diff --git a/common/helpers/StringHelper.php b/common/helpers/StringHelper.php
index efa49d9..70d648e 100644
--- a/common/helpers/StringHelper.php
+++ b/common/helpers/StringHelper.php
@@ -1,11 +1,12 @@
 <?php
+declare(strict_types=1);
 namespace common\helpers;
 
 use Ramsey\Uuid\Uuid;
 
 class StringHelper {
 
-    public static function getEmailMask(string $email) : string {
+    public static function getEmailMask(string $email): string {
         $username = explode('@', $email)[0];
         $usernameLength = mb_strlen($username);
         $maskChars = '**';
@@ -29,7 +30,7 @@ class StringHelper {
      * @param string $uuid
      * @return bool
      */
-    public static function isUuid(string $uuid) : bool {
+    public static function isUuid(string $uuid): bool {
         try {
             Uuid::fromString($uuid);
         } catch (\InvalidArgumentException $e) {
@@ -39,4 +40,17 @@ class StringHelper {
         return true;
     }
 
+    /**
+     * Returns a string with whitespace removed from the start and end of the
+     * string. Supports the removal of unicode whitespace.
+     *
+     * Based on the http://markushedlund.com/dev/trim-unicodeutf-8-whitespace-in-php
+     *
+     * @param  string $string string to remove whitespaces
+     * @return string trimmed $string
+     */
+    public static function trim(string $string): string {
+        return preg_replace('/^[\pZ\pC]+|[\pZ\pC]+$/u', '', $string);
+    }
+
 }
diff --git a/common/validators/EmailValidator.php b/common/validators/EmailValidator.php
index 4309352..1a46fe9 100644
--- a/common/validators/EmailValidator.php
+++ b/common/validators/EmailValidator.php
@@ -2,6 +2,7 @@
 namespace common\validators;
 
 use common\helpers\Error as E;
+use common\helpers\StringHelper;
 use common\models\Account;
 use Ely\Yii2\TempmailValidator;
 use yii\base\Model;
@@ -20,7 +21,7 @@ class EmailValidator extends Validator {
     public $skipOnEmpty = false;
 
     public function validateAttribute($model, $attribute) {
-        $filter = new validators\FilterValidator(['filter' => 'trim']);
+        $filter = new validators\FilterValidator(['filter' => [StringHelper::class, 'trim']]);
 
         $required = new validators\RequiredValidator();
         $required->message = E::EMAIL_REQUIRED;
diff --git a/common/validators/UsernameValidator.php b/common/validators/UsernameValidator.php
index 7f5b76d..657bd03 100644
--- a/common/validators/UsernameValidator.php
+++ b/common/validators/UsernameValidator.php
@@ -2,6 +2,7 @@
 namespace common\validators;
 
 use common\helpers\Error as E;
+use common\helpers\StringHelper;
 use common\models\Account;
 use yii\base\Model;
 use yii\db\QueryInterface;
@@ -19,7 +20,7 @@ class UsernameValidator extends Validator {
     public $skipOnEmpty = false;
 
     public function validateAttribute($model, $attribute) {
-        $filter = new validators\FilterValidator(['filter' => 'trim']);
+        $filter = new validators\FilterValidator(['filter' => [StringHelper::class, 'trim']]);
 
         $required = new validators\RequiredValidator();
         $required->message = E::USERNAME_REQUIRED;
diff --git a/tests/codeception/common/unit/helpers/StringHelperTest.php b/tests/codeception/common/unit/helpers/StringHelperTest.php
index b1f1a21..fe6e4bf 100644
--- a/tests/codeception/common/unit/helpers/StringHelperTest.php
+++ b/tests/codeception/common/unit/helpers/StringHelperTest.php
@@ -19,4 +19,42 @@ class StringHelperTest extends \PHPUnit_Framework_TestCase {
         $this->assertFalse(StringHelper::isUuid('12345678'));
     }
 
+    /**
+     * @dataProvider trimProvider()
+     */
+    public function testTrim($expected, $string) {
+        $result = StringHelper::trim($string);
+        $this->assertEquals($expected, $result);
+    }
+
+    /**
+     * http://jkorpela.fi/chars/spaces.html
+     * http://www.alanwood.net/unicode/general_punctuation.html
+     *
+     * @return array
+     */
+    public function trimProvider() {
+        return [
+            ['foo   bar', '  foo   bar  '], // Simple spaces
+            ['foo bar', ' foo bar'], // Only left side space
+            ['foo bar', 'foo bar '], // Only right side space
+            ['foo bar', "\n\t foo bar \n\t"], // New line, tab character and simple space
+            ['fòô   bàř', '  fòô   bàř  '], // UTF-8 text
+            ['fòô bàř', ' fòô bàř'], // Only left side space width UTF-8 text
+            ['fòô bàř', 'fòô bàř '], // Only right side space width UTF-8 text
+            ['fòô bàř', "\n\t fòô bàř \n\t"], // New line, tab character and simple space width UTF-8 string
+            ['fòô', "\u{00a0}fòô\u{00a0}"], // No-break space (U+00A0)
+            ['fòô', "\u{1680}fòô\u{1680}"], // Ogham space mark (U+1680)
+            ['fòô', "\u{180e}fòô\u{180e}"], // Mongolian vowel separator (U+180E)
+            ['fòô', "\u{2000}\u{2001}\u{2002}\u{2003}\u{2004}\u{2005}\u{2006}\u{2007}fòô"], // Spaces U+2000 to U+2007
+            ['fòô', "\u{2008}\u{2009}\u{200a}\u{200b}\u{200c}\u{200d}\u{200e}\u{200f}fòô"], // Spaces U+2008 to U+200F
+            ['fòô', "\u{2028}\u{2029}\u{202a}\u{202b}\u{202c}\u{202d}\u{202e}\u{202f}fòô"], // Spaces U+2028 to U+202F
+            ['fòô', "\u{2060}\u{2061}\u{2062}\u{2063}\u{2064}\u{2065}\u{2066}\u{2067}fòô"], // Spaces U+2060 to U+2067
+            ['fòô', "\u{2068}\u{2069}\u{206a}\u{206b}\u{206c}\u{206d}\u{206e}\u{206f}fòô"], // Spaces U+2068 to U+206F
+            ['fòô', "\u{205f}fòô\u{205f}"], // Medium mathematical space (U+205F)
+            ['fòô', "\u{3000}fòô\u{3000}"], // Ideographic space (U+3000)
+            ['fòô', "\u{feff}fòô\u{feff}"], // Zero width no-break space (U+FEFF)
+        ];
+    }
+
 }
diff --git a/tests/codeception/common/unit/validators/EmailValidatorTest.php b/tests/codeception/common/unit/validators/EmailValidatorTest.php
index d6f4425..614085a 100644
--- a/tests/codeception/common/unit/validators/EmailValidatorTest.php
+++ b/tests/codeception/common/unit/validators/EmailValidatorTest.php
@@ -20,6 +20,16 @@ class EmailValidatorTest extends TestCase {
         $this->validator = new EmailValidator();
     }
 
+    public function testValidateTrimming() {
+        // Prevent it to access to db
+        Mock::func(YiiEmailValidator::class, 'checkdnsrr')->andReturn(false);
+
+        $model = $this->createModel("testemail@ely.by\u{feff}"); // Zero width no-break space (U+FEFF)
+        $this->validator->validateAttribute($model, 'field');
+        $this->assertEquals(['error.email_invalid'], $model->getErrors('field'));
+        $this->assertEquals('testemail@ely.by', $model->field);
+    }
+
     public function testValidateAttributeRequired() {
         $model = $this->createModel('');
         $this->validator->validateAttribute($model, 'field');
diff --git a/tests/codeception/common/unit/validators/UsernameValidatorTest.php b/tests/codeception/common/unit/validators/UsernameValidatorTest.php
index 34ed86e..58154a5 100644
--- a/tests/codeception/common/unit/validators/UsernameValidatorTest.php
+++ b/tests/codeception/common/unit/validators/UsernameValidatorTest.php
@@ -18,6 +18,13 @@ class UsernameValidatorTest extends TestCase {
         $this->validator = new UsernameValidator();
     }
 
+    public function testValidateTrimming() {
+        $model = $this->createModel("HereIsJohnny#\u{feff}"); // Zero width no-break space (U+FEFF)
+        $this->validator->validateAttribute($model, 'field');
+        $this->assertEquals(['error.username_invalid'], $model->getErrors('field'));
+        $this->assertEquals('HereIsJohnny#', $model->field);
+    }
+
     public function testValidateAttributeRequired() {
         $model = $this->createModel('');
         $this->validator->validateAttribute($model, 'field');