diff --git a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureSerializerGenerator.java b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureSerializerGenerator.java
index 8ca3b1bb6..b530a9e66 100644
--- a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureSerializerGenerator.java
+++ b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureSerializerGenerator.java
@@ -55,7 +55,7 @@ public void serializeMembers(${shapeSerializer:T} serializer) {
     private void writeMemberSerialization(JavaWriter writer) {
         boolean isError = shape.hasTrait(ErrorTrait.class);
 
-        for (var member : shape.members()) {
+        for (var member : CodegenUtils.getSortedMembers(shape)) {
             var memberName = symbolProvider.toMemberName(member);
             // if the shape is an error we need to use the `getMessage()` method for message field.
             if (isError && memberName.equalsIgnoreCase("message")) {
diff --git a/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/CollectionStruct.java b/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/CollectionStruct.java
index 4116a3a5c..4f0193681 100644
--- a/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/CollectionStruct.java
+++ b/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/CollectionStruct.java
@@ -200,22 +200,22 @@ public Schema schema() {
 
     @Override
     public void serializeMembers(ShapeSerializer serializer) {
+        serializer.writeList($SCHEMA_SPARSE_LIST, sparseList, sparseList.size(), SharedSerde.SparseStringListSerializer.INSTANCE);
+        serializer.writeMap($SCHEMA_SPARSE_MAP, sparseMap, sparseMap.size(), SharedSerde.SparseStringMapSerializer.INSTANCE);
+        serializer.writeList($SCHEMA_SPARSE_LIST_OF_SPARSE_MAP, sparseListOfSparseMap, sparseListOfSparseMap.size(), SharedSerde.SparseListOfSparseMapSerializer.INSTANCE);
+        serializer.writeList($SCHEMA_NON_SPARSE_LIST_OF_NON_SPARSE_MAP, nonSparseListOfNonSparseMap, nonSparseListOfNonSparseMap.size(), SharedSerde.NonSparseListOfNonSparseMapSerializer.INSTANCE);
         if (nonSparseList != null) {
             serializer.writeList($SCHEMA_NON_SPARSE_LIST, nonSparseList, nonSparseList.size(), SharedSerde.NonSparseStringListSerializer.INSTANCE);
         }
-        serializer.writeList($SCHEMA_SPARSE_LIST, sparseList, sparseList.size(), SharedSerde.SparseStringListSerializer.INSTANCE);
         if (nonSparseMap != null) {
             serializer.writeMap($SCHEMA_NON_SPARSE_MAP, nonSparseMap, nonSparseMap.size(), SharedSerde.NonSparseStringMapSerializer.INSTANCE);
         }
-        serializer.writeMap($SCHEMA_SPARSE_MAP, sparseMap, sparseMap.size(), SharedSerde.SparseStringMapSerializer.INSTANCE);
         if (nonSparseListOfSparseMap != null) {
             serializer.writeList($SCHEMA_NON_SPARSE_LIST_OF_SPARSE_MAP, nonSparseListOfSparseMap, nonSparseListOfSparseMap.size(), SharedSerde.NonSparseListOfSparseMapSerializer.INSTANCE);
         }
-        serializer.writeList($SCHEMA_SPARSE_LIST_OF_SPARSE_MAP, sparseListOfSparseMap, sparseListOfSparseMap.size(), SharedSerde.SparseListOfSparseMapSerializer.INSTANCE);
         if (sparseMapOfNonSparseList != null) {
             serializer.writeMap($SCHEMA_SPARSE_MAP_OF_NON_SPARSE_LIST, sparseMapOfNonSparseList, sparseMapOfNonSparseList.size(), SharedSerde.SparseMapOfNonSparseListSerializer.INSTANCE);
         }
-        serializer.writeList($SCHEMA_NON_SPARSE_LIST_OF_NON_SPARSE_MAP, nonSparseListOfNonSparseMap, nonSparseListOfNonSparseMap.size(), SharedSerde.NonSparseListOfNonSparseMapSerializer.INSTANCE);
     }
 
     @Override
diff --git a/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/JSpecifyStruct.java b/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/JSpecifyStruct.java
index a94fa486b..a95583552 100644
--- a/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/JSpecifyStruct.java
+++ b/codegen/codegen-plugin/src/test/resources/software/amazon/smithy/java/codegen/types/test-cases/jspecify/expected/JSpecifyStruct.java
@@ -103,10 +103,10 @@ public Schema schema() {
     @Override
     public void serializeMembers(ShapeSerializer serializer) {
         serializer.writeString($SCHEMA_REQUIRED_STRING, requiredString);
+        serializer.writeBoolean($SCHEMA_REQUIRED_PRIMITIVE, requiredPrimitive);
         if (optionalString != null) {
             serializer.writeString($SCHEMA_OPTIONAL_STRING, optionalString);
         }
-        serializer.writeBoolean($SCHEMA_REQUIRED_PRIMITIVE, requiredPrimitive);
         if (sparseList != null) {
             serializer.writeList($SCHEMA_SPARSE_LIST, sparseList, sparseList.size(), SharedSerde.SparseStringListSerializer.INSTANCE);
         }