diff --git a/kotlin/reflect/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapter.kt b/kotlin/reflect/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapter.kt
index f4a01ac6c..824e6a534 100644
--- a/kotlin/reflect/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapter.kt
+++ b/kotlin/reflect/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapter.kt
@@ -28,6 +28,7 @@ import com.squareup.moshi.internal.Util.resolve
 import com.squareup.moshi.rawType
 import java.lang.reflect.Modifier
 import java.lang.reflect.Type
+import java.util.TreeMap
 import kotlin.reflect.KClass
 import kotlin.reflect.KFunction
 import kotlin.reflect.KMutableProperty1
@@ -230,7 +231,7 @@ public class KotlinJsonAdapterFactory : JsonAdapter.Factory {
     val parametersByName = constructor.parameters.associateBy { it.name }
     constructor.isAccessible = true
 
-    val bindingsByName = LinkedHashMap<String, KotlinJsonAdapter.Binding<Any, Any?>>()
+    val bindingsByName = TreeMap<String, KotlinJsonAdapter.Binding<Any, Any?>>()
 
     for (property in rawTypeKotlin.memberProperties) {
       val parameter = parametersByName[property.name]
diff --git a/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapterTest.kt b/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapterTest.kt
index 3a0424bf4..bacf61655 100644
--- a/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapterTest.kt
+++ b/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapterTest.kt
@@ -391,7 +391,7 @@ class KotlinJsonAdapterTest {
     val encoded = SubtypeProperties()
     encoded.a = 3
     encoded.b = 5
-    assertThat(jsonAdapter.toJson(encoded)).isEqualTo("""{"b":5,"a":3}""")
+    assertThat(jsonAdapter.toJson(encoded)).isEqualTo("""{"a":3,"b":5}""")
 
     val decoded = jsonAdapter.fromJson("""{"a":4,"b":6}""")!!
     assertThat(decoded.a).isEqualTo(4)