diff --git a/changelogs/fragments/43931-strip-trailing-comments.yml b/changelogs/fragments/43931-strip-trailing-comments.yml
new file mode 100644
index 00000000000..3a32468856d
--- /dev/null
+++ b/changelogs/fragments/43931-strip-trailing-comments.yml
@@ -0,0 +1,2 @@
+bugfixes:
+  - user - Strip trailing comments in /etc/default/passwd (https://github.com/ansible/ansible/pull/43931)
diff --git a/lib/ansible/modules/system/user.py b/lib/ansible/modules/system/user.py
index 6b030c88c18..c0677a2ae19 100644
--- a/lib/ansible/modules/system/user.py
+++ b/lib/ansible/modules/system/user.py
@@ -348,6 +348,7 @@ import pwd
 import shutil
 import socket
 import time
+import re
 
 from ansible.module_utils._text import to_native
 from ansible.module_utils.basic import load_platform_subclass, AnsibleModule
@@ -1525,6 +1526,9 @@ class SunOS(User):
                 line = line.strip()
                 if (line.startswith('#') or line == ''):
                     continue
+                m = re.match(r'^([^#]*)#(.*)$', line)
+                if m:  # The line contains a hash / comment
+                    line = m.group(1)
                 key, value = line.split('=')
                 if key == "MINWEEKS":
                     minweeks = value.rstrip('\n')