diff --git a/include/internal/catch_stringref.h b/include/internal/catch_stringref.h
index 62d97658..0f9e7801 100644
--- a/include/internal/catch_stringref.h
+++ b/include/internal/catch_stringref.h
@@ -116,7 +116,7 @@ namespace Catch {
 
     auto operator << ( std::ostream& os, StringRef const& sr ) -> std::ostream&;
 
-    inline auto operator ""_sr( char const* rawChars, std::size_t size ) noexcept -> StringRef {
+    inline auto operator "" _sr( char const* rawChars, std::size_t size ) noexcept -> StringRef {
         return StringRef( rawChars, size );
     }