diff --git a/system/Helpers/url_helper.php b/system/Helpers/url_helper.php
index 1d03132d82cf..d68fea2aad7d 100644
--- a/system/Helpers/url_helper.php
+++ b/system/Helpers/url_helper.php
@@ -351,7 +351,7 @@ function safe_mailto(string $email, string $title = '', $attributes = ''): strin
     function auto_link(string $str, string $type = 'both', bool $popup = false): string
     {
         // Find and replace any URLs.
-        if ($type !== 'email' && preg_match_all('#(\w*://|www\.)[^\s()<>;]+\w#i', $str, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
+        if ($type !== 'email' && preg_match_all('#(\w*://|www\.)[a-z0-9]+(-+[a-z0-9]+)*(\.[a-z0-9]+(-+[a-z0-9]+)*)+(/([^\s()<>;]+\w)?/?)?#i', $str, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
             // Set our target HTML if using popup links.
             $target = ($popup) ? ' target="_blank"' : '';
 
diff --git a/tests/system/Helpers/URLHelper/MiscUrlTest.php b/tests/system/Helpers/URLHelper/MiscUrlTest.php
index 125356e7d0ed..219b5322dbb5 100644
--- a/tests/system/Helpers/URLHelper/MiscUrlTest.php
+++ b/tests/system/Helpers/URLHelper/MiscUrlTest.php
@@ -533,6 +533,10 @@ public static function provideAutoLinkUrl(): iterable
                 'Visit www.example.com or email foo@bar.com',
                 'Visit <a href="http://www.example.com">www.example.com</a> or email foo@bar.com',
             ],
+            'trailing slash' => [
+                'Trailing slash: https://codeigniter.com/ fubar',
+                'Trailing slash: <a href="https://codeigniter.com/">https://codeigniter.com/</a> fubar',
+            ],
         ];
     }
 
@@ -629,6 +633,10 @@ public static function provideAutolinkBoth(): iterable
                 'Visit www.example.com or email foo@bar.com',
                 "Visit <a href=\"http://www.example.com\">www.example.com</a> or email <script>var l=new Array();l[0] = '>';l[1] = 'a';l[2] = '/';l[3] = '<';l[4] = '|109';l[5] = '|111';l[6] = '|99';l[7] = '|46';l[8] = '|114';l[9] = '|97';l[10] = '|98';l[11] = '|64';l[12] = '|111';l[13] = '|111';l[14] = '|102';l[15] = '>';l[16] = '\"';l[17] = '|109';l[18] = '|111';l[19] = '|99';l[20] = '|46';l[21] = '|114';l[22] = '|97';l[23] = '|98';l[24] = '|64';l[25] = '|111';l[26] = '|111';l[27] = '|102';l[28] = ':';l[29] = 'o';l[30] = 't';l[31] = 'l';l[32] = 'i';l[33] = 'a';l[34] = 'm';l[35] = '\"';l[36] = '=';l[37] = 'f';l[38] = 'e';l[39] = 'r';l[40] = 'h';l[41] = ' ';l[42] = 'a';l[43] = '<';for (var i = l.length-1; i >= 0; i=i-1) {if (l[i].substring(0, 1) === '|') document.write(\"&#\"+unescape(l[i].substring(1))+\";\");else document.write(unescape(l[i]));}</script>",
             ],
+            'email starting with "www."' => [
+                'this is some text that includes www.email@domain.com which is causing an issue',
+                'this is some text that includes ' . safe_mailto('www.email@domain.com') . ' which is causing an issue',
+            ],
         ];
     }
 
diff --git a/user_guide_src/source/changelogs/v4.5.5.rst b/user_guide_src/source/changelogs/v4.5.5.rst
index f6799e484ebf..aaea324399af 100644
--- a/user_guide_src/source/changelogs/v4.5.5.rst
+++ b/user_guide_src/source/changelogs/v4.5.5.rst
@@ -30,6 +30,10 @@ Deprecations
 Bugs Fixed
 **********
 
+- **URL Helper:** The bug where the regular expression in :php:func:`auto_link()`
+  was old has been fixed. As a result of this fix, the same regular expression as
+  CodeIgniter 3 is now used.
+
 See the repo's
 `CHANGELOG.md <https://github.com/codeigniter4/CodeIgniter4/blob/develop/CHANGELOG.md>`_
 for a complete list of bugs fixed.