diff --git a/netbox/ipam/migrations/0027_ipaddress_add_dns_name.py b/netbox/ipam/migrations/0027_ipaddress_add_dns_name.py
index 534957ce1..4eaa1498d 100644
--- a/netbox/ipam/migrations/0027_ipaddress_add_dns_name.py
+++ b/netbox/ipam/migrations/0027_ipaddress_add_dns_name.py
@@ -14,6 +14,6 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='ipaddress',
             name='dns_name',
-            field=models.CharField(blank=True, max_length=255, validators=[django.core.validators.RegexValidator(code='invalid', message='Only alphanumeric characters, hyphens, and periods are allowed in DNS names', regex='^[0-9A-Za-z.-]+$')]),
+            field=models.CharField(blank=True, max_length=255, validators=[django.core.validators.RegexValidator(code='invalid', message='Only alphanumeric characters, hyphens, periods, and underscores are allowed in DNS names', regex='^[0-9A-Za-z.-_]+$')]),
         ),
     ]