diff --git a/src/govuk/components/_custom/header/_header.scss b/src/govuk/components/_custom/header/_header.scss
index 3166f28bd1..5e5c7310b8 100644
--- a/src/govuk/components/_custom/header/_header.scss
+++ b/src/govuk/components/_custom/header/_header.scss
@@ -152,7 +152,6 @@
       padding: 0;
       border: 0;
       border-radius: 3px;
-      opacity: .5;
       color: $sdn-search-button-color;
       background: $sdn-search-button-background $icon-search no-repeat center center;
       background-size: 18px 18px;