diff --git a/.changeset/gold-rooms-bake.md b/.changeset/gold-rooms-bake.md
new file mode 100644
index 00000000000..1bc2ffe73d6
--- /dev/null
+++ b/.changeset/gold-rooms-bake.md
@@ -0,0 +1,5 @@
+---
+'@primer/react': patch
+---
+
+Banner: stack inline actions vertically on narrow viewports.
diff --git a/.playwright/snapshots/components/Banner.test.ts-snapshots/Banner-ActionsInline-primer-breakpoint-xs-linux.png b/.playwright/snapshots/components/Banner.test.ts-snapshots/Banner-ActionsInline-primer-breakpoint-xs-linux.png
new file mode 100644
index 00000000000..4bcd5ea5876
Binary files /dev/null and b/.playwright/snapshots/components/Banner.test.ts-snapshots/Banner-ActionsInline-primer-breakpoint-xs-linux.png differ
diff --git a/e2e/components/Banner.test.ts b/e2e/components/Banner.test.ts
index 1ce4a1676d0..e5bfa8d35f8 100644
--- a/e2e/components/Banner.test.ts
+++ b/e2e/components/Banner.test.ts
@@ -73,6 +73,7 @@ const stories: Array<{title: string; id: string; viewports?: Array<keyof typeof
   {
     title: 'ActionsInline',
     id: 'components-banner-features--actions-layout-inline',
+    viewports: ['primer.breakpoint.xs'],
   },
   {
     title: 'ActionsStacked',
diff --git a/packages/react/src/Banner/Banner.module.css b/packages/react/src/Banner/Banner.module.css
index 07b04346567..06f944beaef 100644
--- a/packages/react/src/Banner/Banner.module.css
+++ b/packages/react/src/Banner/Banner.module.css
@@ -45,6 +45,20 @@
     & .BannerActions :where([data-primary-action='leading']) {
       display: none;
     }
+
+    @media screen and (--viewportRange-narrow) {
+      & .BannerContainer {
+        flex-direction: column;
+      }
+
+      & .BannerActions :where([data-primary-action='trailing']) {
+        display: none;
+      }
+
+      & .BannerActions :where([data-primary-action='leading']) {
+        display: flex;
+      }
+    }
   }
 
   &[data-layout='compact'] {