diff --git a/core/src/main/java/google/registry/tools/CreateOrUpdateRegistrarCommand.java b/core/src/main/java/google/registry/tools/CreateOrUpdateRegistrarCommand.java
index db52912de..b07f3ef17 100644
--- a/core/src/main/java/google/registry/tools/CreateOrUpdateRegistrarCommand.java
+++ b/core/src/main/java/google/registry/tools/CreateOrUpdateRegistrarCommand.java
@@ -19,12 +19,12 @@ import static com.google.common.base.Strings.isNullOrEmpty;
 import static com.google.common.base.Verify.verify;
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
-import static google.registry.util.DomainNameUtils.canonicalizeHostname;
 import static google.registry.util.RegistrarUtils.normalizeRegistrarName;
 import static java.nio.charset.StandardCharsets.US_ASCII;
 import static org.joda.time.DateTimeZone.UTC;
 
 import com.beust.jcommander.Parameter;
+import com.google.common.base.Ascii;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import google.registry.flows.certs.CertificateChecker;
@@ -305,20 +305,16 @@ abstract class CreateOrUpdateRegistrarCommand extends MutatingCommand {
       if (!allowedTlds.isEmpty()) {
         checkArgument(
             addAllowedTlds.isEmpty(), "Can't specify both --allowedTlds and --addAllowedTlds");
-        ImmutableSet.Builder<String> allowedTldsBuilder = new ImmutableSet.Builder<>();
-        for (String allowedTld : allowedTlds) {
-          allowedTldsBuilder.add(canonicalizeHostname(allowedTld));
-        }
-        builder.setAllowedTlds(allowedTldsBuilder.build());
+        builder.setAllowedTlds(
+            allowedTlds.stream().map(Ascii::toLowerCase).collect(toImmutableSet()));
       }
       if (!addAllowedTlds.isEmpty()) {
         ImmutableSet.Builder<String> allowedTldsBuilder = new ImmutableSet.Builder<>();
         if (oldRegistrar != null) {
           allowedTldsBuilder.addAll(oldRegistrar.getAllowedTlds());
         }
-        for (String allowedTld : addAllowedTlds) {
-          allowedTldsBuilder.add(canonicalizeHostname(allowedTld));
-        }
+        allowedTldsBuilder.addAll(
+            addAllowedTlds.stream().map(Ascii::toLowerCase).collect(toImmutableSet()));
         builder.setAllowedTlds(allowedTldsBuilder.build());
       }
       if (ipAllowList != null) {
diff --git a/core/src/test/java/google/registry/tools/UpdateRegistrarCommandTest.java b/core/src/test/java/google/registry/tools/UpdateRegistrarCommandTest.java
index 9f7265306..796a356db 100644
--- a/core/src/test/java/google/registry/tools/UpdateRegistrarCommandTest.java
+++ b/core/src/test/java/google/registry/tools/UpdateRegistrarCommandTest.java
@@ -124,6 +124,24 @@ class UpdateRegistrarCommandTest extends CommandTestCase<UpdateRegistrarCommand>
         .containsExactly("xn--q9jyb4c", "foobar");
   }
 
+  @Test
+  void testSuccess_allowedTlds_tldNameWithHyphens() throws Exception {
+    persistRdapAbuseContact();
+    createTlds("zz--main-1611", "foobar");
+    persistResource(
+        loadRegistrar("NewRegistrar")
+            .asBuilder()
+            .setAllowedTlds(ImmutableSet.of("foobar"))
+            .build());
+    runCommandInEnvironment(
+        RegistryToolEnvironment.PRODUCTION,
+        "--allowed_tlds=zz--main-1611,foobar",
+        "--force",
+        "NewRegistrar");
+    assertThat(loadRegistrar("NewRegistrar").getAllowedTlds())
+        .containsExactly("zz--main-1611", "foobar");
+  }
+
   @Test
   void testSuccess_addAllowedTlds() throws Exception {
     persistRdapAbuseContact();
@@ -142,6 +160,19 @@ class UpdateRegistrarCommandTest extends CommandTestCase<UpdateRegistrarCommand>
         .containsExactly("xn--q9jyb4c", "foo", "bar");
   }
 
+  @Test
+  void testSuccess_addAllowedTlds_tldNameWithHyphens() throws Exception {
+    persistRdapAbuseContact();
+    createTlds("foo", "bar", "zz--main-1611");
+    runCommandInEnvironment(
+        RegistryToolEnvironment.PRODUCTION,
+        "--add_allowed_tlds=foo,bar",
+        "--force",
+        "NewRegistrar");
+    assertThat(loadRegistrar("NewRegistrar").getAllowedTlds())
+        .containsExactly("foo", "bar", "zz--main-1611");
+  }
+
   @Test
   void testSuccess_addAllowedTldsWithDupes() throws Exception {
     persistRdapAbuseContact();