diff --git a/app/dashboard/views/custom_alias.py b/app/dashboard/views/custom_alias.py
index e6da8f4b..48137182 100644
--- a/app/dashboard/views/custom_alias.py
+++ b/app/dashboard/views/custom_alias.py
@@ -23,7 +23,6 @@ from app.models import (
     AliasMailbox,
     DomainDeletedAlias,
 )
-from app.utils import get_suffix
 
 signer = TimestampSigner(CUSTOM_ALIAS_SECRET)
 
@@ -54,7 +53,7 @@ def get_available_suffixes(user: User) -> [SuffixInfo]:
     # for each user domain, generate both the domain and a random suffix version
     for custom_domain in user_custom_domains:
         if custom_domain.random_prefix_generation:
-            suffix = "." + get_suffix(user) + "@" + custom_domain.domain
+            suffix = "." + user.get_random_alias_suffix() + "@" + custom_domain.domain
             suffix_info = SuffixInfo(True, suffix, signer.sign(suffix).decode(), False)
             if user.default_alias_custom_domain_id == custom_domain.id:
                 suffixes.insert(0, suffix_info)
@@ -77,7 +76,7 @@ def get_available_suffixes(user: User) -> [SuffixInfo]:
     # then SimpleLogin domain
     for sl_domain in user.get_sl_domains():
         suffix = (
-            ("" if DISABLE_ALIAS_SUFFIX else "." + get_suffix(user))
+            ("" if DISABLE_ALIAS_SUFFIX else "." + user.get_random_alias_suffix())
             + "@"
             + sl_domain.domain
         )
diff --git a/app/models.py b/app/models.py
index 3ca044cf..f1e9f3bb 100644
--- a/app/models.py
+++ b/app/models.py
@@ -24,6 +24,7 @@ from app.config import (
     FIRST_ALIAS_DOMAIN,
     DISABLE_ONBOARDING,
     UNSUBSCRIBER,
+    ALIAS_RANDOM_SUFFIX_LENGTH,
 )
 from app.errors import AliasInTrashError
 from app.extensions import db
@@ -35,7 +36,7 @@ from app.utils import (
     random_string,
     random_words,
     sanitize_email,
-    get_suffix,
+    random_word,
 )
 
 
@@ -758,6 +759,17 @@ class User(db.Model, ModelMixin, UserMixin, PasswordOracle):
             > 0
         )
 
+    def get_random_alias_suffix(self):
+        """Get random suffix for an alias based on user's preference.
+
+
+        Returns:
+            str: the random suffix generated
+        """
+        if self.random_alias_suffix == AliasSuffixEnum.random_string.value:
+            return random_string(ALIAS_RANDOM_SUFFIX_LENGTH, include_digits=True)
+        return random_word()
+
     def __repr__(self):
         return f"<User {self.id} {self.name} {self.email}>"
 
@@ -1147,7 +1159,7 @@ class Alias(db.Model, ModelMixin):
 
         # find the right suffix - avoid infinite loop by running this at max 1000 times
         for i in range(1000):
-            suffix = get_suffix(user)
+            suffix = user.get_random_alias_suffix()
             email = f"{prefix}.{suffix}@{FIRST_ALIAS_DOMAIN}"
 
             if not cls.get_by(email=email) and not DeletedAlias.get_by(email=email):
diff --git a/app/utils.py b/app/utils.py
index 743c0dea..10e3ab67 100644
--- a/app/utils.py
+++ b/app/utils.py
@@ -4,9 +4,8 @@ import urllib.parse
 
 from unidecode import unidecode
 
-from .config import WORDS_FILE_PATH, ALIAS_RANDOM_SUFFIX_LENGTH
+from .config import WORDS_FILE_PATH
 from .log import LOG
-from .models import User, AliasSuffixEnum
 
 with open(WORDS_FILE_PATH) as f:
     LOG.d("load words file: %s", WORDS_FILE_PATH)
@@ -17,20 +16,6 @@ def random_word():
     return random.choice(_words)
 
 
-def get_suffix(user: User) -> str:
-    """Get random suffix for an alias based on user's preference.
-
-    Args:
-        user (User): the user who is trying to create an alias
-
-    Returns:
-        str: the random suffix generated
-    """
-    if user.random_alias_suffix == AliasSuffixEnum.random_string.value:
-        return random_string(ALIAS_RANDOM_SUFFIX_LENGTH, include_digits=True)
-    return random_word()
-
-
 def word_exist(word):
     return word in _words