diff --git a/app/javascript/dashboard/routes/dashboard/settings/inbox/components/AccountHealth.vue b/app/javascript/dashboard/routes/dashboard/settings/inbox/components/AccountHealth.vue
index 2eddb7f6b..a6ef33e5f 100644
--- a/app/javascript/dashboard/routes/dashboard/settings/inbox/components/AccountHealth.vue
+++ b/app/javascript/dashboard/routes/dashboard/settings/inbox/components/AccountHealth.vue
@@ -2,6 +2,7 @@
 import { computed } from 'vue';
 import { useI18n } from 'vue-i18n';
 import { copyTextToClipboard } from 'shared/helpers/clipboard';
+import { useLocale } from 'shared/composables/useLocale';
 
 import ButtonV4 from 'next/button/Button.vue';
 import Icon from 'dashboard/components-next/icon/Icon.vue';
@@ -28,7 +29,8 @@ const props = defineProps({
 
 const emit = defineEmits(['registerWebhook', 'goToConfiguration']);
 
-const { t, te, locale } = useI18n();
+const { t, te } = useI18n();
+const { resolvedLocale } = useLocale();
 
 const QUALITY_COLORS = {
   GREEN: 'text-n-teal-11',
@@ -77,7 +79,7 @@ const formatDateTime = value => {
   const date = new Date(value);
   if (Number.isNaN(date.getTime())) return value;
 
-  return new Intl.DateTimeFormat(locale.value, {
+  return new Intl.DateTimeFormat(resolvedLocale.value, {
     dateStyle: 'medium',
     timeStyle: 'short',
   }).format(date);
diff --git a/app/javascript/dashboard/routes/dashboard/settings/inbox/components/specs/AccountHealth.spec.js b/app/javascript/dashboard/routes/dashboard/settings/inbox/components/specs/AccountHealth.spec.js
index cca7bfbb5..ef45cb4a8 100644
--- a/app/javascript/dashboard/routes/dashboard/settings/inbox/components/specs/AccountHealth.spec.js
+++ b/app/javascript/dashboard/routes/dashboard/settings/inbox/components/specs/AccountHealth.spec.js
@@ -2,11 +2,13 @@ import { shallowMount } from '@vue/test-utils';
 import ButtonV4 from 'next/button/Button.vue';
 import AccountHealth from '../AccountHealth.vue';
 
+const { locale } = vi.hoisted(() => ({ locale: { value: 'en' } }));
+
 vi.mock('vue-i18n', () => ({
   useI18n: () => ({
     t: key => key,
     te: () => false,
-    locale: { value: 'en' },
+    locale,
   }),
 }));
 
@@ -17,6 +19,7 @@ describe('AccountHealth', () => {
     });
 
   beforeEach(() => {
+    locale.value = 'en';
     vi.spyOn(window, 'open').mockImplementation(() => {});
   });
 
@@ -67,6 +70,16 @@ describe('AccountHealth', () => {
     );
   });
 
+  it('formats dates for underscore-based locales', () => {
+    locale.value = 'pt_BR';
+
+    const wrapper = mountComponent({
+      last_onboarded_time: '2026-05-29T20:11:58+0000',
+    });
+
+    expect(wrapper.text()).toContain('2026');
+  });
+
   it('shows the current error instead of stale health data', () => {
     const wrapper = mountComponent(
       { verified_name: 'Stale Business Name' },