diff --git a/tests/models/address/test_address.py b/tests/models/address/test_address.py
index 3d88df4..2c0856b 100644
--- a/tests/models/address/test_address.py
+++ b/tests/models/address/test_address.py
@@ -3,29 +3,7 @@
 
 from shipengine_sdk.errors import ValidationError
 from shipengine_sdk.models import ErrorCode, ErrorSource, ErrorType
-from shipengine_sdk.models.address import Address
-
-
-def empty_address_lines() -> Address:
-    """Returns an invalid address with empty street list."""
-    return Address(
-        street=list(),
-        city_locality="Boston",
-        state_province="MA",
-        postal_code="02215",
-        country_code="US",
-    )
-
-
-def address_with_too_many_lines() -> Address:
-    """Return an address with too many address lines in the street list."""
-    return Address(
-        street=["4 Jersey St", "ste 200", "1st Floor", "Room B"],
-        city_locality="Boston",
-        state_province="MA",
-        postal_code="02215",
-        country_code="US",
-    )
+from tests.util.test_helpers import address_with_too_many_lines, empty_address_lines
 
 
 def address_line_assertions(err: ValidationError, variant: str) -> None:
@@ -45,7 +23,7 @@ def address_line_assertions(err: ValidationError, variant: str) -> None:
 
 class TestAddress:
     def test_no_address_lines(self):
-        """DX-1033 - Too many address lines in the street list."""
+        """DX-1033/DX-1051 - No address lines in the street list."""
         try:
             empty_address_lines()
         except ValidationError as err:
@@ -54,7 +32,7 @@ def test_no_address_lines(self):
                 empty_address_lines()
 
     def test_address_with_too_many_lines(self):
-        """DX-1034 - Too many address lines."""
+        """DX-1034/DX-1052 - Too many address lines."""
         try:
             address_with_too_many_lines()
         except ValidationError as err:
diff --git a/tests/services/test_normalize_address.py b/tests/services/test_normalize_address.py
index 1ed3f16..b9738e8 100644
--- a/tests/services/test_normalize_address.py
+++ b/tests/services/test_normalize_address.py
@@ -1,13 +1,15 @@
 """Test the normalize address method of the ShipEngine SDK."""
 import re
 
-from shipengine_sdk.errors import ShipEngineError
+from shipengine_sdk.errors import ClientSystemError, ShipEngineError, ValidationError
 from shipengine_sdk.models import Address, ErrorCode, ErrorSource, ErrorType
 
 from ..util.test_helpers import (
+    address_missing_required_fields,
     address_with_errors,
     address_with_single_error,
     address_with_warnings,
+    get_server_side_error,
     multi_line_address,
     non_latin_address,
     normalize_an_address,
@@ -161,3 +163,28 @@ def test_normalize_with_multiple_errors(self) -> None:
                 err.message
                 == "Invalid address.\nInvalid City, State, or Zip\nInsufficient or Incorrect Address Data"
             )
+
+    def test_normalize_missing_city_state_and_postal_code(self) -> None:
+        """DX-1053 & DX-1054 - Missing city, state, and postal code."""
+        try:
+            address_missing_required_fields()
+        except ValidationError as err:
+            assert err.request_id is None
+            assert err.source is ErrorSource.SHIPENGINE.value
+            assert err.error_type is ErrorType.VALIDATION.value
+            assert err.error_code is ErrorCode.FIELD_VALUE_REQUIRED.value
+            assert (
+                err.message
+                == "Invalid address. Either the postal code or the city/locality and state/province must be specified."  # noqa
+            )
+
+    def test_normalize_server_side_error(self) -> None:
+        """DX-1056 - Server-side error."""
+        try:
+            get_server_side_error()
+        except ClientSystemError as err:
+            assert err.request_id is not None
+            assert err.request_id.startswith("req_") is True
+            assert err.source is ErrorSource.SHIPENGINE.value
+            assert err.error_type is ErrorType.SYSTEM.value
+            assert err.error_code is ErrorCode.UNSPECIFIED.value
diff --git a/tests/util/test_helpers.py b/tests/util/test_helpers.py
index f74d07e..79866cf 100644
--- a/tests/util/test_helpers.py
+++ b/tests/util/test_helpers.py
@@ -92,6 +92,28 @@ def valid_canadian_address() -> Address:
     )
 
 
+def empty_address_lines() -> Address:
+    """Returns an invalid address with empty street list."""
+    return Address(
+        street=list(),
+        city_locality="Boston",
+        state_province="MA",
+        postal_code="02215",
+        country_code="US",
+    )
+
+
+def address_with_too_many_lines() -> Address:
+    """Return an address with too many address lines in the street list."""
+    return Address(
+        street=["4 Jersey St", "ste 200", "1st Floor", "Room B"],
+        city_locality="Boston",
+        state_province="MA",
+        postal_code="02215",
+        country_code="US",
+    )
+
+
 def multi_line_address() -> Address:
     """Returns a valid multiline address."""
     return Address(