diff --git a/composer.json b/composer.json
index 5b5c98a..8fa18e8 100644
--- a/composer.json
+++ b/composer.json
@@ -21,7 +21,7 @@
         "silverstripe/framework": "^6"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.6",
+        "phpunit/phpunit": "^11.3",
         "silverstripe/versioned": "^3",
         "squizlabs/php_codesniffer": "^3",
         "silverstripe/userforms": "^7",
diff --git a/tests/EditableSpamProtectionFieldTest.php b/tests/EditableSpamProtectionFieldTest.php
index 182de53..55d3a8e 100644
--- a/tests/EditableSpamProtectionFieldTest.php
+++ b/tests/EditableSpamProtectionFieldTest.php
@@ -43,7 +43,7 @@ class EditableSpamProtectionFieldTest extends SapphireTest
             ->getFormField() // mock
             ->expects($this->once())
             ->method('validate')
-            ->will($this->returnValue(true));
+            ->willReturn(true);
 
         $formMock
             ->expects($this->never())
@@ -61,7 +61,7 @@ class EditableSpamProtectionFieldTest extends SapphireTest
             ->getFormField() // mock
             ->expects($this->once())
             ->method('validate')
-            ->will($this->returnValue(false));
+            ->willReturn(false);
 
         $formMock->getValidator()->validationError('MyField', 'some field message', 'required');
 
@@ -82,7 +82,7 @@ class EditableSpamProtectionFieldTest extends SapphireTest
             ->getFormField() // mock
             ->expects($this->once())
             ->method('validate')
-            ->will($this->returnValue(false));
+            ->willReturn(false);
 
         // field doesn't set any validation errors here
 
@@ -123,14 +123,14 @@ class EditableSpamProtectionFieldTest extends SapphireTest
     protected function getFormMock()
     {
         $formMock = $this->getMockBuilder(Form::class)
-            ->setMethods(['sessionMessage', 'sessionError', 'getValidator'])
+            ->onlyMethods(['sessionMessage', 'sessionError', 'getValidator'])
             ->disableOriginalConstructor()
             ->getMock();
 
         $formMock
             ->expects($this->any())
             ->method('getValidator')
-            ->will($this->returnValue(new RequiredFields()));
+            ->willReturn(new RequiredFields());
 
         return $formMock;
     }