diff --git a/src/Forms/Form.php b/src/Forms/Form.php
index 96b9d1ee454..b31a10f6941 100644
--- a/src/Forms/Form.php
+++ b/src/Forms/Form.php
@@ -494,7 +494,8 @@ public function loadMessagesFrom($result)
                 $owner = $this;
             }
 
-            $owner->setMessage($message['message'], $message['messageType'], $message['messageCast']);
+            $owner->appendMessage($message['message'], $message['messageType'], $message['messageCast']);
+
         }
         return $this;
     }
diff --git a/src/Forms/FormMessage.php b/src/Forms/FormMessage.php
index 3fd5c56e242..756a31228af 100644
--- a/src/Forms/FormMessage.php
+++ b/src/Forms/FormMessage.php
@@ -31,7 +31,6 @@ trait FormMessage
      */
     protected $messageCast = null;
 
-
     /**
      * Returns the field message, used by form validation.
      *
@@ -92,6 +91,30 @@ public function setMessage(
         return $this;
     }
 
+    /**
+     * Appends a message to the existing message if the types match, overrides if not
+     */
+    public function appendMessage(
+        string $message,
+        string $messageType = ValidationResult::TYPE_ERROR,
+        string $messageCast = ValidationResult::CAST_TEXT,
+    ): static {
+        if (!empty($this->message)) {
+            $canBeMerged = ($messageType === $this->getMessageType() && $messageCast === $this->getMessageCast());
+            // Checks that the exact message string is not already contained before appending
+            if ($canBeMerged && strpos($this->message, $message) === false) {
+                $message = sprintf(
+                    '%s%s%s',
+                    $this->message,
+                    $messageType === ValidationResult::CAST_HTML ? '<br />' : PHP_EOL,
+                    $message
+                );
+            }
+        }
+
+        return $this->setMessage($message, $messageType, $messageCast);
+    }
+
     /**
      * Get casting helper for message cast, or null if not known
      *
diff --git a/tests/php/Forms/FormTest.php b/tests/php/Forms/FormTest.php
index eab888d68be..99351980136 100644
--- a/tests/php/Forms/FormTest.php
+++ b/tests/php/Forms/FormTest.php
@@ -1030,6 +1030,41 @@ public function testFieldMessageEscapeHtml()
         );
     }
 
+    public function testFieldMessageAppend()
+    {
+        $form = $this->getStubForm();
+        $form->appendMessage('Just a string');
+        $parser = new CSSContentParser($form->forTemplate());
+        $messageEls = $parser->getBySelector('#Form_Form_key1_Holder .message');
+        $this->assertStringContainsString('Just a string', $messageEls[0]->asXML());
+
+        $form->appendMessage('Certainly different');
+        $parser = new CSSContentParser($form->forTemplate());
+        $messageEls = $parser->getBySelector('#Form_Form_key1_Holder .message');
+        $this->assertStringContainsString('Just a string' . PHP_EOL . 'Certainly different', $messageEls[0]->asXML());
+
+        $form->appendMessage('Just a string');
+        $parser = new CSSContentParser($form->forTemplate());
+        $messageEls = $parser->getBySelector('#Form_Form_key1_Holder .message');
+        $this->assertStringContainsString('Just a string' . PHP_EOL . 'Certainly different', $messageEls[0]->asXML());
+        $this->assertEquals(1, substr_count($messageEls[0]->asXML(), 'Just a string'), 'Should not append if already present');
+
+        $form->appendMessage('This is a good message', ValidationResult::TYPE_GOOD);
+        $parser = new CSSContentParser($form->forTemplate());
+        $messageEls = $parser->getBySelector('#Form_Form_key1_Holder .message');
+        $this->assertStringContainsString('This is a good message', $messageEls[0]->asXML());
+        $this->assertStringNotContainsString('Just a string', $messageEls[0]->asXML());
+        $this->assertStringNotContainsString('Certainly different', $messageEls[0]->asXML());
+
+        $form->appendMessage('HTML is the future of the web', ValidationResult::TYPE_GOOD, ValidationResult::CAST_HTML);
+        $parser = new CSSContentParser($form->forTemplate());
+        $messageEls = $parser->getBySelector('#Form_Form_key1_Holder .message');
+        $this->assertStringContainsString('HTML is the future of the web', $messageEls[0]->asXML());
+        $this->assertStringNotContainsString('This is a good message', $messageEls[0]->asXML());
+        $this->assertStringNotContainsString('Just a string', $messageEls[0]->asXML());
+        $this->assertStringNotContainsString('Certainly different', $messageEls[0]->asXML());
+    }
+
     public function testGetExtraFields()
     {
         $form = new FormTest\ExtraFieldsForm(