diff --git a/scm-ui/ui-webapp/src/repos/components/form/RepositoryForm.tsx b/scm-ui/ui-webapp/src/repos/components/form/RepositoryForm.tsx
index 091bfdeee8..a841715104 100644
--- a/scm-ui/ui-webapp/src/repos/components/form/RepositoryForm.tsx
+++ b/scm-ui/ui-webapp/src/repos/components/form/RepositoryForm.tsx
@@ -268,7 +268,7 @@ class RepositoryForm extends React.Component<Props, State> {
 
   handleNamespaceChange = (namespace: string) => {
     this.setState({
-      namespaceValidationError: !validator.isNameValid(namespace),
+      namespaceValidationError: !validator.isNamespaceValid(namespace),
       repository: {
         ...this.state.repository,
         namespace
diff --git a/scm-ui/ui-webapp/src/repos/components/form/repositoryValidation.ts b/scm-ui/ui-webapp/src/repos/components/form/repositoryValidation.ts
index b9ff7f6adb..c52a6b5e6f 100644
--- a/scm-ui/ui-webapp/src/repos/components/form/repositoryValidation.ts
+++ b/scm-ui/ui-webapp/src/repos/components/form/repositoryValidation.ts
@@ -25,6 +25,11 @@
 import { validation } from "@scm-manager/ui-components";
 
 const nameRegex = /(?!^\.\.$)(?!^\.$)(?!.*[.]git$)(?!.*[\\\[\]])^[A-Za-z0-9\.][A-Za-z0-9\.\-_]*$/;
+const namespaceExceptionsRegex = /^(([0-9]{1,3})|(create))$/;
+
+export const isNamespaceValid = (name: string) => {
+  return nameRegex.test(name) && !namespaceExceptionsRegex.test(name);
+};
 
 export const isNameValid = (name: string) => {
   return nameRegex.test(name);
diff --git a/scm-webapp/src/main/java/sonia/scm/repository/CustomNamespaceStrategy.java b/scm-webapp/src/main/java/sonia/scm/repository/CustomNamespaceStrategy.java
index c38831ca17..bc28e7104f 100644
--- a/scm-webapp/src/main/java/sonia/scm/repository/CustomNamespaceStrategy.java
+++ b/scm-webapp/src/main/java/sonia/scm/repository/CustomNamespaceStrategy.java
@@ -27,17 +27,25 @@ package sonia.scm.repository;
 import sonia.scm.plugin.Extension;
 import sonia.scm.util.ValidationUtil;
 
+import java.util.regex.Pattern;
+
 import static sonia.scm.ScmConstraintViolationException.Builder.doThrow;
 
 @Extension
 public class CustomNamespaceStrategy implements NamespaceStrategy {
+
+  private static final Pattern ONE_TO_THREE_DIGITS = Pattern.compile("[0-9]{1,3}");
+
   @Override
   public String createNamespace(Repository repository) {
     String namespace = repository.getNamespace();
 
     doThrow()
       .violation("invalid namespace", "namespace")
-      .when(!ValidationUtil.isRepositoryNameValid(namespace) || namespace.matches("[0-9]{1,3}"));
+      .when(
+        !ValidationUtil.isRepositoryNameValid(namespace)
+          || ONE_TO_THREE_DIGITS.matcher(namespace).matches()
+          || namespace.equals("create"));
 
     return namespace;
   }
diff --git a/scm-webapp/src/test/java/sonia/scm/repository/CustomNamespaceStrategyTest.java b/scm-webapp/src/test/java/sonia/scm/repository/CustomNamespaceStrategyTest.java
index 52d48ece75..ab17b4f7b2 100644
--- a/scm-webapp/src/test/java/sonia/scm/repository/CustomNamespaceStrategyTest.java
+++ b/scm-webapp/src/test/java/sonia/scm/repository/CustomNamespaceStrategyTest.java
@@ -21,10 +21,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-    
+
 package sonia.scm.repository;
 
-import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
 import sonia.scm.ScmConstraintViolationException;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -34,19 +35,21 @@ class CustomNamespaceStrategyTest {
 
   private final NamespaceStrategy namespaceStrategy = new CustomNamespaceStrategy();
 
-  @Test
-  void shouldReturnNamespaceFromRepository() {
-    Repository heartOfGold = RepositoryTestData.createHeartOfGold();
-    assertThat(namespaceStrategy.createNamespace(heartOfGold)).isEqualTo(RepositoryTestData.NAMESPACE);
+  @ParameterizedTest
+  @ValueSource(strings = {"valid", "123_", "something_valid", "1234", "create_it"})
+  void shouldReturnNamespaceFromRepository(String expectedValidNamespace) {
+    Repository repository = RepositoryTestData.createHeartOfGold();
+    repository.setNamespace(expectedValidNamespace);
+
+    assertThat(namespaceStrategy.createNamespace(repository)).isEqualTo(expectedValidNamespace);
   }
 
-  @Test
-  void shouldThrowAnValidationExceptionForAnInvalidNamespace() {
-    Repository repository = new Repository();
-    repository.setNamespace("..");
-    repository.setName(".");
+  @ParameterizedTest
+  @ValueSource(strings = {"..", " ", "0", "123", "create"})
+  void shouldThrowAnValidationExceptionForAnInvalidNamespace(String expectedAsInvalidNamespace) {
+    Repository repository = RepositoryTestData.createHeartOfGold();
+    repository.setNamespace(expectedAsInvalidNamespace);
 
     assertThrows(ScmConstraintViolationException.class, () -> namespaceStrategy.createNamespace(repository));
   }
-
 }