diff --git a/dlt/destinations/impl/postgres/configuration.py b/dlt/destinations/impl/postgres/configuration.py
index 1433d9f641..f1d30a7342 100644
--- a/dlt/destinations/impl/postgres/configuration.py
+++ b/dlt/destinations/impl/postgres/configuration.py
@@ -25,9 +25,6 @@ def parse_native_representation(self, native_value: Any) -> None:
         if not self.is_partial():
             self.resolve()
 
-    def on_resolved(self) -> None:
-        self.database = self.database.lower()
-
     def to_url(self) -> URL:
         url = super().to_url()
         url.update_query_pairs([("connect_timeout", str(self.connect_timeout))])
diff --git a/tests/load/postgres/test_postgres_client.py b/tests/load/postgres/test_postgres_client.py
index 83b59bddaf..daabf6fc51 100644
--- a/tests/load/postgres/test_postgres_client.py
+++ b/tests/load/postgres/test_postgres_client.py
@@ -37,8 +37,10 @@ def test_postgres_credentials_defaults() -> None:
     assert pg_cred.connect_timeout == 15
     assert PostgresCredentials.__config_gen_annotations__ == ["port", "connect_timeout"]
     # port should be optional
-    resolve_configuration(pg_cred, explicit_value="postgres://loader:loader@localhost/dlt_data")
+    resolve_configuration(pg_cred, explicit_value="postgres://loader:loader@localhost/DLT_DATA")
     assert pg_cred.port == 5432
+    # preserve case
+    assert pg_cred.database == "DLT_DATA"
 
 
 def test_postgres_credentials_native_value(environment) -> None:
diff --git a/tests/load/redshift/test_redshift_table_builder.py b/tests/load/redshift/test_redshift_table_builder.py
index 4ad66b6f6b..e280dd94e0 100644
--- a/tests/load/redshift/test_redshift_table_builder.py
+++ b/tests/load/redshift/test_redshift_table_builder.py
@@ -42,7 +42,7 @@ def test_redshift_configuration() -> None:
         }
     ):
         C = resolve_configuration(RedshiftCredentials(), sections=("destination", "my_redshift"))
-        assert C.database == "upper_case_database"
+        assert C.database == "UPPER_CASE_DATABASE"
         assert C.password == "pass"
 
     # check fingerprint