diff --git a/packages/flutter_tools/lib/src/localizations/gen_l10n_types.dart b/packages/flutter_tools/lib/src/localizations/gen_l10n_types.dart
index 96e9451e00..4be34a3dd4 100644
--- a/packages/flutter_tools/lib/src/localizations/gen_l10n_types.dart
+++ b/packages/flutter_tools/lib/src/localizations/gen_l10n_types.dart
@@ -584,7 +584,9 @@ class Message {
       return x && !y && !z || !x && y && !z || !x && !y && z || !x && !y && !z;
     }
 
-    for (final Placeholder placeholder in templatePlaceholders.values) {
+    for (final Placeholder placeholder in templatePlaceholders.values.followedBy(
+      localePlaceholders.values.expand((Map<String, Placeholder> e) => e.values),
+    )) {
       if (!atMostOneOf(placeholder.isPlural, placeholder.isDateTime, placeholder.isSelect)) {
         throw L10nException('Placeholder is used as plural/select/datetime in certain languages.');
       } else if (placeholder.isPlural) {
diff --git a/packages/flutter_tools/test/general.shard/generate_localizations_test.dart b/packages/flutter_tools/test/general.shard/generate_localizations_test.dart
index 7d3832518d..05a47e334f 100644
--- a/packages/flutter_tools/test/general.shard/generate_localizations_test.dart
+++ b/packages/flutter_tools/test/general.shard/generate_localizations_test.dart
@@ -1689,6 +1689,50 @@ import 'output-localization-file_en.dart' deferred as output-localization-file_e
           expect(content, contains("String get helloWorld => 'Hello {name}'"));
         },
       );
+
+      // Regression test for https://github.com/flutter/flutter/issues/163627
+      //
+      // If placeholders have no explicit type (like `int` or `String`) set
+      // their type can be inferred.
+      //
+      // Later in the pipeline it is ensured that each locales placeholder types
+      // matches the definitions in the template.
+      //
+      // If only the types of the template had been inferred,
+      // and not for the translation there would be a mismatch:
+      // in this case `num` for count and `null` (the default), which is incompatible
+      // and `getSyntheticGeneratedFileContent` would throw an exception.
+      //
+      // This test ensures that both template and locale can be equally partially defined
+      // in the arb.
+      testWithoutContext(
+        'translation placeholder type definitions can be inferred for plurals',
+        () {
+          setupLocalizations(<String, String>{
+            'en': '''
+{
+  "helloWorld": "{count, plural, one{Hello World!} other{Hello Worlds!}}",
+  "@helloWorld": {
+    "description": "The conventional newborn programmer greeting",
+    "placeholders": {
+      "count": {}
+    }
+  }
+}''',
+            'de': '''
+{
+  "helloWorld": "{count, plural, one{Hallo Welt!} other{Hallo Welten!}}",
+  "@helloWorld": {
+    "description": "The conventional newborn programmer greeting",
+    "placeholders": {
+      "count": {}
+    }
+  }
+}''',
+          });
+          expect(getSyntheticGeneratedFileContent(locale: 'en'), isA<String>());
+        },
+      );
     });
 
     group('DateTime tests', () {
@@ -2167,7 +2211,7 @@ import 'output-localization-file_en.dart' deferred as output-localization-file_e
                 (L10nException e) => e.message,
                 'message',
                 contains(
-                  'The placeholder, springStartDate, has its "type" resource attribute set to the "null" type in locale "ja", but it is "DateTime" in the template placeholder.',
+                  'The placeholder, springStartDate, has its "type" resource attribute set to the "Object" type in locale "ja", but it is "DateTime" in the template placeholder.',
                 ),
               ),
             ),