(mnThemeIdMax, pTheme.get());
 
         // add implicit relation to the presentation theme
         addRelation(pFS->getOutputStream(),
                     oox::getRelationship(Relationship::THEME),
-                    Concat2View("../theme/theme" + OUString::number(mnMasterPages + 1 - static_cast<int>(mbHasCanvasPage)) + ".xml"));
+                    Concat2View("../theme/theme" + OUString::number(++mnThemeIdMax) + ".xml"));
     }
 
     pFS->startElementNS(XML_p, XML_notesMaster, presentationNamespaces(*this));