diff --git a/src/Analyser/FileAnalysisProvider.php b/src/Analyser/FileAnalysisProvider.php
index 53c2277..afe7092 100644
--- a/src/Analyser/FileAnalysisProvider.php
+++ b/src/Analyser/FileAnalysisProvider.php
@@ -253,8 +253,12 @@ private function fileState(array $nodes): array
             if (($node instanceof Namespace_ || $node instanceof Declare_) && $node->stmts !== null) {
                 $state           = $this->fileState($node->stmts);
                 $declaresSymbols = $declaresSymbols || $state['declaresSymbols'];
-                $hasSideEffects  = $hasSideEffects || $state['hasSideEffects'];
-                $sideEffectLine  = $state['hasSideEffects'] ? $state['sideEffectLine'] : $sideEffectLine;
+
+                if (! $hasSideEffects && $state['hasSideEffects']) {
+                    $sideEffectLine = $state['sideEffectLine'];
+                }
+
+                $hasSideEffects = $hasSideEffects || $state['hasSideEffects'];
 
                 continue;
             }
@@ -273,8 +277,11 @@ private function fileState(array $nodes): array
                 continue;
             }
 
+            if (! $hasSideEffects) {
+                $sideEffectLine = $node->getStartLine();
+            }
+
             $hasSideEffects = true;
-            $sideEffectLine = $node->getStartLine();
         }
 
         return [
diff --git a/tests/Analyser/FileAnalysisProviderTest.php b/tests/Analyser/FileAnalysisProviderTest.php
index b69d0f4..85d951c 100644
--- a/tests/Analyser/FileAnalysisProviderTest.php
+++ b/tests/Analyser/FileAnalysisProviderTest.php
@@ -187,6 +187,44 @@ final class Foo {}
         $this->assertSame(4, $fileAnalysis->sideEffectLine);
     }
 
+    public function testReportsFirstSideEffectLineWhenMultipleSideEffectsExist(): void
+    {
+        $file = $this->source(<<<'PHP'
+            <?php
+
+            final class Foo {}
+            echo 'first side effect';
+            echo 'second side effect';
+            echo 'third side effect';
+            PHP);
+
+        $fileAnalysis = (new FileAnalysisProvider())->analyse($file);
+
+        $this->assertTrue($fileAnalysis->declaresSymbols);
+        $this->assertTrue($fileAnalysis->hasSideEffects);
+        $this->assertSame(4, $fileAnalysis->sideEffectLine);
+    }
+
+    public function testKeepsFirstSideEffectLineAcrossNamespaceBlocks(): void
+    {
+        $file = $this->source(<<<'PHP'
+            <?php
+
+            namespace First {
+                echo 'first side effect';
+            }
+
+            namespace Second {
+                echo 'second side effect';
+            }
+            PHP);
+
+        $fileAnalysis = (new FileAnalysisProvider())->analyse($file);
+
+        $this->assertTrue($fileAnalysis->hasSideEffects);
+        $this->assertSame(4, $fileAnalysis->sideEffectLine);
+    }
+
     public function testRejectsConditionalDeclarationsWithBranchesOrSideEffects(): void
     {
         $elseIfFile = $this->source(<<<'PHP'