diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
index 01e35f42ece..e64f252ad7b 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
@@ -24777,6 +24777,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
                 runTest("compiler/testData/diagnostics/tests/multiplatform/actualTypealias_defaultParamsIncompatibility.kt");
             }
 
+            @Test
+            @TestMetadata("actualWithoutExpectWhenExpectIsFakeOverride.kt")
+            public void testActualWithoutExpectWhenExpectIsFakeOverride() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt");
+            }
+
             @Test
             public void testAllFilesPresentInMultiplatform() throws Exception {
                 KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multiplatform"), Pattern.compile("^(.+)\\.(kt|kts)$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
index f060224dbf6..84e4f9d2a8a 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
@@ -24777,6 +24777,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
                 runTest("compiler/testData/diagnostics/tests/multiplatform/actualTypealias_defaultParamsIncompatibility.kt");
             }
 
+            @Test
+            @TestMetadata("actualWithoutExpectWhenExpectIsFakeOverride.kt")
+            public void testActualWithoutExpectWhenExpectIsFakeOverride() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt");
+            }
+
             @Test
             public void testAllFilesPresentInMultiplatform() throws Exception {
                 KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multiplatform"), Pattern.compile("^(.+)\\.(kt|kts)$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithLightTreeTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithLightTreeTestGenerated.java
index 1074010b406..f2d1640806d 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithLightTreeTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithLightTreeTestGenerated.java
@@ -62,6 +62,12 @@ public class FirOldFrontendMPPDiagnosticsWithLightTreeTestGenerated extends Abst
         runTest("compiler/testData/diagnostics/tests/multiplatform/actualTypealias_defaultParamsIncompatibility.kt");
     }
 
+    @Test
+    @TestMetadata("actualWithoutExpectWhenExpectIsFakeOverride.kt")
+    public void testActualWithoutExpectWhenExpectIsFakeOverride() throws Exception {
+        runTest("compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt");
+    }
+
     @Test
     public void testAllFilesPresentInMultiplatform() throws Exception {
         KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multiplatform"), Pattern.compile("^(.*)\\.kts?$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), TargetBackend.JVM_IR, true);
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithPsiTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithPsiTestGenerated.java
index de3e49ab78e..1bdd7465dc4 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithPsiTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendMPPDiagnosticsWithPsiTestGenerated.java
@@ -62,6 +62,12 @@ public class FirOldFrontendMPPDiagnosticsWithPsiTestGenerated extends AbstractFi
         runTest("compiler/testData/diagnostics/tests/multiplatform/actualTypealias_defaultParamsIncompatibility.kt");
     }
 
+    @Test
+    @TestMetadata("actualWithoutExpectWhenExpectIsFakeOverride.kt")
+    public void testActualWithoutExpectWhenExpectIsFakeOverride() throws Exception {
+        runTest("compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt");
+    }
+
     @Test
     public void testAllFilesPresentInMultiplatform() throws Exception {
         KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multiplatform"), Pattern.compile("^(.*)\\.kts?$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), TargetBackend.JVM_IR, true);
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExpectActualDeclarationChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExpectActualDeclarationChecker.kt
index 98e8e5cef82..d48334827eb 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExpectActualDeclarationChecker.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExpectActualDeclarationChecker.kt
@@ -174,7 +174,10 @@ object FirExpectActualDeclarationChecker : FirBasicDeclarationChecker(MppChecker
                 reportClassScopesIncompatibility(symbol, expectedSingleCandidate, declaration, checkingCompatibility, reporter, source, context)
             }
 
-            ExpectActualMatchingCompatibility.MatchedSuccessfully !in matchingCompatibilityToMembersMap -> {
+            ExpectActualMatchingCompatibility.MatchedSuccessfully !in matchingCompatibilityToMembersMap ||
+                    expectedSingleCandidate != null &&
+                    declaration.hasActualModifier() &&
+                    expectedSingleCandidate.isFakeOverride(expectContainingClass, expectActualMatchingContext) -> {
                 reporter.reportOn(
                     source,
                     FirErrors.ACTUAL_WITHOUT_EXPECT,
diff --git a/compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.fir.kt b/compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.fir.kt
new file mode 100644
index 00000000000..aae0305138a
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.fir.kt
@@ -0,0 +1,33 @@
+// MODULE: m1-common
+// FILE: common.kt
+
+fun foo() {}
+class Foo
+
+open class Base {
+    open fun foo() {}
+}
+expect class Bar : Base {
+}
+
+expect open class ExpectBase {
+    open fun foo()
+}
+expect class Baz : ExpectBase
+
+// MODULE: m1-jvm()()(m1-common)
+// FILE: jvm.kt
+
+actual fun <!ACTUAL_WITHOUT_EXPECT!>foo<!>() {}
+actual class <!ACTUAL_WITHOUT_EXPECT!>Foo<!>
+
+actual class Bar : Base() {
+    actual override fun <!ACTUAL_WITHOUT_EXPECT!>foo<!>() {}
+}
+
+actual open class ExpectBase {
+    actual open fun foo() {}
+}
+actual class Baz : ExpectBase() {
+    actual override fun <!ACTUAL_WITHOUT_EXPECT!>foo<!>() {}
+}
diff --git a/compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt b/compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt
new file mode 100644
index 00000000000..897148bc5d9
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt
@@ -0,0 +1,33 @@
+// MODULE: m1-common
+// FILE: common.kt
+
+<!CONFLICTING_OVERLOADS{JVM}!>fun foo()<!> {}
+class <!PACKAGE_OR_CLASSIFIER_REDECLARATION{JVM}!>Foo<!>
+
+open class Base {
+    open fun foo() {}
+}
+expect class Bar : Base {
+}
+
+expect open class ExpectBase {
+    open fun foo()
+}
+expect class Baz : ExpectBase
+
+// MODULE: m1-jvm()()(m1-common)
+// FILE: jvm.kt
+
+<!CONFLICTING_OVERLOADS!>actual fun <!ACTUAL_WITHOUT_EXPECT!>foo<!>()<!> {}
+actual class <!ACTUAL_WITHOUT_EXPECT, PACKAGE_OR_CLASSIFIER_REDECLARATION!>Foo<!>
+
+actual class Bar : Base() {
+    actual override fun <!ACTUAL_WITHOUT_EXPECT!>foo<!>() {}
+}
+
+actual open class ExpectBase {
+    actual open fun foo() {}
+}
+actual class Baz : ExpectBase() {
+    actual override fun <!ACTUAL_WITHOUT_EXPECT!>foo<!>() {}
+}
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
index 36da918d95c..9403a29c4e9 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
@@ -24777,6 +24777,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/multiplatform/actualTypealias_defaultParamsIncompatibility.kt");
             }
 
+            @Test
+            @TestMetadata("actualWithoutExpectWhenExpectIsFakeOverride.kt")
+            public void testActualWithoutExpectWhenExpectIsFakeOverride() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/actualWithoutExpectWhenExpectIsFakeOverride.kt");
+            }
+
             @Test
             public void testAllFilesPresentInMultiplatform() throws Exception {
                 KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multiplatform"), Pattern.compile("^(.*)\\.kts?$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);