diff --git a/.changeset/chilly-cloths-heal.md b/.changeset/chilly-cloths-heal.md
new file mode 100644
index 00000000000..0cfefdd502d
--- /dev/null
+++ b/.changeset/chilly-cloths-heal.md
@@ -0,0 +1,5 @@
+---
+'@primer/react': patch
+---
+
+ActionList: Fix trailing action button to take full height.
diff --git a/packages/react/src/ActionList/ActionList.module.css b/packages/react/src/ActionList/ActionList.module.css
index c5346c98bff..64feb5d8d88 100644
--- a/packages/react/src/ActionList/ActionList.module.css
+++ b/packages/react/src/ActionList/ActionList.module.css
@@ -588,6 +588,11 @@
 
 .TrailingAction {
   grid-area: trailingAction;
+
+  /* if child is loading button */
+  & > *[data-loading-wrapper] {
+    height: 100%;
+  }
 }
 
 /* wrapper span
@@ -689,6 +694,7 @@ span wrapping svg or text */
 .TrailingActionButton {
   border-top-left-radius: 0;
   border-bottom-left-radius: 0;
+  height: 100%;
 
   /* Preserve width consistency when loading state is active for text buttons only */
   &[data-loading='true']:has([data-component='buttonContent']) {