diff --git a/CHANGELOG.md b/CHANGELOG.md
index dc1e6f0..829503c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -38,7 +38,7 @@ added which have now been removed and those which GDS have removed over time.
 
 However, variables which have now been removed from our \_variables.scss are:
 
--   `$tbxforms-border-colour-conditional` (no longer configurable; now using GDS' `mid-grey` (#b1b4b6)) [#80]
+-   `$tbxforms-border-colour-conditional` (no longer configurable; now using GDS' `$tbxforms-border-colour`) [#80]
 -   `$tbxforms-border-width-conditional` (no longer configurable; now using GDS' `$tbxforms-border-width`) [#80]
 -   `$tbxforms-weight--bold` (use `$tbxforms-font-weight-bold` instead) [#80]
 -   `$tbxforms-weight--normal` (use `$tbxforms-font-weight-regular` instead) [#80]
diff --git a/tbxforms/static/sass/_conditional.scss b/tbxforms/static/sass/_conditional.scss
index 9d2fefd..7de0e47 100644
--- a/tbxforms/static/sass/_conditional.scss
+++ b/tbxforms/static/sass/_conditional.scss
@@ -3,6 +3,6 @@
 */
 
 .tbxforms-conditional {
-    border-left: $tbxforms-border-width solid tbxforms-colour('mid-grey');
+    border-left: $tbxforms-border-width solid $tbxforms-border-colour;
     padding-left: $tbxforms-gutter-half;
 }