diff --git a/src/plugins/autotest/boost/boosttestparser.cpp b/src/plugins/autotest/boost/boosttestparser.cpp
index 47b190ecffe..65e5807e7b3 100644
--- a/src/plugins/autotest/boost/boosttestparser.cpp
+++ b/src/plugins/autotest/boost/boosttestparser.cpp
@@ -109,7 +109,7 @@ bool BoostTestParser::processDocument(QPromise<TestParseResultPtr> &promise,
     if (projectParts.isEmpty()) // happens if shutting down while parsing
         return false;
     const CppEditor::ProjectPart::ConstPtr projectPart = projectParts.first();
-    const auto projectFile = FilePath::fromString(projectPart->projectFile);
+    const FilePath &projectFile = projectPart->projectFile;
     const QByteArray &fileContent = getFileContent(fileName);
 
     BoostCodeParser codeParser(fileContent, projectPart->languageFeatures, doc, m_cppSnapshot);
diff --git a/src/plugins/autotest/catch/catchtestparser.cpp b/src/plugins/autotest/catch/catchtestparser.cpp
index 314f54e62bb..7633fcb7474 100644
--- a/src/plugins/autotest/catch/catchtestparser.cpp
+++ b/src/plugins/autotest/catch/catchtestparser.cpp
@@ -123,7 +123,7 @@ bool CatchTestParser::processDocument(QPromise<TestParseResultPtr> &promise,
         return false;
     FilePath proFile;
     const CppEditor::ProjectPart::ConstPtr projectPart = projectParts.first();
-    proFile = FilePath::fromString(projectPart->projectFile);
+    proFile = projectPart->projectFile;
 
     CatchCodeParser codeParser(fileContent, projectPart->languageFeatures);
     const CatchTestCodeLocationList foundTests = codeParser.findTests();
diff --git a/src/plugins/autotest/gtest/gtestparser.cpp b/src/plugins/autotest/gtest/gtestparser.cpp
index 8fc292a9224..5a4ef9555b5 100644
--- a/src/plugins/autotest/gtest/gtestparser.cpp
+++ b/src/plugins/autotest/gtest/gtestparser.cpp
@@ -97,7 +97,7 @@ bool GTestParser::processDocument(QPromise<TestParseResultPtr> &promise,
     const QList<CppEditor::ProjectPart::ConstPtr> &ppList =
         CppEditor::CppModelManager::projectPart(filePath);
     if (!ppList.isEmpty())
-        proFile = FilePath::fromString(ppList.first()->projectFile);
+        proFile = ppList.first()->projectFile;
     else
         return false; // happens if shutting down while parsing
 
diff --git a/src/plugins/autotest/gtest/gtesttreeitem.cpp b/src/plugins/autotest/gtest/gtesttreeitem.cpp
index 280bdfa9160..ec195eabb4b 100644
--- a/src/plugins/autotest/gtest/gtesttreeitem.cpp
+++ b/src/plugins/autotest/gtest/gtesttreeitem.cpp
@@ -500,10 +500,10 @@ QSet<QString> internalTargets(const TestTreeItem &item)
     if (projectParts.isEmpty())
         return CppEditor::CppModelManager::dependingInternalTargets(item.filePath());
     for (const CppEditor::ProjectPart::ConstPtr &projectPart : projectParts) {
-        if (FilePath::fromString(projectPart->projectFile) == item.proFile()
-                && Utils::anyOf(projectPart->files, [&filePath](const CppEditor::ProjectFile &pf) {
-                                return pf.path == filePath;
-        })) {
+        if (projectPart->projectFile == item.proFile()
+            && Utils::anyOf(projectPart->files, [&filePath](const CppEditor::ProjectFile &pf) {
+                   return pf.path == filePath;
+               })) {
             result.insert(projectPart->buildSystemTarget);
             if (projectPart->buildTargetType != ProjectExplorer::BuildTargetType::Executable)
                 result.unite(CppEditor::CppModelManager::dependingInternalTargets(filePath));
diff --git a/src/plugins/autotest/qtest/qttestparser.cpp b/src/plugins/autotest/qtest/qttestparser.cpp
index a74944b7b64..7295b582154 100644
--- a/src/plugins/autotest/qtest/qttestparser.cpp
+++ b/src/plugins/autotest/qtest/qttestparser.cpp
@@ -370,7 +370,7 @@ std::optional<bool> QtTestParser::fillTestCaseData(
 }
 
 QtTestParseResult *QtTestParser::createParseResult(
-        const QString &testCaseName, const TestCaseData &data, const QString &projectFile) const
+    const QString &testCaseName, const TestCaseData &data, const FilePath &projectFile) const
 {
     QtTestParseResult *parseResult = new QtTestParseResult(framework());
     parseResult->itemType = TestTreeItem::TestCase;
@@ -379,7 +379,7 @@ QtTestParseResult *QtTestParser::createParseResult(
     parseResult->displayName = testCaseName;
     parseResult->line = data.line;
     parseResult->column = data.column;
-    parseResult->proFile = FilePath::fromString(projectFile);
+    parseResult->proFile = projectFile;
     parseResult->setRunsMultipleTestcases(data.multipleTestCases);
     QMap<QString, QtTestCodeLocationAndType>::ConstIterator it = data.testFunctions.begin();
     const QMap<QString, QtTestCodeLocationAndType>::ConstIterator end = data.testFunctions.end();
diff --git a/src/plugins/autotest/qtest/qttestparser.h b/src/plugins/autotest/qtest/qttestparser.h
index 9f8c44593f0..f95f823891d 100644
--- a/src/plugins/autotest/qtest/qttestparser.h
+++ b/src/plugins/autotest/qtest/qttestparser.h
@@ -53,8 +53,10 @@ private:
     std::optional<bool> fillTestCaseData(const QString &testCaseName,
                                            const CPlusPlus::Document::Ptr &doc,
                                            TestCaseData &data) const;
-    QtTestParseResult *createParseResult(const QString &testCaseName, const TestCaseData &data,
-                                         const QString &projectFile) const;
+    QtTestParseResult *createParseResult(
+        const QString &testCaseName,
+        const TestCaseData &data,
+        const Utils::FilePath &projectFile) const;
     QHash<Utils::FilePath, TestCases> m_testCases;
     QMultiHash<Utils::FilePath, Utils::FilePath> m_alternativeFiles;
     QSet<Utils::FilePath> m_prefilteredFiles;
diff --git a/src/plugins/autotest/quick/quicktestparser.cpp b/src/plugins/autotest/quick/quicktestparser.cpp
index e67926a262c..c761961b3aa 100644
--- a/src/plugins/autotest/quick/quicktestparser.cpp
+++ b/src/plugins/autotest/quick/quicktestparser.cpp
@@ -260,7 +260,7 @@ bool QuickTestParser::handleQtQuickTest(QPromise<TestParseResultPtr> &promise,
     if (ppList.isEmpty()) // happens if shutting down while parsing
         return false;
     const FilePath cppFileName = document->filePath();
-    const FilePath proFile = FilePath::fromString(ppList.at(0)->projectFile);
+    const FilePath proFile = ppList.at(0)->projectFile;
     {
         QWriteLocker lock(&m_parseLock);
         m_mainCppFiles.insert(cppFileName, proFile);
diff --git a/src/plugins/autotest/quick/quicktesttreeitem.cpp b/src/plugins/autotest/quick/quicktesttreeitem.cpp
index c4adf945872..f6dc1194748 100644
--- a/src/plugins/autotest/quick/quicktesttreeitem.cpp
+++ b/src/plugins/autotest/quick/quicktesttreeitem.cpp
@@ -377,7 +377,7 @@ QSet<QString> internalTargets(const FilePath &proFile)
     for (const CppEditor::ProjectPart::ConstPtr &projectPart : projectInfo->projectParts()) {
         if (projectPart->buildTargetType != ProjectExplorer::BuildTargetType::Executable)
             continue;
-        if (projectPart->projectFile != proFile.path())
+        if (projectPart->projectFile != proFile)
             continue;
         if (Utils::anyOf(projectPart->projectMacros, [](const ProjectExplorer::Macro &macro){
             return macro.type == ProjectExplorer::MacroType::Define &&
diff --git a/src/plugins/autotoolsprojectmanager/autotoolsbuildsystem.cpp b/src/plugins/autotoolsprojectmanager/autotoolsbuildsystem.cpp
index e913ec47e08..3a759cafead 100644
--- a/src/plugins/autotoolsprojectmanager/autotoolsbuildsystem.cpp
+++ b/src/plugins/autotoolsprojectmanager/autotoolsbuildsystem.cpp
@@ -154,7 +154,7 @@ void AutotoolsBuildSystem::makefileParsingFinished(const MakefileParserOutputDat
 
     RawProjectPart rpp;
     rpp.setDisplayName(project()->displayName());
-    rpp.setProjectFileLocation(projectFilePath().toString());
+    rpp.setProjectFileLocation(projectFilePath());
     rpp.setQtVersion(kitInfo.projectPartQtVersion);
     const QStringList cflags = outputData.m_cflags;
     QStringList cxxflags = outputData.m_cxxflags;
diff --git a/src/plugins/cmakeprojectmanager/fileapidataextractor.cpp b/src/plugins/cmakeprojectmanager/fileapidataextractor.cpp
index 43af6c8a143..ab583af3264 100644
--- a/src/plugins/cmakeprojectmanager/fileapidataextractor.cpp
+++ b/src/plugins/cmakeprojectmanager/fileapidataextractor.cpp
@@ -446,8 +446,7 @@ static RawProjectParts generateRawProjectParts(const QFuture<void> &cancelFuture
             }
 
             RawProjectPart rpp;
-            rpp.setProjectFileLocation(
-                t.sourceDir.pathAppended(Constants::CMAKE_LISTS_TXT).toString());
+            rpp.setProjectFileLocation(t.sourceDir.pathAppended(Constants::CMAKE_LISTS_TXT));
             rpp.setBuildSystemTarget(t.name);
             const QString postfix = needPostfix ? QString("_%1_%2").arg(ci.language).arg(count)
                                                 : QString();
diff --git a/src/plugins/compilationdatabaseprojectmanager/compilationdatabaseproject.cpp b/src/plugins/compilationdatabaseprojectmanager/compilationdatabaseproject.cpp
index 2b01a6b9124..93d98593deb 100644
--- a/src/plugins/compilationdatabaseprojectmanager/compilationdatabaseproject.cpp
+++ b/src/plugins/compilationdatabaseprojectmanager/compilationdatabaseproject.cpp
@@ -172,7 +172,7 @@ static RawProjectPart makeRawProjectPart(const FilePath &projectFile,
 
     RawProjectPart rpp;
 
-    rpp.setProjectFileLocation(projectFile.toString());
+    rpp.setProjectFileLocation(projectFile);
     rpp.setBuildSystemTarget(workingDir.path());
     rpp.setDisplayName(filePath.fileName());
     rpp.setFiles({filePath.toFSPathString()});
diff --git a/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp b/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp
index dd62fb1fbf1..badad82f691 100644
--- a/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp
+++ b/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp
@@ -1142,7 +1142,7 @@ QVariant ProjectPartsModel::data(const QModelIndex &index, int role) const
         if (column == PartNameColumn)
             return m_projectPartsList.at(row)->displayName;
         else if (column == PartFilePathColumn)
-            return QDir::toNativeSeparators(m_projectPartsList.at(row)->projectFile);
+            return m_projectPartsList.at(row)->projectFile.nativePath();
     } else if (role == Qt::ForegroundRole) {
         if (!m_projectPartsList.at(row)->selectedForBuilding) {
             return QApplication::palette().color(QPalette::ColorGroup::Disabled,
diff --git a/src/plugins/cppeditor/cppparsecontext.cpp b/src/plugins/cppeditor/cppparsecontext.cpp
index 554c6ca8390..9721bccdc29 100644
--- a/src/plugins/cppeditor/cppparsecontext.cpp
+++ b/src/plugins/cppeditor/cppparsecontext.cpp
@@ -105,7 +105,7 @@ QVariant ParseContextModel::data(const QModelIndex &index, int role) const
     if (role == Qt::DisplayRole)
         return m_projectParts[row]->displayName;
     else if (role == Qt::ToolTipRole)
-        return QDir::toNativeSeparators(m_projectParts[row]->projectFile);
+        return m_projectParts[row]->projectFile.nativePath();
 
     return QVariant();
 }
diff --git a/src/plugins/cppeditor/projectinfo_test.cpp b/src/plugins/cppeditor/projectinfo_test.cpp
index 3536c139106..f1035dd7fa0 100644
--- a/src/plugins/cppeditor/projectinfo_test.cpp
+++ b/src/plugins/cppeditor/projectinfo_test.cpp
@@ -115,7 +115,7 @@ void ProjectPartChooserTest::testChooseManuallySet()
     rpp2.setProjectFileLocation("someId");
     ProjectPart::ConstPtr p2 = ProjectPart::create({}, rpp2);
     ProjectPartChooserTestHelper t;
-    t.preferredProjectPartId = p2->projectFile;
+    t.preferredProjectPartId = p2->projectFile.toString();
     t.projectPartsForFile += {p1, p2};
 
     QCOMPARE(t.choose().projectPart, p2);
@@ -128,7 +128,7 @@ void ProjectPartChooserTest::testIndicateManuallySet()
     rpp2.setProjectFileLocation("someId");
     ProjectPart::ConstPtr p2 = ProjectPart::create({}, rpp2);
     ProjectPartChooserTestHelper t;
-    t.preferredProjectPartId = p2->projectFile;
+    t.preferredProjectPartId = p2->projectFile.toString();
     t.projectPartsForFile += {p1, p2};
 
     QVERIFY(t.choose().hints & ProjectPartInfo::IsPreferredMatch);
@@ -141,7 +141,7 @@ void ProjectPartChooserTest::testIndicateManuallySetForFallbackToProjectPartFrom
     rpp2.setProjectFileLocation("someId");
     ProjectPart::ConstPtr p2 = ProjectPart::create({}, rpp2);
     ProjectPartChooserTestHelper t;
-    t.preferredProjectPartId = p2->projectFile;
+    t.preferredProjectPartId = p2->projectFile.toString();
     t.projectPartsFromDependenciesForFile += {p1, p2};
 
     QVERIFY(t.choose().hints & ProjectPartInfo::IsPreferredMatch);
diff --git a/src/plugins/cppeditor/projectpart.cpp b/src/plugins/cppeditor/projectpart.cpp
index 8e4bd1c4fe5..5aed4f19acc 100644
--- a/src/plugins/cppeditor/projectpart.cpp
+++ b/src/plugins/cppeditor/projectpart.cpp
@@ -27,7 +27,7 @@ QString ProjectPart::id() const
 
 QString ProjectPart::projectFileLocation() const
 {
-    QString location = QDir::fromNativeSeparators(projectFile);
+    QString location = projectFile.toString();
     if (projectFileLine > 0)
         location += ":" + QString::number(projectFileLine);
     if (projectFileColumn > 0)
diff --git a/src/plugins/cppeditor/projectpart.h b/src/plugins/cppeditor/projectpart.h
index d3a96ab60c6..88c67762eb6 100644
--- a/src/plugins/cppeditor/projectpart.h
+++ b/src/plugins/cppeditor/projectpart.h
@@ -54,7 +54,7 @@ public:
 
     const Utils::FilePath topLevelProject;
     const QString displayName;
-    const QString projectFile;
+    const Utils::FilePath projectFile;
     const QString projectConfigFile; // Generic Project Manager only
 
     const int projectFileLine = -1;
diff --git a/src/plugins/cppeditor/quickfixes/bringidentifierintoscope.cpp b/src/plugins/cppeditor/quickfixes/bringidentifierintoscope.cpp
index 157f48894d1..9b34a09628c 100644
--- a/src/plugins/cppeditor/quickfixes/bringidentifierintoscope.cpp
+++ b/src/plugins/cppeditor/quickfixes/bringidentifierintoscope.cpp
@@ -398,7 +398,7 @@ private:
                     FileType fileType = node && node->asFileNode() ? node->asFileNode()->fileType()
                                                                    : FileType::Unknown;
                     if (fileType == FileType::Unknown
-                        && ProjectFile::isHeader(ProjectFile::classify(interface.filePath().toString()))) {
+                        && ProjectFile::isHeader(ProjectFile::classify(interface.filePath()))) {
                         fileType = FileType::Header;
                     }
                     if (fileType == FileType::Header) {
diff --git a/src/plugins/genericprojectmanager/genericproject.cpp b/src/plugins/genericprojectmanager/genericproject.cpp
index 634f6482a12..81543685cdf 100644
--- a/src/plugins/genericprojectmanager/genericproject.cpp
+++ b/src/plugins/genericprojectmanager/genericproject.cpp
@@ -565,7 +565,7 @@ void GenericBuildSystem::refreshCppCodeModel()
 
     RawProjectPart rpp;
     rpp.setDisplayName(project()->displayName());
-    rpp.setProjectFileLocation(projectFilePath().toString());
+    rpp.setProjectFileLocation(projectFilePath());
     rpp.setQtVersion(kitInfo.projectPartQtVersion);
     rpp.setHeaderPaths(m_projectIncludePaths);
     rpp.setConfigFileName(m_configFileName);
diff --git a/src/plugins/mesonprojectmanager/mesonprojectparser.cpp b/src/plugins/mesonprojectmanager/mesonprojectparser.cpp
index 006f4ad57a2..07eb419a122 100644
--- a/src/plugins/mesonprojectmanager/mesonprojectparser.cpp
+++ b/src/plugins/mesonprojectmanager/mesonprojectparser.cpp
@@ -310,7 +310,7 @@ RawProjectPart MesonProjectParser::buildRawPart(
     CompilerArgs flags = splitArgs(sources.parameters);
     part.setMacros(flags.macros);
     part.setIncludePaths(toAbsolutePath(m_buildDir, flags.includePaths));
-    part.setProjectFileLocation(target.definedIn);
+    part.setProjectFileLocation(FilePath::fromUserInput(target.definedIn));
     if (sources.language == "cpp")
         part.setFlagsForCxx({cxxToolchain, flags.args, {}});
     else if (sources.language == "c")
diff --git a/src/plugins/projectexplorer/rawprojectpart.cpp b/src/plugins/projectexplorer/rawprojectpart.cpp
index 9bb69c5e846..c98bbea4b42 100644
--- a/src/plugins/projectexplorer/rawprojectpart.cpp
+++ b/src/plugins/projectexplorer/rawprojectpart.cpp
@@ -63,7 +63,7 @@ HeaderPath RawProjectPart::frameworkDetectionHeuristic(const HeaderPath &header)
     return header;
 }
 
-void RawProjectPart::setProjectFileLocation(const QString &projectFile, int line, int column)
+void RawProjectPart::setProjectFileLocation(const Utils::FilePath &projectFile, int line, int column)
 {
     this->projectFile = projectFile;
     projectFileLine = line;
diff --git a/src/plugins/projectexplorer/rawprojectpart.h b/src/plugins/projectexplorer/rawprojectpart.h
index 55729e8e91f..c5ca8a08a5c 100644
--- a/src/plugins/projectexplorer/rawprojectpart.h
+++ b/src/plugins/projectexplorer/rawprojectpart.h
@@ -50,7 +50,7 @@ class PROJECTEXPLORER_EXPORT RawProjectPart
 public:
     void setDisplayName(const QString &displayName);
 
-    void setProjectFileLocation(const QString &projectFile, int line = -1, int column = -1);
+    void setProjectFileLocation(const Utils::FilePath &projectFile, int line = -1, int column = -1);
     void setConfigFileName(const QString &configFileName);
     void setCallGroupId(const QString &id);
 
@@ -79,7 +79,7 @@ public:
 public:
     QString displayName;
 
-    QString projectFile;
+    Utils::FilePath projectFile;
     int projectFileLine = -1;
     int projectFileColumn = -1;
     QString callGroupId;
diff --git a/src/plugins/qbsprojectmanager/qbsproject.cpp b/src/plugins/qbsprojectmanager/qbsproject.cpp
index 2f6bf2cba23..e487107ad12 100644
--- a/src/plugins/qbsprojectmanager/qbsproject.cpp
+++ b/src/plugins/qbsprojectmanager/qbsproject.cpp
@@ -858,9 +858,10 @@ static RawProjectPart generateProjectPart(
     rpp.setHeaderPaths(headerPaths);
     rpp.setDisplayName(groupName);
     const QJsonObject location = groupOrProduct.value("location").toObject();
-    rpp.setProjectFileLocation(location.value("file-path").toString(),
-                               location.value("line").toInt(),
-                               location.value("column").toInt());
+    rpp.setProjectFileLocation(
+        FilePath::fromUserInput(location.value("file-path").toString()),
+        location.value("line").toInt(),
+        location.value("column").toInt());
     rpp.setBuildSystemTarget(QbsProductNode::getBuildKey(product));
     if (product.value("is-runnable").toBool()) {
         rpp.setBuildTargetType(BuildTargetType::Executable);
diff --git a/src/plugins/qmakeprojectmanager/qmakeproject.cpp b/src/plugins/qmakeprojectmanager/qmakeproject.cpp
index 53e80f482b2..e43681ab901 100644
--- a/src/plugins/qmakeprojectmanager/qmakeproject.cpp
+++ b/src/plugins/qmakeprojectmanager/qmakeproject.cpp
@@ -324,7 +324,7 @@ void QmakeBuildSystem::updateCppCodeModel()
         warnOnToolChainMismatch(pro);
         RawProjectPart rpp;
         rpp.setDisplayName(pro->displayName());
-        rpp.setProjectFileLocation(pro->filePath().toString());
+        rpp.setProjectFileLocation(pro->filePath());
         rpp.setBuildSystemTarget(pro->filePath().toString());
         switch (pro->projectType()) {
         case ProjectType::ApplicationTemplate: