diff --git a/packages/core/schematics/ng-generate/standalone-migration/standalone-bootstrap.ts b/packages/core/schematics/ng-generate/standalone-migration/standalone-bootstrap.ts
index 6d56840d532..b05fda94e06 100644
--- a/packages/core/schematics/ng-generate/standalone-migration/standalone-bootstrap.ts
+++ b/packages/core/schematics/ng-generate/standalone-migration/standalone-bootstrap.ts
@@ -41,6 +41,7 @@ export function toStandaloneBootstrap(
   const languageService = createLanguageService(program, host, rootFileNames, basePath);
   const bootstrapCalls: BootstrapCallAnalysis[] = [];
   const testObjects: ts.ObjectLiteralExpression[] = [];
+  const allDeclarations: Reference<ts.ClassDeclaration>[] = [];
 
   for (const sourceFile of sourceFiles) {
     sourceFile.forEachChild(function walk(node) {
@@ -59,24 +60,19 @@ export function toStandaloneBootstrap(
     testObjects.push(...findTestObjectsToMigrate(sourceFile, typeChecker));
   }
 
-  if (bootstrapCalls.length > 0) {
-    const allDeclarations: Reference<ts.ClassDeclaration>[] = [];
-
-    for (const call of bootstrapCalls) {
-      allDeclarations.push(...call.declarations);
-      migrateBootstrapCall(call, tracker, languageService, typeChecker, printer);
-    }
-
-    if (allDeclarations.length > 0) {
-      // The previous migrations explicitly skip over bootstrapped
-      // declarations so we have to migrate them now.
-      allDeclarations.forEach(
-          decl => convertNgModuleDeclarationToStandalone(
-              decl, allDeclarations, tracker, templateTypeChecker));
-      migrateTestDeclarations(testObjects, allDeclarations, tracker, typeChecker);
-    }
+  for (const call of bootstrapCalls) {
+    allDeclarations.push(...call.declarations);
+    migrateBootstrapCall(call, tracker, languageService, typeChecker, printer);
   }
 
+  // The previous migrations explicitly skip over bootstrapped
+  // declarations so we have to migrate them now.
+  for (const declaration of allDeclarations) {
+    convertNgModuleDeclarationToStandalone(
+        declaration, allDeclarations, tracker, templateTypeChecker);
+  }
+
+  migrateTestDeclarations(testObjects, allDeclarations, tracker, templateTypeChecker, typeChecker);
   return tracker.recordChanges();
 }
 
diff --git a/packages/core/schematics/ng-generate/standalone-migration/to-standalone.ts b/packages/core/schematics/ng-generate/standalone-migration/to-standalone.ts
index 41fa10bfd4b..32c46ab6690 100644
--- a/packages/core/schematics/ng-generate/standalone-migration/to-standalone.ts
+++ b/packages/core/schematics/ng-generate/standalone-migration/to-standalone.ts
@@ -59,7 +59,8 @@ export function toStandalone(
     migrateNgModuleClass(node, declarations, tracker, typeChecker, templateTypeChecker);
   }
 
-  migrateTestDeclarations(testObjectsToMigrate, declarations, tracker, typeChecker);
+  migrateTestDeclarations(
+      testObjectsToMigrate, declarations, tracker, templateTypeChecker, typeChecker);
   return tracker.recordChanges();
 }
 
@@ -167,7 +168,8 @@ function migrateNgModuleClass(
 
   if (metadata) {
     moveDeclarationsToImports(
-        metadata, allDeclarations.map(decl => decl.node), typeChecker, tracker);
+        metadata, allDeclarations.map(decl => decl.node), typeChecker, templateTypeChecker,
+        tracker);
   }
 }
 
@@ -181,7 +183,8 @@ function migrateNgModuleClass(
  */
 function moveDeclarationsToImports(
     literal: ts.ObjectLiteralExpression, allDeclarations: ts.ClassDeclaration[],
-    typeChecker: ts.TypeChecker, tracker: ChangeTracker): void {
+    typeChecker: ts.TypeChecker, templateTypeChecker: TemplateTypeChecker,
+    tracker: ChangeTracker): void {
   const declarationsProp = findLiteralProperty(literal, 'declarations');
 
   if (!declarationsProp) {
@@ -202,7 +205,12 @@ function moveDeclarationsToImports(
         if (ts.isIdentifier(el)) {
           const correspondingClass = findClassDeclaration(el, typeChecker);
 
-          if (!correspondingClass || allDeclarations.includes(correspondingClass)) {
+          if (!correspondingClass ||
+              // Check whether the declaration is either standalone already or is being converted
+              // in this migration. We need to check if it's standalone already, in order to correct
+              // some cases where the main app and the test files are being migrated in separate
+              // programs.
+              isStandaloneDeclaration(correspondingClass, allDeclarations, templateTypeChecker)) {
             declarationsToCopy.push(el);
           } else {
             declarationsToPreserve.push(el);
@@ -502,13 +510,15 @@ export function extractDeclarationsFromModule(
 /**
  * Migrates the `declarations` from a unit test file to standalone.
  * @param testObjects Object literals used to configure the testing modules.
+ * @param declarationsOutsideOfTestFiles Non-testing declarations that are part of this migration.
  * @param tracker
+ * @param templateTypeChecker
  * @param typeChecker
  */
 export function migrateTestDeclarations(
     testObjects: ts.ObjectLiteralExpression[],
     declarationsOutsideOfTestFiles: Reference<ts.ClassDeclaration>[], tracker: ChangeTracker,
-    typeChecker: ts.TypeChecker) {
+    templateTypeChecker: TemplateTypeChecker, typeChecker: ts.TypeChecker) {
   const {decorators, componentImports} = analyzeTestingModules(testObjects, typeChecker);
   const allDeclarations: ts.ClassDeclaration[] =
       declarationsOutsideOfTestFiles.map(ref => ref.node);
@@ -544,7 +554,7 @@ export function migrateTestDeclarations(
   }
 
   for (const obj of testObjects) {
-    moveDeclarationsToImports(obj, allDeclarations, typeChecker, tracker);
+    moveDeclarationsToImports(obj, allDeclarations, typeChecker, templateTypeChecker, tracker);
   }
 }
 
@@ -636,3 +646,21 @@ function extractMetadataLiteral(decorator: ts.Decorator): ts.ObjectLiteralExpres
       decorator.expression.arguments[0] :
       null;
 }
+
+/**
+ * Checks whether a class is a standalone declaration.
+ * @param node Class being checked.
+ * @param declarationsInMigration Classes that are being converted to standalone in this migration.
+ * @param templateTypeChecker
+ */
+function isStandaloneDeclaration(
+    node: ts.ClassDeclaration, declarationsInMigration: ts.ClassDeclaration[],
+    templateTypeChecker: TemplateTypeChecker): boolean {
+  if (declarationsInMigration.includes(node)) {
+    return true;
+  }
+
+  const metadata =
+      templateTypeChecker.getDirectiveMetadata(node) || templateTypeChecker.getPipeMetadata(node);
+  return metadata != null && metadata.isStandalone;
+}
diff --git a/packages/core/schematics/test/standalone_migration_spec.ts b/packages/core/schematics/test/standalone_migration_spec.ts
index 090652a9b93..f6bf92366b4 100644
--- a/packages/core/schematics/test/standalone_migration_spec.ts
+++ b/packages/core/schematics/test/standalone_migration_spec.ts
@@ -930,6 +930,41 @@ describe('standalone migration', () => {
     `));
   });
 
+  it('should migrate tests where the declaration is already standalone', async () => {
+    writeFile('comp.ts', `
+      import {Component} from '@angular/core';
+
+      @Component({selector: 'comp', template: '', standalone: true})
+      export class MyComp {}
+    `);
+
+    writeFile('app.spec.ts', `
+      import {TestBed} from '@angular/core/testing';
+      import {MyComp} from './comp';
+
+      describe('bootrstrapping an app', () => {
+        it('should work', () => {
+          TestBed.configureTestingModule({declarations: [MyComp]});
+          expect(() => TestBed.createComponent(MyComp)).not.toThrow();
+        });
+      });
+    `);
+
+    await runMigration('convert-to-standalone');
+
+    expect(stripWhitespace(tree.readContent('app.spec.ts'))).toContain(stripWhitespace(`
+      import {TestBed} from '@angular/core/testing';
+      import {MyComp} from './comp';
+
+      describe('bootrstrapping an app', () => {
+        it('should work', () => {
+          TestBed.configureTestingModule({imports: [MyComp]});
+          expect(() => TestBed.createComponent(MyComp)).not.toThrow();
+        });
+      });
+    `));
+  });
+
   it('should import the module that declares a template dependency', async () => {
     writeFile('./should-migrate/module.ts', `
       import {NgModule} from '@angular/core';