diff --git a/phpBB/styles/prosilver/template/captcha_recaptcha.html b/phpBB/styles/prosilver/template/captcha_recaptcha.html
index 97d2cda28e..51a1615bd5 100644
--- a/phpBB/styles/prosilver/template/captcha_recaptcha.html
+++ b/phpBB/styles/prosilver/template/captcha_recaptcha.html
@@ -16,6 +16,7 @@
 		// <![CDATA[
 		var RecaptchaOptions = {
 			lang : '{LA_RECAPTCHA_LANG}',
+			theme : 'clean',
 			tabindex : <!-- IF $CAPTCHA_TAB_INDEX -->{$CAPTCHA_TAB_INDEX}<!-- ELSE -->10<!-- ENDIF -->
 		};
 		// ]]>
diff --git a/phpBB/styles/subsilver2/template/captcha_recaptcha.html b/phpBB/styles/subsilver2/template/captcha_recaptcha.html
index 3776c77ea4..ec09b28ef5 100644
--- a/phpBB/styles/subsilver2/template/captcha_recaptcha.html
+++ b/phpBB/styles/subsilver2/template/captcha_recaptcha.html
@@ -9,6 +9,7 @@
 		// <![CDATA[
 		var RecaptchaOptions = {
 			lang : '{LA_RECAPTCHA_LANG}',
+			theme : 'clean',
 			tabindex : <!-- IF $CAPTCHA_TAB_INDEX -->{$CAPTCHA_TAB_INDEX}<!-- ELSE -->10<!-- ENDIF -->
 		};
 		// ]]>