diff --git a/src/color.cpp b/src/color.cpp
index 098aa5cd7..19adc390f 100644
--- a/src/color.cpp
+++ b/src/color.cpp
@@ -188,7 +188,7 @@ wcstring_list_t rgb_color_t::named_color_names(void)
 {
     size_t count = sizeof named_colors / sizeof *named_colors;
     wcstring_list_t result;
-    result.reserve(count);
+    result.reserve(1 + count);
     for (size_t i=0; i < count; i++)
     {
         result.push_back(named_colors[i].name);