diff --git a/app/api/views/alias_options.py b/app/api/views/alias_options.py
index d17bee24..f6ad5301 100644
--- a/app/api/views/alias_options.py
+++ b/app/api/views/alias_options.py
@@ -3,7 +3,9 @@ from sqlalchemy import desc
 
 from app.api.base import api_bp, require_api_auth
 from app.config import ALIAS_DOMAINS, DISABLE_ALIAS_SUFFIX
-from app.dashboard.views.custom_alias import available_suffixes
+from app.dashboard.views.custom_alias import (
+    available_suffixes_more_info,
+)
 from app.extensions import db
 from app.log import LOG
 from app.models import AliasUsedOn, Alias, User
@@ -299,11 +301,10 @@ def options_v4():
             domain_name = convert_to_id(domain_name)
         ret["prefix_suggestion"] = domain_name
 
-    # List of (is_custom_domain, alias-suffix, time-signed alias-suffix)
-    suffixes = available_suffixes(user)
+    suffixes = available_suffixes_more_info(user)
 
     # custom domain should be put first
-    ret["suffixes"] = list([suffix[1], suffix[2]] for suffix in suffixes)
+    ret["suffixes"] = list([suffix.suffix, suffix.signed_suffix] for suffix in suffixes)
 
     return jsonify(ret)
 
@@ -371,12 +372,12 @@ def options_v5():
             domain_name = convert_to_id(domain_name)
         ret["prefix_suggestion"] = domain_name
 
-    # List of (is_custom_domain, alias-suffix, time-signed alias-suffix)
-    suffixes = available_suffixes(user)
+    suffixes = available_suffixes_more_info(user)
 
     # custom domain should be put first
     ret["suffixes"] = [
-        {"suffix": suffix[1], "signed_suffix": suffix[2]} for suffix in suffixes
+        {"suffix": suffix.suffix, "signed_suffix": suffix.signed_suffix}
+        for suffix in suffixes
     ]
 
     return jsonify(ret)
diff --git a/app/oauth/templates/oauth/authorize.html b/app/oauth/templates/oauth/authorize.html
index 26924fea..f62e2d06 100644
--- a/app/oauth/templates/oauth/authorize.html
+++ b/app/oauth/templates/oauth/authorize.html
@@ -109,11 +109,11 @@
                      style="padding-left: 5px">
                   <select class="form-control" name="suffix">
                     {% for suffix in suffixes %}
-                      <option value="{{ suffix[2] }}">
-                        {% if suffix[0] %}
-                          {{ suffix[1] }} (your domain)
+                      <option value="{{ suffix.signed_suffix }}">
+                        {% if suffix.is_custom %}
+                          {{ suffix.suffix }} (your domain)
                         {% else %}
-                          {{ suffix[1] }}
+                          {{ suffix.suffix }}
                         {% endif %}
                       </option>
                     {% endfor %}
diff --git a/app/oauth/views/authorize.py b/app/oauth/views/authorize.py
index 70f59f3d..610e38e3 100644
--- a/app/oauth/views/authorize.py
+++ b/app/oauth/views/authorize.py
@@ -7,7 +7,7 @@ from itsdangerous import SignatureExpired
 
 from app.alias_utils import check_alias_prefix
 from app.config import EMAIL_DOMAIN
-from app.dashboard.views.custom_alias import available_suffixes, signer
+from app.dashboard.views.custom_alias import signer, available_suffixes_more_info
 from app.extensions import db
 from app.jose_utils import make_id_token
 from app.log import LOG
@@ -112,8 +112,7 @@ def authorize():
                 user_custom_domains = [
                     cd.domain for cd in current_user.verified_custom_domains()
                 ]
-                # List of (is_custom_domain, alias-suffix, time-signed alias-suffix)
-                suffixes = available_suffixes(current_user)
+                suffixes = available_suffixes_more_info(current_user)
 
             return render_template(
                 "oauth/authorize.html",
diff --git a/tests/dashboard/test_custom_alias.py b/tests/dashboard/test_custom_alias.py
index 826cb9fa..48e05790 100644
--- a/tests/dashboard/test_custom_alias.py
+++ b/tests/dashboard/test_custom_alias.py
@@ -5,7 +5,7 @@ from app.config import EMAIL_DOMAIN
 from app.dashboard.views.custom_alias import (
     signer,
     verify_prefix_suffix,
-    available_suffixes,
+    available_suffixes_more_info,
 )
 from app.extensions import db
 from app.models import (
@@ -108,13 +108,13 @@ def test_available_suffixes(flask_client):
 
     CustomDomain.create(user_id=user.id, domain="test.com", verified=True)
 
-    assert len(available_suffixes(user)) > 0
+    assert len(available_suffixes_more_info(user)) > 0
 
     # first suffix is custom domain
-    first_suffix = available_suffixes(user)[0]
-    assert first_suffix[0]
-    assert first_suffix[1] == "@test.com"
-    assert first_suffix[2].startswith("@test.com")
+    first_suffix = available_suffixes_more_info(user)[0]
+    assert first_suffix.is_custom
+    assert first_suffix.suffix == "@test.com"
+    assert first_suffix.signed_suffix.startswith("@test.com")
 
 
 def test_available_suffixes_default_domain(flask_client):
@@ -126,13 +126,13 @@ def test_available_suffixes_default_domain(flask_client):
     user.default_alias_public_domain_id = sl_domain.id
 
     # first suffix is SL Domain
-    first_suffix = available_suffixes(user)[0]
-    assert first_suffix[1].endswith(f"@{sl_domain.domain}")
+    first_suffix = available_suffixes_more_info(user)[0]
+    assert first_suffix.suffix.endswith(f"@{sl_domain.domain}")
 
     user.default_alias_public_domain_id = None
     # first suffix is custom domain
-    first_suffix = available_suffixes(user)[0]
-    assert first_suffix[1] == "@test.com"
+    first_suffix = available_suffixes_more_info(user)[0]
+    assert first_suffix.suffix == "@test.com"
 
 
 def test_add_already_existed_alias(flask_client):