diff --git a/extensions/devservices/mssql/src/main/java/io/quarkus/devservices/mssql/deployment/MSSQLDevServicesProcessor.java b/extensions/devservices/mssql/src/main/java/io/quarkus/devservices/mssql/deployment/MSSQLDevServicesProcessor.java
index 7f32c0dd79b8d..9cc82062f702b 100644
--- a/extensions/devservices/mssql/src/main/java/io/quarkus/devservices/mssql/deployment/MSSQLDevServicesProcessor.java
+++ b/extensions/devservices/mssql/src/main/java/io/quarkus/devservices/mssql/deployment/MSSQLDevServicesProcessor.java
@@ -27,6 +27,11 @@ public class MSSQLDevServicesProcessor {
 
     private static final Logger LOG = Logger.getLogger(MSSQLDevServicesProcessor.class);
 
+    /**
+     * Using SA doesn't work with all collations so let's use the lowercase version instead.
+     */
+    private static final String DEFAULT_USERNAME = "sa";
+
     @BuildStep
     DevServicesDatasourceProviderBuildItem setupMSSQL(
             List<DevServicesSharedNetworkBuildItem> devServicesSharedNetworkBuildItem) {
@@ -63,7 +68,7 @@ public RunningDevServicesDatasource startDatabase(Optional<String> username, Opt
                 return new RunningDevServicesDatasource(container.getContainerId(),
                         container.getEffectiveJdbcUrl(),
                         container.getReactiveUrl(),
-                        container.getUsername(),
+                        DEFAULT_USERNAME,
                         container.getPassword(),
                         new ContainerShutdownCloseable(container, "Microsoft SQL Server"));
             }
diff --git a/extensions/jdbc/jdbc-mssql/deployment/src/test/java/io/quarkus/jdbc/mssql/deployment/DevServicesMsSQLDatasourceTestCase.java b/extensions/jdbc/jdbc-mssql/deployment/src/test/java/io/quarkus/jdbc/mssql/deployment/DevServicesMsSQLDatasourceTestCase.java
index 397da3a1e828a..d580858a70909 100644
--- a/extensions/jdbc/jdbc-mssql/deployment/src/test/java/io/quarkus/jdbc/mssql/deployment/DevServicesMsSQLDatasourceTestCase.java
+++ b/extensions/jdbc/jdbc-mssql/deployment/src/test/java/io/quarkus/jdbc/mssql/deployment/DevServicesMsSQLDatasourceTestCase.java
@@ -41,7 +41,7 @@ public class DevServicesMsSQLDatasourceTestCase {
     public void testDatasource() throws Exception {
         AgroalConnectionPoolConfiguration configuration = dataSource.getConfiguration().connectionPoolConfiguration();
         assertTrue(configuration.connectionFactoryConfiguration().jdbcUrl().contains("jdbc:sqlserver:"));
-        assertEquals("SA", configuration.connectionFactoryConfiguration().principal().getName());
+        assertEquals("sa", configuration.connectionFactoryConfiguration().principal().getName());
         assertEquals(20, configuration.maxSize());
         assertThat(configuration.exceptionSorter()).isInstanceOf(MSSQLExceptionSorter.class);