diff --git a/wire-java-generator/src/test/java/com/squareup/wire/java/JavaGeneratorTest.java b/wire-java-generator/src/test/java/com/squareup/wire/java/JavaGeneratorTest.java
index 6655b7b89d..d90ecdf993 100644
--- a/wire-java-generator/src/test/java/com/squareup/wire/java/JavaGeneratorTest.java
+++ b/wire-java-generator/src/test/java/com/squareup/wire/java/JavaGeneratorTest.java
@@ -925,11 +925,19 @@ public void usesFieldMask() throws Exception {
                     + "import \"google/protobuf/field_mask.proto\";\n"
                     + "message Message {\n"
                     + "  optional google.protobuf.FieldMask mask = 1;\n"
+                    + "  repeated google.protobuf.FieldMask masks = 2;\n"
+                    + "  map<int32, google.protobuf.FieldMask> masks_by_id = 3;\n"
                     + "}\n")
             .build();
     String code = new JavaWithProfilesGenerator(schema).generateJava("common.proto.Message");
     assertThat(code).contains("import com.squareup.wire.FieldMask;");
+    assertThat(code).contains("public final FieldMask mask;");
+    assertThat(code).contains("public final List<FieldMask> masks;");
+    assertThat(code).contains("public final Map<Integer, FieldMask> masks_by_id;");
     assertThat(code).contains("ProtoAdapter.FIELD_MASK");
+    assertThat(code).contains("ProtoAdapter.FIELD_MASK.asRepeated()");
+    assertThat(code)
+        .contains("ProtoAdapter.newMapAdapter(ProtoAdapter.INT32, ProtoAdapter.FIELD_MASK)");
   }
 
   @Test
diff --git a/wire-kotlin-generator/src/test/java/com/squareup/wire/kotlin/KotlinGeneratorTest.kt b/wire-kotlin-generator/src/test/java/com/squareup/wire/kotlin/KotlinGeneratorTest.kt
index 133e596778..abffb07f8d 100644
--- a/wire-kotlin-generator/src/test/java/com/squareup/wire/kotlin/KotlinGeneratorTest.kt
+++ b/wire-kotlin-generator/src/test/java/com/squareup/wire/kotlin/KotlinGeneratorTest.kt
@@ -1514,13 +1514,24 @@ class KotlinGeneratorTest {
         |import "google/protobuf/field_mask.proto";
         |message Message {
         |  optional google.protobuf.FieldMask mask = 1;
+        |  repeated google.protobuf.FieldMask masks = 2;
+        |  map<int32, google.protobuf.FieldMask> masks_by_id = 3;
         |}
         """.trimMargin(),
       )
     }
     val code = KotlinWithProfilesGenerator(schema).generateKotlin("common.proto.Message")
     assertThat(code).contains("import com.squareup.wire.FieldMask")
+    assertThat(code).contains("public val mask: FieldMask? = null")
+    assertThat(code).contains("masks: List<FieldMask> = emptyList()")
+    assertThat(code).contains("masks_by_id: Map<Int, FieldMask> = emptyMap()")
+    assertThat(code).contains("public val masks: List<FieldMask> = immutableCopyOf(\"masks\", masks)")
+    assertThat(code).contains(
+      "public val masks_by_id: Map<Int, FieldMask> = immutableCopyOf(\"masks_by_id\", masks_by_id)",
+    )
     assertThat(code).contains("ProtoAdapter.FIELD_MASK")
+    assertThat(code).contains("ProtoAdapter.FIELD_MASK.asRepeated()")
+    assertThat(code).contains("ProtoAdapter.newMapAdapter(ProtoAdapter.INT32, ProtoAdapter.FIELD_MASK)")
   }
 
   @Test fun wildCommentsAreEscaped() {